Performance information

• Spatially variable parametric sound image presentation with sparsely arranged ultrasonic sources with controlled emission direction　　　　　　　　　　　　　　　
  Takeru Momoki; Masaya Takasaki; Keisuke Hasegawa
  Applied Acoustics, Volume：231, First page：110547, Last page：110547, Mar. 2025, [Reviewed]
  Elsevier BV, Scientific journal
  DOI：https://doi.org/10.1016/j.apacoust.2025.110547
  DOI ID：10.1016/j.apacoust.2025.110547, ISSN：0003-682X
• Correction for restoring force in mass measurement using dead-zone relay feedback of displacement
  Takeshi MIZUNO; Reo TANAKA; Hironori KAI; Yuji ISHINO; Masaya TAKASAKI
  Mechanical Engineering Journal, Mar. 2025, [Reviewed]
  Japan Society of Mechanical Engineers, Scientific journal
  DOI：https://doi.org/10.1299/mej.24-00453
  DOI ID：10.1299/mej.24-00453, eISSN：2187-9745
• Introduction of DC magnetic suspension to AC magnetic suspension using magnetic resonant coupling
  Takuma KOBAYASHI; Takeshi MIZUNO; Masaya TAKASAKI; Yuji ISHINO
  Transactions of the JSME (in Japanese), Volume：90, Number：937, First page：24, Last page：00096, Sep. 2024, [Reviewed]
  Japan Society of Mechanical Engineers, Scientific journal
  DOI：https://doi.org/10.1299/transjsme.24-00096
  DOI ID：10.1299/transjsme.24-00096, eISSN：2187-9761
• Introduction of DC magnetic suspension to AC magnetic suspension using magnetic resonant coupling
  Takuma KOBAYASHI; Takeshi MIZUNO; Masaya TAKASAKI; Yuji ISHINO
  Transactions of the JSME (in Japanese), Volume：90, Number：937, First page：24, Last page：00096, Sep. 2024, [Reviewed]
  Japan Society of Mechanical Engineers, Scientific journal
  DOI：https://doi.org/10.1299/transjsme.24-00096
  DOI ID：10.1299/transjsme.24-00096, eISSN：2187-9761
• Effect of a Body Part Action on Body Perception of the Other Inactive Body Part
  Masayuki Hara; Hisato Sugata; Naofumi Otsuru; Masaya Takasaki; Yuji Ishino; Takeshi Mizuno; Masahito Miki; Noriaki Kanayama
  IEEE Transactions on Cognitive and Developmental Systems, First page：1, Last page：1, 2022
  Institute of Electrical and Electronics Engineers (IEEE), Scientific journal
  DOI：https://doi.org/10.1109/tcds.2022.3210659
  DOI ID：10.1109/tcds.2022.3210659, ISSN：2379-8920, eISSN：2379-8939
• Fabrication of a Polyimide Film Pneumatic Actuator by Molding and Welding Processes
  Daisuke Yamaguchi; Tatsuya Hanaki; Yuji Ishino; Masaya Takasaki; Takeshi Mizuno
  Actuators, Volume：10, Number：8, First page：177, Last page：177, Jul. 2021
  The bellows pneumatic actuator, which is made by folding a non-stretch film, has been proposed for various applications because it is easy to fabricate and is extremely thin and light. However, it has subpar durability performance, especially in the folded part of the film. In this study, we propose an actuator with a pod structure that possesses high design flexibility and is free from folding. A method of molding a pod structure on a polyimide film was established and a pneumatic actuator was successfully fabricated by using PI films. Two types of PI film pneumatic actuators with the same curvature, bellows type, and pod type were fabricated. Both were confirmed to have equivalent output characteristics. The bending angle and generated torque of the pod-structure actuator were 34° and 3.3 mNm, respectively. In addition, the pod structure has approximately twice the durability of the bellows structure. By using the fabrication method proposed in this paper, it is possible to realize an air chamber (i.e., an actuator) that has both high durability and bending motion.
  MDPI AG, Scientific journal
  DOI：https://doi.org/10.3390/act10080177
  DOI ID：10.3390/act10080177, eISSN：2076-0825
• Position-insensitive estimation of mass from limit cycle of velocity feedback relay system with Spring　　　　　　　　　　　　　　　
  Takeshi Mizuno; Taku Egawa; Masaya Takasaki; Yuji Ishino
  Measurement and Control (United Kingdom), 2021
  Mass measurement using relay feedback of velocity and restoring force compensation is investigated for determining the mass of an object under weightless conditions. In the measurement system, the velocity of the object is fed back through a relay with hysteresis and the force acting on the object is switched from a positive value to a negative value when the velocity reaches a positive threshold and vice versa. As a result, a limit cycle is induced in the measurement system and the mass is estimated based on the period of the limit cycle. In addition, restoring force compensation with a spring is introduced to avoid the drift of the trajectory. This compensation makes the static equilibrium state unique. However, the trajectory still drifts slightly. It causes some error in measurement when a simple formula of estimating mass is applied. To eliminate such an error, a new formula is derived to estimate the mass independently of the position of the trajectory that is determined by the switching positions in the relay actions. When the switching positions deflect from the origin at which the spring is in the natural length, the trajectory is not at the center and becomes asymmetric. It is analytically shown that the period of the limit cycle is minimum when the switching positions are at the origin. It indicates that mass is overestimated with the simple estimation formula when the trajectory is not at the center. The validity of the modified formula and the analytical results are confirmed experimentally.
  SAGE Publications Ltd, English, Scientific journal
  DOI：https://doi.org/10.1177/00202940211021874
  DOI ID：10.1177/00202940211021874, ISSN：0020-2940, SCOPUS ID：85107548210
• Concept and Prototype of Soft Actuator for Liquid Nitrogen Temperature Environments
  Daisuke Yamaguchi; Tatsuya Hanaki; Yuji Ishino; Masayuki Hara; Masaya Takasaki; Takeshi Mizuno
  Journal of Robotics and Mechatronics, Volume：32, Number：5, First page：1019, Last page：1026, Oct. 2020
  A prototype of a soft actuator for extreme environments was fabricated, and driven in a cryogenic temperature environment. Previous soft actuators cannot be used for robots in extreme environments because resin, the main fabrication material, exhibits weak environmental characteristics. Therefore, this study proposes the application of polyimide (PI) films to soft actuators. PI is characterized by excellent environmental resistance. However, the welding of PI is difficult because of its high resistance. In this study, a welding method was developed for PI films. This method does not require pretreatment, or the use of adhesives or additives to reduce resistance. Hence, an actuator that utilizes all the characteristics of PI was realized. The actuator was characterized in a cryogenic environment, which is one of the extreme environments, and was successfully driven at a liquid nitrogen temperature of 78 K. This proposed technology is not limited to cryogenic environments and is expected to provide extreme environmental resistance to existing soft robots.
  Fuji Technology Press Ltd., Scientific journal
  DOI：https://doi.org/10.20965/jrm.2020.p1019
  DOI ID：10.20965/jrm.2020.p1019, ISSN：0915-3942, eISSN：1883-8049
• An Equivalent Circuit Analysis and Suspension Characteristics of AC Magnetic Suspension Using Magnetic Resonant Coupling
  Arifur Rahman; Takeshi Mizuno; Masaya Takasaki; Yuji Ishino
  Actuators, Volume：9, Number：3, First page：52, Last page：52, Jul. 2020
  The fundamental characteristics and performances of alternating current (AC) magnetic suspension using magnetic resonant coupling are studied analytically and experimentally. Nowadays, wireless power transfer to the suspended object is required during non-contact suspension in some applications. Therefore, magnetic resonant coupling has been introduced for AC magnetic suspension to achieve self-stabilizing magnetic suspension and energy transfer to the floator simultaneously. The effect of circuit parameters for developing an experimental apparatus and performances are predicted from the solution of the equivalent circuits analytically. First, an equivalent magnetic circuit is derived and analyzed to characterize the self-inductance and mutual inductance with the gap. Second, an equivalent electrical circuit is analyzed to derive the current and force equations including magnetic parameters of the circuit. The derivation of these equations is numerically solved to study the characteristics of the primary current, the secondary current, and the force with respect to the gap and the applied frequency. The comparison between theoretical and experimental results is depicted, and the reason for differences is explained. The experimental and theoretical results show that positive stiffness is possible, which is essential for achieving self-stabilization. The self-stability is confirmed by the frequency response of the suspension system to disturbance experimentally.
  MDPI AG, Scientific journal
  DOI：https://doi.org/10.3390/act9030052
  DOI ID：10.3390/act9030052, eISSN：2076-0825
• Actuation Force Characteristics of Non-contact Ultrasonic Suspension Mechanism for Minute Object (2nd Report)
  Masaya TAKASAKI; Ryutaro CHIDA; Masahiro KUBOTA; Yuji ISHINO; Takeshi MIZUNO
  Journal of the Japan Society for Precision Engineering, Volume：86, Number：5, First page：341, Last page：346, May 2020
  Japan Society for Precision Engineering, Scientific journal
  DOI：https://doi.org/10.2493/jjspe.86.341
  DOI ID：10.2493/jjspe.86.341, ISSN：0912-0289, eISSN：1882-675X
• Development of three-degree-of-freedom zero-compliance mechanism for micro force measurement with a cantilever　　　　　　　　　　　　　　　
  Takeshi Mizuno; Yoichiro Hayashi; Masaya Takasaki; Yuji Ishino; Daisuke Yamaguchi
  IFAC-PapersOnLine, Volume：53, Number：2, First page：8339, Last page：8344, 2020
  A multi-degree-of-freedom zero-compliance mechanism is developed for measuring micro force with a cantilever. The force acting on a tip of the cantilever is usually estimated from the displacement of the tip caused by the force. However, the position and attitude of the tip vary after force acts on the tip from the original ones. To keep them invariant, a three-degree-of-freedom zero compliance mechanism is designed, fabricated and installed into a force measurement system. In the developed measurement system, the force is estimated from the displacement/attitude of a detection point of the zero-compliance mechanism. It is confirmed analytically and experimentally that both vertical displacement and attitude of the detection point are proportional to the force applied to the tip.
  Elsevier B.V., English, International conference proceedings
  DOI：https://doi.org/10.1016/j.ifacol.2020.12.1618
  DOI ID：10.1016/j.ifacol.2020.12.1618, ISSN：2405-8963, SCOPUS ID：85105112371
• Performance study on newly developed AC magnetic suspension system using magnetic resonance coupling　　　　　　　　　　　　　　　
  Arifur Rahman; Takeshi Mizuno; Yuji Ishino; Masaya Takasaki; Daisuke Yamaguchi
  International Journal of Applied Electromagnetics and Mechanics, Volume：64, Number：1-4, First page：779, Last page：787, 2020
  A newly developed AC magnetic suspension system is designed and fabricated to investigate the performances. A new concept of design is revealed for operating the apparatus differentially where the floator is kept at a constant position despite changing the parameters of the upper stator electromagnets. An extensive finite element analysis is conducted to estimate the basic characteristics of the system. A permanent magnet is incorporated in this system to reduce the required supply energy to the stator electromagnets. Magnetic suspension with a maximum gap of 2.0 mm without any control with the upper electromagnet in cumulative coupling mode and with a gap of 3.0 mm with indirect damping in the differentially operated mode is achieved. The indirect damping is achieved by applying PD control to the stator. The individual force, current and phase for variable frequency and gap between primary and secondary electromagnet are measured to examine the basic characteristics and performances.
  IOS Press BV, English, International conference proceedings
  DOI：https://doi.org/10.3233/JAE-209390
  DOI ID：10.3233/JAE-209390, ISSN：1383-5416, SCOPUS ID：85091510314
• Suspension Characteristics of Differentially Operated AC Magnetic Suspension System Using Magnetic Resonant Coupling
  Arifur RAHMAN; Takeshi MIZUNO; Yuji ISHINO; Masaya TAKASAKI; Daisuke YAMAGUCHI
  Journal of the Japan Society of Applied Electromagnetics and Mechanics, Volume：28, Number：2, First page：94, Last page：100, 2020
  Japan Society of Applied Electromagnetics and Mechanics, Scientific journal
  DOI：https://doi.org/10.14243/jsaem.28.94
  DOI ID：10.14243/jsaem.28.94, ISSN：0919-4452, eISSN：2187-9257
• Stabilization of magnetic suspension system by a reset element (Adjustment of vibration attenuation characteristic)
  Yuji ISHINO; Takeshi MIZUNO; Masaya TAKASAKI; Daisuke YAMAGUCHI
  Transactions of the JSME (in Japanese), Volume：86, Number：891, First page：20, Last page：00015, 2020
  Japan Society of Mechanical Engineers, Scientific journal
  DOI：https://doi.org/10.1299/transjsme.20-00015
  DOI ID：10.1299/transjsme.20-00015, eISSN：2187-9761
• Development of bilateral operation system for the assembly of magnetized components
  Ryu MONJIYAMA; Takeshi MIZUNO; Yuji ISHINO; Masaya TAKASAKI; Daisuke YAMAGUCHI
  Transactions of the JSME (in Japanese), Volume：86, Number：888, First page：20, Last page：00004, 2020
  Japan Society of Mechanical Engineers, Scientific journal
  DOI：https://doi.org/10.1299/transjsme.20-00004
  DOI ID：10.1299/transjsme.20-00004, eISSN：2187-9761
• Suppression of vibration induced by reciprocal motion of displacer in cryopump with an active dynamic vibration absorber　　　　　　　　　　　　　　　
  Takeshi Mizuno; Takahito Iida; Yuji Ishino; Masaya Takasaki; Daisuke Yamaguchi
  IFAC-PapersOnLine, Volume：52, Number：15, First page：531, Last page：536, Sep. 2019
  An active dynamic vibration absorber is introduced to a cyropump system achieving ultra-high vacuum and extremely low temperature environments for fine observation and high-accuracy measurement. In a cryopump, a so-called displacer moves reciprocally for alternative adiabatic expansion and exhaust of helium gas. Such a motion induces vibration in the vacuum chamber on which the pump is fixed. It may negatively affect observation and measurement performed in the chamber. To remove this vibration effectively, an active dynamic vibration absorber is designed, fabricated and installed in the system. Both empirical and model-based approaches are applied in reducing vibration at multiple specified frequencies. Finally, the vibration is almost eliminated at five specified frequencies.
  Elsevier B.V., English, International conference proceedings
  DOI：https://doi.org/10.1016/j.ifacol.2019.11.730
  DOI ID：10.1016/j.ifacol.2019.11.730, ISSN：2405-8963, SCOPUS ID：85077498373
• Three-dimensional control of an iron ball by flux-path control mechanisms located around magnetic source　　　　　　　　　　　　　　　
  Takeshi Mizuno; Naoki Ishibashi; Yuji Ishino; Daisuke Yamaguchi; Masaya Takasaki
  2019 12th International Symposium on Linear Drives for Industry Applications, LDIA 2019, Jul. 2019
  Three-dimensional control is achieved in a magnetic suspension system with three flux-path control mechanisms located around a permanent magnet (magnetic source). In the flux-control mechanism, a ferromagnetic control plate is placed beside the magnetic source. The attractive force acting on an iron ball (floator) can be varied by moving the control plate in the vertical direction. The suspension force has two components: vertical and lateral. Therefore, three-dimensional control of the floator can be achieved by moving three control plates individually. Such suspension is realized in the developed experimental apparatus.
  Institute of Electrical and Electronics Engineers Inc., English, International conference proceedings
  DOI：https://doi.org/10.1109/LDIA.2019.8770971
  DOI ID：10.1109/LDIA.2019.8770971, SCOPUS ID：85073886212
• Proposal of Mass Estimation Regardless of Switching Position in a Relay Feedback Mass Measurement System　　　　　　　　　　　　　　　
  Taku Egawa; Takeshi Mizuno; Masaya Takasaki; Yuji Ishino; Daisuke Yamaguchi
  2019 12th Asian Control Conference, ASCC 2019, First page：997, Last page：1000, Jun. 2019
  A mass measurement system using relay feedback of velocity was developed. In this system, the velocity of the object was fed back through a relay with a hysteresis. Although the efficacy of the proposed method has been already confirmed experimentally, it was subject to drift mainly because only the velocity was fed back. To prevent such drift, a spring element was added to produce restoring force. However, smaller drifts still occurred and the trajectory of the object fluctuated because the switching positions are not determined uniquely. In this paper, an estimation formula is derived, which can estimate the mass regardless of switching positions. The efficacy of the derived formula is confirmed experimentally.
  Institute of Electrical and Electronics Engineers Inc., English, International conference proceedings
  SCOPUS ID：85069916405
• Realization of Vibration Absorption at Multiple Frequencies on Vacuum Chamber with Cryopump　　　　　　　　　　　　　　　
  Takeshi Mizuno; Takahito Iida; Yuji Ishino; Masaya Takasaki; Daisuke Yamaguchi; Masayuki Hara
  2019 12th Asian Control Conference, ASCC 2019, First page：699, Last page：703, Jun. 2019
  A vibration isolation device with an active dynamic vibration absorber is developed to remove vibration induced by a cryopump. Cryopump is used to make high-vacuum and low-temperature environments for precise measurement. However, it induces vibrations with multiple frequencies, which may deteriorate measurement accuracy. This study focuses on removing low-frequency vibration because conventional vibration isolation devices for cryopump can hardly remove such vibration. In the developed vibration isolation device, an active vibration absorber is used to remove the vibration efficiently at low frequencies. In this report, the design concept and structure of the fabricated apparatus are described.
  Institute of Electrical and Electronics Engineers Inc., English, International conference proceedings
  SCOPUS ID：85069913777
• Stabilization of Magnetic Suspension System by using First-Order-Reset Element without Derivative Feedback　　　　　　　　　　　　　　　
  Yuji Ishino; Takeshi Mizuno; Masaya Takasaki; Daisuke Yamaguchi
  2019 12th Asian Control Conference, ASCC 2019, First page：690, Last page：694, Jun. 2019
  The stabilization of a magnetic suspension system is achieved by using only a nonlinear integrator without other element. The proportional-derivative (PD) feedback is the simplest control method for the magnetic suspension system. The proportional element gives restoring force, and the derivative element gives damping to the system. However, the derivative feedback element needs to be carefully designed because unnecessary high-frequency signals generate an adverse effect. Meanwhile, installing a first-order-reset element (FORE) has been proposed to reduce the vibration. The element is a first-order low-pass filter (LPF) with reset functions. This paper proposes to stabilize a magnetic suspension system with a FORE only. However, the magnetic suspension system cannot be stabilized by the basic FORE. Therefore, the FORE is modified as to the reset conditions. A magnetic suspension system is stabilized by the modified FORE. The characteristics of the stabilized magnetic suspension system are studied experimentally.
  Institute of Electrical and Electronics Engineers Inc., English, International conference proceedings
  SCOPUS ID：85069900213
• Intermediate Control for Stable Trajectory in a Relay-Feedback Mass Measurement System　　　　　　　　　　　　　　　
  Takeshi Mizuno; Keisuke Nishizawa; Yuji Ishino; Masaya Takasaki; Daisuke Yamaguchi
  2019 12th Asian Control Conference, ASCC 2019, First page：685, Last page：689, Jun. 2019
  An intermediate control is introduced to mass measurement system using relay feedback of velocity to stabilize the trajectory. In the original system, the velocity of the object was fed back through a relay with hysteresis, and the mass of the object was determined by measuring the period of an induced limit cycle. It could determine the mass of the object rather accurately. However, the trajectory of the object easily drifted because only the velocity was fed back and there was no restoring force. To generate restoring force, a spring element was added. Although the drift became smaller, it still occurred. It caused the trajectory of the object to fluctuate. To eliminate such fluctuation, an intermediate control is introduced to stabilize the trajectory. The operation of the intermediate control is analyzed to prove the convergence of the trajectory.
  Institute of Electrical and Electronics Engineers Inc., English, International conference proceedings
  SCOPUS ID：85069893373
• Vibration control of cryopump with an active dynamic vibration absorber　　　　　　　　　　　　　　　
  T. Mizuno; T. IIda; Y. Ishino; M. Takasaki; M. Hara; D. Yamaguchi; T. Kano
  Transactions of the JSME, Volume：85, Number：873, First page：18-00461, May 2019, [Reviewed]
  Japanese, Scientific journal
  DOI：https://doi.org/10.1299/transjsme.18-00461
  DOI ID：10.1299/transjsme.18-00461
• Stabilization of Magnetic Suspension System by Using Only a First-Order Reset Element without a Derivative Element　　　　　　　　　　　　　　　
  Ishino Yuji; Mizuno Takeshi; Takasaki Masaya; Yamaguchi Daisuke
  ACTUATORS, Volume：8, Number：1, Mar. 2019, [Reviewed]
  DOI：https://doi.org/10.3390/act8010024
  DOI ID：10.3390/act8010024, ISSN：2076-0825, Web of Science ID：WOS:000464060100001
• Modeling and Validation of Vertical Direction Force Estimation with a Three-Dimensional Force Measurement Instrument Based on a Zero-Compliance Mechanism　　　　　　　　　　　　　　　
  Nahiyan Md; Helal An; Mizuno Takeshi; Takasaki Masaya; Ishino Yuji; Hara Masayuki; Yamaguchi Daisuke
  SENSORS, Volume：19, Number：4, Feb. 2019, [Reviewed]
  DOI：https://doi.org/10.3390/s19040799
  DOI ID：10.3390/s19040799, ISSN：1424-8220, PubMed ID：30781419, Web of Science ID：WOS:000460829200050
• Design and control of active vibration isolation system with an active dynamic vibration absorber operating as accelerometer　　　　　　　　　　　　　　　
  Rasid Syed Mamun R; Mizuno Takeshi; Ishino Yuji; Takasaki Masaya; Hara Masayuki; Yamaguchi Daisuke
  JOURNAL OF SOUND AND VIBRATION, Volume：438, First page：175, Last page：190, Jan. 2019, [Reviewed]
  DOI：https://doi.org/10.1016/j.jsv.2018.09.037
  DOI ID：10.1016/j.jsv.2018.09.037, ISSN：0022-460X, Web of Science ID：WOS:000447906200011
• Realization of Stable Trajectory in Mass Measurement System Using Relay Feedback of Velocity and Restoring Force Compensation　　　　　　　　　　　　　　　
  MIZUNO Takeshi; NISHIZAWA Keisuke; TAKASAKI Masaya; ISHINO Yuji; HARA Masayuki; YAMAGUCHI Daisuke
  SICE Journal of Control, Measurement, and System Integration, Volume：12, Number：3, First page：68, Last page：75, 2019, [Reviewed]
  <p>A mass measurement system using relay feedback of velocity was developed. In this system, the velocity of the object was fed back through a relay with hysteresis. Although the efficacy of the proposed method has been already confirmed experimentally, it was subject to a drift mainly because only the velocity was fed back. To prevent such a drift, a spring element was added to produce restoring force. However, smaller drifts still occurred, and the trajectory of the object fluctuated. To eliminate such fluctuations, intermediate control is introduced. It succeeds to eliminate fluctuation of the trajectory in the developed apparatus.</p>
  公益社団法人 計測自動制御学会, English
  ISSN：1882-4889, CiNii Articles ID：130007650240
• Development of a three‐degree‐of‐freedom control magnetic suspension system using laterally control flux‐path mechanisms　　　　　　　　　　　　　　　
  石橋尚宜; 水野毅; 石野裕二; 高崎正也; 山口大介
  日本機械学会論文集(Web), Volume：85, Number：869, First page：ROMBUNNO.18‐00228(J‐STAGE), Last page：00228-18-00228, 2019, [Reviewed]
  <p>A magnetic suspension system with three flux-path control mechanisms are developed to achieve three-dimensional positioning of the suspended object (floator). In the flux-control mechanism, a ferromagnetic control plate is located in the lateral direction of the magnetic source (permanent magnet). It was shown that the attractive force acting on the floator could be varied by moving the control plate in the vertical direction. In addition, the lateral force was generated by using two control plates located on both sides of the floator and moving them differentially. In this work, an apparatus is fabricated which has three flux-path control mechanisms. The configurations of the apparatus are described. Stable suspension is achieved and basic characteristics are studied. In addition, 3-degree-of-freedom (3-DOF) control suspension is achieved by moving three control plates individually. The 3-DOF control is evaluated by moving the floator in circular orbits.</p>
  一般社団法人 日本機械学会, Japanese
  ISSN：2187-9761, J-Global ID：201902255505816691, CiNii Articles ID：130007557540
• Active system with zero-compliance and zero-power characteristics
  Mhia Md. Zaglul Shahadat; Takeshi Mizuno; Yuji Ishino; Masaya Takasaki
  International Journal of Dynamics and Control, Volume：6, Number：4, First page：1617, Last page：1628, Dec. 2018
  Springer Science and Business Media LLC, Scientific journal
  DOI：https://doi.org/10.1007/s40435-018-0400-8
  DOI ID：10.1007/s40435-018-0400-8, ISSN：2195-268X, eISSN：2195-2698
• Vibration Suppression in the Passively-Supported Direction by Varying Bias Currents in Magnetic Suspension System　　　　　　　　　　　　　　　
  Takeshi Mizuno; Asief Javed; Yuji Ishino; Daisuke Yamaguchi; Masaya Takasaki
  2018 European Control Conference, ECC 2018, First page：971, Last page：976, Nov. 2018
  Vibration in the passively-supported direction is reduced by varying the stiffness in the suspension. The magnetic suspension system using the attractive force of an electromagnet is inherently unstable in the normal direction
  active control is necessary to achieve stable suspension. In contrast, it is usually stable in the lateral direction because of the edge effects in the magnetic circuits. However, damping in this direction is quite small so that vibration is easily induced. In this work, varying stiffness controls are applied to suppress the vibration. An experimental apparatus was built to examine the efficacy of the varying stiffness control. It has two electromagnets operated differentially. To adjust the stiffness in the passively-supported direction, the bias current of each electromagnet is varied simultaneously. First, the bias current is varied stepwise. The effect of the amplitude of step on vibration suppression is examined. Then, the bias current is varied continuously to avoid erroneous operations caused by noise included in the sensor signal. The efficacy of approximating the sign function by a continuous function is demonstrated experimentally.
  Institute of Electrical and Electronics Engineers Inc., English, International conference proceedings
  DOI：https://doi.org/10.23919/ECC.2018.8550236
  DOI ID：10.23919/ECC.2018.8550236, SCOPUS ID：85059824540
• Lateral Vibration Suppression by Varying Stiffness Control in a Vertically Active Magnetic Suspension System　　　　　　　　　　　　　　　
  Javed Asief; Mizuno Takeshi; Takasaki Masaya; Ishino Yuji; Hara Masayuki; Yamaguchi Daisuke
  ACTUATORS, Volume：7, Number：2, Jun. 2018, [Reviewed]
  DOI：https://doi.org/10.3390/act7020021
  DOI ID：10.3390/act7020021, ISSN：2076-0825, Web of Science ID：WOS:000436483900010
• Development of 3-DOF active controlled magnetic suspension system with common magnetic pole (1st Report: Fabrication of experimental apparatus)　　　　　　　　　　　　　　　
  Y. Ishino; T. Mizuno; M. Takasaki; M. Hara; D. Yamaguchi
  Journal of the Japan Society of Applied Electromagnetics and Mechanics, Volume：26, Number：1, First page：178, Last page：184, May 2018, [Reviewed]
  Japanese, Scientific journal
  DOI：https://doi.org/10.14243/jsaem.26.178
  DOI ID：10.14243/jsaem.26.178
• Basic characteristics of a parallel magnetic suspension system controlling two-degree-of-freedom motions　　　　　　　　　　　　　　　
  Y. Narisawa; T. Mizuno; M. Takasaki; Y. Ishino; M. Hara; D. Yamaguchi
  Transactions of the JSME, Volume：84, Number：861, First page：17-00523, May 2018, [Reviewed]
  Japanese, Scientific journal
  DOI：https://doi.org/10.1299/transjsme.17-00523
  DOI ID：10.1299/transjsme.17-00523
• Proposal of magnetic suspension with elastic ferromagnetic substance for vibration isolation system　　　　　　　　　　　　　　　
  Takeshi Mizuno; Megumi Namai; Masaya Takasaki; Yuji Ishino
  2017 International Automatic Control Conference, CACS 2017, Volume：2017-, First page：1, Last page：6, Feb. 2018
  An improvement of magnet suspension by using elastic ferromagnetic substance is proposed. The zero-power magnetic suspension has been applied to vibration isolation system because it has a negative-stiffness property. High stiffness against direct disturbance on the isolation table can be achieved by combining it with a normal spring with a positive stiffness. It enables the system to have good characteristics in both the performances of isolation from ground and suppression of direct vibration. However, the vibration isolation system using zero-power magnetic suspension has several problems. One of them is that a large/strong permanent magnet is necessary to support the isolation table. Another problem is a technical difficulty of achieving sufficient damping for suppressing resonance. It is proposed to insert elastic ferromagnetic substance between the magnet for suspension and the object to be suspended. Since it decreases magnetic reluctance, the suspension force increase. In addition, the damping characteristics of the suspension system is improved by the elasticity of the substance.
  Institute of Electrical and Electronics Engineers Inc., English, International conference proceedings
  DOI：https://doi.org/10.1109/CACS.2017.8284257
  DOI ID：10.1109/CACS.2017.8284257, SCOPUS ID：85050458629
• Realization of zero-power control in a two-degree-of-freedom double parallel magnetic suspension system　　　　　　　　　　　　　　　
  Y. Narisawa; T. Mizuno; M. Takasaki; Y. Ishino; M. Hara; D. Yamaguchi
  2017 Asian Control Conference, ASCC 2017, Volume：2018-, First page：1140, Last page：1145, Feb. 2018, [Reviewed]
  A basic single-degree-of-freedom magnetic suspension system consists of one floator, one electromagnet and one amplifier. For multi-degree-of-freedom control, multiple electromagnets and multiple amplifiers are necessary, which increases the cost of total system. As a means of overcoming this problem, parallel magnetic suspension has been proposed which controls multiple floators or multi-degree-of-freedom motions with a single power amplifier. This paper focuses on the zero-power control in a two-degree-of-freedom double parallel magnetic suspension system. The steady-state characteristics of this system are clarified by theoretical analysis. When the disturbance acts on one of the suspended points, a steady displacement appears only in the corresponding suspended point. The direction of the steady displacement is opposite to the direction of the disturbance. In addition, the direction of the transient response depends on the point that the disturbance acts on. In experimental apparatus, step response and frequency response are measured to verify the predictions.
  Institute of Electrical and Electronics Engineers Inc., English, International conference proceedings
  DOI：https://doi.org/10.1109/ASCC.2017.8287331
  DOI ID：10.1109/ASCC.2017.8287331, SCOPUS ID：85047528016
• Resonance frequency tracking control of ultrasonic transducer for diminished haptics　　　　　　　　　　　　　　　
  Masaya Takasaki; Daisuke Yamaguchi; Masayuki Hara; Yuji Ishino; Takeshi Mizuno
  2017 Asian Control Conference, ASCC 2017, Volume：2018-, First page：1240, Last page：1245, Feb. 2018, [Reviewed]
  Previously, 'diminished haptics' in which real surface texture can be transformed was proposed. Strong intensity ultrasonic vibration was applied to realize demonstration of the concept. To enjoy the demonstration, the intensity of the ultrasonic vibration on solid surface should be maintained. The ultrasonic transducer fabricated for this purpose consisted of a Langevin type ultrasonic transducer and a horn whose end was shaped in square. Large vibration amplitude can be acquired at resonance of the whole transducer as longitudinal vibration mode. On the other hand, resonant frequency easily changes due to operating conditions. To keep the amplitude, the resonant frequency should be tracked by real time. Tracking control with phase detection was applied with a newly developed control system. Step responses of oscillating frequency as results of tracking control are reported. The results show successful tracking control.
  Institute of Electrical and Electronics Engineers Inc., English, International conference proceedings
  DOI：https://doi.org/10.1109/ASCC.2017.8287348
  DOI ID：10.1109/ASCC.2017.8287348, SCOPUS ID：85047518976
• Application of phase-locked loop to mass measurement using damped dynamic vibration absorber　　　　　　　　　　　　　　　
  Takeshi Mizuno; Masaya Takasaki; Yuji Ishino
  2017 Asian Control Conference, ASCC 2017, Volume：2018-, First page：1134, Last page：1139, Feb. 2018, [Reviewed]
  Phase-locked loop (PLL) is applied to mass measurement using damped dynamic vibration absorber. The frequency response curves of a mass-spring system with a dynamic vibration absorber pass through a point that is independent of damping in the absorber. The measurement system utilizes this fixed point to estimate mass independently from damping. To carry out such measurement, the excitation frequency must be tuned to equal the frequency of the fixed point. For such tuning, PLL is applied. The PLL system consists of two detection circuits, a microcomputer and a direct digital synthesizer. It adjusts the excitation frequency for the phase between the excitation signal and the displacement of the absorber mass to be 180 degrees. In the experiments, the frequency responses are measured to confirm the existence of the fixed point. The automatic tuning is achieved by the developed system. Mass measurements are carried out in the developed apparatus. The results demonstrate the efficacy of the measurement using PLL and that the measurement utilizing the fixed point is insensitive to the damping in the absorber.
  Institute of Electrical and Electronics Engineers Inc., English, International conference proceedings
  DOI：https://doi.org/10.1109/ASCC.2017.8287330
  DOI ID：10.1109/ASCC.2017.8287330, SCOPUS ID：85047542058
• Force Measurement Using Zero-Compliance Mechanism　　　　　　　　　　　　　　　
  MIZUNO Takeshi; ISHINO Yuji; KAWADA Hiroki; HAYASHI Yoichiro; TAKASAKI Masaya; HARA Masayuki; YAMAGUCHI Daisuke
  SICE Journal of Control, Measurement, and System Integration, Volume：11, Number：4, First page：341, Last page：348, 2018, [Reviewed]
  <p>Force measurement using zero-compliance mechanism is proposed and studied experimentally. A zero-compliance mechanism is composed of two suspensions connected in series; one of them is operated to cancel the deflection of the other so that the total length of the suspension is maintained even if force acts between the ends. In the proposed measurement system, one of the ends becomes the point of force and the point of the connection becomes the detection point. The force is estimated from the displacement of the detection point. An apparatus is fabricated for experimental study to show the validity of the proposed measurement method. Double series magnetic suspension is used to achieve zero compliance. In the apparatus, the motions of two suspended objects (floators) are controlled with a single electromagnet. Each floator is supported by leaf springs to move in the vertical direction translationally. The attractive force of the electromagnet directly acts on the first floator in which a permanent magnet is installed. The motion of the second floator is controlled indirectly through the attractive force of the permanent magnet. To achieve the zero compliance characteristic, PID control is applied to the second floator. It is confirmed experimentally that the deflection of the second suspension, i.e., the distance between the first and second floators, is proportional to external force acting on the second floator. This result indicates that the force can be estimated for the deflection of the second suspension. It is also demonstrated that dynamic force can be measured by the proposed method.</p>
  公益社団法人 計測自動制御学会, English
  ISSN：1882-4889, CiNii Articles ID：130007427497
• Validation of multi-dimensional force measurement using zero-compliance mechanism　　　　　　　　　　　　　　　
  Nahiyan Md; Helal An; Mizuno Takeshi; Takasaki Masaya; Ishino Yuji; Hara Masayuki; Yamaguchi Daisuke
  JOURNAL OF ADVANCED MECHANICAL DESIGN SYSTEMS AND MANUFACTURING, Volume：12, Number：2, 2018, [Reviewed]
  DOI：https://doi.org/10.1299/jamdsm.2018jamdsm0038
  DOI ID：10.1299/jamdsm.2018jamdsm0038, ISSN：1881-3054, Web of Science ID：WOS:000435134000004
• Development of Three-Dimensional Force Measurement Instrument Using Zero-Compliance Mechanism　　　　　　　　　　　　　　　
  Md Helal An NAHIYAN; MIZUNO Takeshi; TAKASAKI Masaya; ISHINO Yuji; HARA Masayuki; YAMAGUCHI Daisuke
  Journal of the Japan Society of Applied Electromagnetics and Mechanics, Volume：26, Number：1, First page：172, Last page：177, 2018, [Reviewed]
  <p> A three-dimensional force measurement instrument is designed and developed by considering the basic principle of zero compliance mechanism. In the proposed system, the point of force and the detection point are connected in series and suspended with leaf springs. One of the suspensions operates to cancel the displacement of the other. If any force is applied at point of force that causes displacement, the detection point displaces proportionally to cancel out the displacement of the point of force. As a result, zero compliance is achieved at the point of force and applied force can be measured from the displacement of the detection point. This paper presents the design and construction of a three-dimensional force measurement instrument and the effectiveness of the proposed system is demonstrated by the experimental result of the vertical-direction force measurement.</p>
  日本AEM学会, English
  ISSN：0919-4452, CiNii Articles ID：130007378314
• Zero-power control of flux-path control magnetic suspension system with flux-interrupting plates　　　　　　　　　　　　　　　
  T. Mizuno; M. Takasaki; M. Hara; D. Yamaguchi; Y. Ishino
  LDIA 2017 - 11th International Symposium on Linear Drives for Industry Applications, Nov. 2017, [Reviewed]
  The feasibility of zero-power control in flux-path control magnetic suspension is discussed. In the flux-path control magnetic suspension system, ferromagnetic control plates are inserted between a permanent magnet (magnetic source) and a floator and moved to vary the flux from the magnetic source to the floator. The zero-power control has been applied in active magnetic suspension with a DC electromagnet. In the zero-power controlled system, the control current was kept virtually zero in the steady states. The applicability of the zero-power control to the flux-path control magnetic suspension is discussed in this paper. The conditions required to achieve the zero-power control is presented in an analytical form. Experiments are carried in a fabricated apparatus to certify the theoretical predictions.
  Institute of Electrical and Electronics Engineers Inc., English, International conference proceedings
  DOI：https://doi.org/10.23919/LDIA.2017.8097235
  DOI ID：10.23919/LDIA.2017.8097235, SCOPUS ID：85040639446
• Development of a Compact Axial Active Magnetic Bearing with a Function of Two-Tilt-Motion Control　　　　　　　　　　　　　　　
  Ishino Yuji; Mizuno Takeshi; Takasaki Masaya; Hara Masayuki; Yamaguchi Daisuke
  ACTUATORS, Volume：6, Number：2, Jun. 2017, [Reviewed]
  DOI：https://doi.org/10.3390/act6020014
  DOI ID：10.3390/act6020014, ISSN：2076-0825, Web of Science ID：WOS:000404562200003
• Realization of two-degree-of-freedom motions control using parallel magnetic suspension　　　　　　　　　　　　　　　
  Y. Narisawa; T. Mizuno; M. Takasaki; M. Hara; D. Yamaguchi; Y. Ishino
  Transactions of the JSME, Volume：83, Number：848, First page：16-00512, Apr. 2017, [Reviewed]
  Japanese, Scientific journal
  DOI：https://doi.org/10.1299/transjsme.16-00512
  DOI ID：10.1299/transjsme.16-00512
• The Proposal of Magnetic Suspension Using Laterally Control Flux-Path Mechanism　　　　　　　　　　　　　　　
  Ishibashi Naoki; Mizuno Takeshi; Ishino Yuji; Yamaguchi Daisuke; Hara Masayuki; Takasaki Masaya; Yamada Kazuki
  ACTUATORS, Volume：6, Number：1, Mar. 2017, [Reviewed]
  DOI：https://doi.org/10.3390/act6010011
  DOI ID：10.3390/act6010011, ISSN：2076-0825, Web of Science ID：WOS:000398700400010
• Method to Improve Welding of Polyimide Film for Pneumatic Film Actuator　　　　　　　　　　　　　　　
  Takai Kazuki; Yamaguchi Daisuke; Kamimura Ryotaro; Hanaki Tatsuya; Ishino Yuji; Hara Masayuki; Takasaki Masaya; Mizuno Takeshi
  Proceedings of JSPE Semestrial Meeting, Volume：2017, First page：173, Last page：174, 2017
  本研究ではこれまでに，ポリイミドフィルムを用いた空圧アクチュエータの試作を行ってきた．その中で，ポリイミドフィルム同士の溶着強度が弱いため，アクチュエータに印加可能な圧力が低いことが課題であった．本発表ではポリイミドフィルムアクチュエータへの印加圧力の向上を目的として，溶着手法の改善を行い，バルーン型アクチュエータに印加可能な最大圧力を評価した．
  The Japan Society for Precision Engineering, Japanese
  DOI：https://doi.org/10.11522/pscjspe.2017S.0_173
  DOI ID：10.11522/pscjspe.2017S.0_173, CiNii Articles ID：130006043669
• Development of Vibration Absorber Unit for Refrigerator of Cryopump 2nd report: Design of Vibration Control System　　　　　　　　　　　　　　　
  Iida Takahito; Mizuno Takeshi; Ishino Yuji; Takasaki Masaya; Hara Masayuki; Yamaguchi Daisuke
  Proceedings of the Japan Joint Automatic Control Conference, Volume：60, First page：1636, Last page：1639, 2017
  The Japan Joint Automatic Control Conference, Japanese
  DOI：https://doi.org/10.11511/jacc.60.0_1636
  DOI ID：10.11511/jacc.60.0_1636, CiNii Articles ID：130006251282
• Proposal of a pneumatic film actuator for liquid nitrogen temperature fabricated by molding process　　　　　　　　　　　　　　　
  YAMAGUCHI Daisuke; HANAKI Tatsuya; TAKAI Kazuki; ISHINO Yuji; HARA Masayuki; TAKASAKI Masaya; MIZUNO Takeshi
  The Proceedings of JSME annual Conference on Robotics and Mechatronics (Robomec), Volume：2017, First page：2A2, Last page：A06, 2017
  

  In this paper, we explained a pneumatic film actuator fabricated by molding process. In our previous research, a bending type actuator have been developed. The bending motion is occurred by pleated structure. The structure is formed by folding process of films. The folding process is performed manually and is complicated. Additionally, the pleated structure tends to be broken by repetitive driving. In this study, a molding process was developed for fabricating a structure that causes bending motion. By pressing a mold against polyimide film, the bending structure is formed. Fabricated actuators are evaluated at room temperature. The molding type actuator has the same performance as precious one.

  
  The Japan Society of Mechanical Engineers, Japanese
  DOI：https://doi.org/10.1299/jsmermd.2017.2A2-A06
  DOI ID：10.1299/jsmermd.2017.2A2-A06, CiNii Articles ID：130006220874
• Separation of Various Small Particles in a Laterally-Oscillated Rectangular Container　　　　　　　　　　　　　　　
  HARA Masayuki; NABAE Hiroyuki; YAMAGUCHI Daisuke; ISHINO Yuji; TAKASAKI Masaya; MIZUNO Takeshi
  The Proceedings of JSME annual Conference on Robotics and Mechatronics (Robomec), Volume：2017, First page：1A1, Last page：J09, 2017
  

  Our previous studies discovered that small particles scattered at the bottom of a water-filled rectangular container align at specific positions when the container is laterally oscillated at specific frequencies. Also, a batch manipulation method of submillimeter-scale small particles was proposed by using this unique phenomenon. In the present study, we attempt to develop a method to separate small particles with various sizes by using the lateral oscillation of a rectangular container. This paper considers lateral fluid velocity distribution in the rectangular container to reveal how the distribution affects the behavior of the small particles, and examines the possibility that the small particles with various sizes can have different behaviors.

  
  The Japan Society of Mechanical Engineers, Japanese
  DOI：https://doi.org/10.1299/jsmermd.2017.1A1-J09
  DOI ID：10.1299/jsmermd.2017.1A1-J09, CiNii Articles ID：130006220365
• Development of tactile display for investigation of higher frequency vibration perception discrimination　　　　　　　　　　　　　　　
  Sato Fumiki; Takasaki Masaya; Ishino Yuji; Yamaguchi Daisuke; Hara Masayuki; Mizuno Takeshi
  Proceedings of JSPE Semestrial Meeting, Volume：2017, First page：147, Last page：148, 2017
  人は物体表面をなぞった時，皮膚の振動を知覚することで物体の粗さを感じると考えられている．その粗さ感覚を提示する装置として多くのデバイスが開発されている．しかし，500Hz以上の人の振動知覚閾値は調べられておらず，その周波数以上の振動は考慮されていないことが多い．そのため，粗さの感覚を再現するのに適切な周波数帯域は分かっていない．そこで，500 Hz以上で人の振動知覚閾値が測定可能な実験装置を開発した．
  The Japan Society for Precision Engineering, Japanese
  DOI：https://doi.org/10.11522/pscjspe.2017S.0_147
  DOI ID：10.11522/pscjspe.2017S.0_147, CiNii Articles ID：130006043678
• Development of Pump Using Ultrasonic Transducer and Opposing Surface (5th Report)　　　　　　　　　　　　　　　
  Shinada Hiroaki; Takasaki Masaya; Ishino Yuji; Yamaguchi Daisuke; Hara Masayuki; Mizuno Takeshi
  Proceedings of JSPE Semestrial Meeting, Volume：2017, First page：149, Last page：150, 2017
  これまでに，内部配管を備えた超音波振動子にテーパ加工を施した面を対向させることで，ポンプ効果が発現することが確認されている．このポンプではスクイーズ膜効果を由来とした正圧により二面間にギャップが生じる．このギャップ内の圧力を対向子にはたらく反力として計測するために，対向子背後にロードセルを備えた．またボイルの法則を適用することで，取得したギャップ及び振幅から圧力を算出し実験値と比較した．
  The Japan Society for Precision Engineering, Japanese
  DOI：https://doi.org/10.11522/pscjspe.2017S.0_149
  DOI ID：10.11522/pscjspe.2017S.0_149, CiNii Articles ID：130006043680
• Wider-Gap Flux-Path Control Suspension System 3rd report: Design of Flux-Path Control Mechanism　　　　　　　　　　　　　　　
  Ishibashi Naoki; Mizuno Takeshi; Ishino YUji; Takasaki Masaya; Hara Masayuki; Yamaguchi Daisuke
  Proceedings of the Japan Joint Automatic Control Conference, Volume：60, First page：1658, Last page：1659, 2017
  The Japan Joint Automatic Control Conference, Japanese
  DOI：https://doi.org/10.11511/jacc.60.0_1658
  DOI ID：10.11511/jacc.60.0_1658, CiNii Articles ID：130006251320
• Higher frequency vibrations on surface acoustic wave tactile display　　　　　　　　　　　　　　　
  TAKASAKI Masaya; SATO Fumiki; HARA Masayuki; YAMAGUCHI Daisuke; ISHINO Yuji; MIZUNO Takeshi
  The Proceedings of JSME annual Conference on Robotics and Mechatronics (Robomec), Volume：2017, First page：1P1, Last page：M04, 2017
  

  Previously, a tactile display using surface acoustic wave which is a kind of ultrasonic vibration has been developed and can render tactile sensation like roughness. Basic principle is friction reduction induced by the wave and its control. Switching the wave at certain intervals results in vibrations on user's finger surface. To consider realistic rendering, frequency range of the vibration to be presented on the display will be discussed. Aim of this research is to investigate vibration presentation with frequency more than 500 Hz. Amplitude modulation of excited ultrasonic wave was confirmed as frequency response of amplitude modulation. The modulation like 10 kHz was observed. Output vibration as tactile display was also observed with an experimental setup. Mechanical vibration up to 10 kHz was acquired, successfully. Frequency characteristics were also observed.

  
  The Japan Society of Mechanical Engineers, Japanese
  DOI：https://doi.org/10.1299/jsmermd.2017.1P1-M04
  DOI ID：10.1299/jsmermd.2017.1P1-M04, CiNii Articles ID：130006220507
• Manipulation of Sense of Human Body Onwership Using Thermal Displays　　　　　　　　　　　　　　　
  HARA Masayuki; TAKAHASHI Hiroyuki; YAMAGUCHI Daisuke; ISHINO Yuji; TAKASAKI Masaya; MIZUNO Takeshi
  The Proceedings of JSME annual Conference on Robotics and Mechatronics (Robomec), Volume：2017, First page：2P1, Last page：L07, 2017
  

  Our previous studies have proposed active self-touch in which experimental participants can voluntarily touch a fake/virtual body as well as their own body by using a robotic master-salve system when experimentally manipulating sense of body ownership. This paper introduces a novel experimental platform that can control temperature displayed to the real and fake bodies by means of thermal displays in active self touch. Using the experimental platform, we aim at revealing whether the sense of body temperature is essential for human body perception and how much temperature difference between the real and fake/virtual bodies is acceptable to consider the fake/virtual body as our own body. In the present study, the basic characteristics and performances of the developed platform were evaluated and the applicability to manipulate the sense of body ownership was verified by conducting a simple cognitive neuroscientific experiment.

  
  The Japan Society of Mechanical Engineers, Japanese
  DOI：https://doi.org/10.1299/jsmermd.2017.2P1-L07
  DOI ID：10.1299/jsmermd.2017.2P1-L07, CiNii Articles ID：130006221207
• Controllability of Gyroscopic System from a Viewpoint of Parallel Magnetic Suspension　　　　　　　　　　　　　　　
  Takeshi Mizuno; Masaya Takasaki; Yuji Ishino
  2017 56TH ANNUAL CONFERENCE OF THE SOCIETY OF INSTRUMENT AND CONTROL ENGINEERS OF JAPAN (SICE), First page：1332, Last page：1335, 2017, [Reviewed]
  The controllability of gyroscopic systems is studied analytically. Two rotational motions of the rotor interact each other due to gyroscopic effects when the rotor is rotating. They are usually controlled with two control inputs in totally active magnetic bearing systems. Meanwhile, two degrees of freedom are controlled with a single control input in double parallel magnetic suspension systems. Such an approach is applied to gyroscopic systems in this article. Two rotational motions are controlled with a single control input. The conditions for gyroscopic systems to be controllable are clarified.
  IEEE, English, International conference proceedings
  Web of Science ID：WOS:000418323700289
• Development of One-Piece Zero-Compliance Mechanism for Force Measurement　　　　　　　　　　　　　　　
  Mizuno Takeshi; Takasaki Masaya; Ishino Yuji
  IFAC PAPERSONLINE, Volume：50, Number：1, First page：6067, Last page：6072, 2017, [Reviewed]
  DOI：https://doi.org/10.1016/j.ifacol.2017.08.1380
  DOI ID：10.1016/j.ifacol.2017.08.1380, ISSN：2405-8963, Web of Science ID：WOS:000423964900012
• Lateral vibration control in attractive magnetic suspension system　　　　　　　　　　　　　　　
  水野毅; JAVED Asief; 石野裕二; 高崎正也
  日本機械学会論文集(Web), Volume：83, Number：854, First page：ROMBUNNO.17‐00217(J‐STAGE), Last page：00217-17-00217, 2017, [Reviewed]
  <p>A switching stiffness control and a modified variable stiffness control were applied to reduce vibration in the lateral directions in active magnetic suspension system with electromagnets operated in the differential mode. The magnetic suspension system using the attractive force between magnetized bodies is inherently unstable in the normal direction so that feedback control is necessary to achieve stable suspension. In contrast, it is usually stable in the lateral directions because of the edge effects in the magnetic circuits. However, damping in the lateral directions is poor so that vibration is easily induced. In this work, a switching stiffness control was applied to attenuate such vibration. The effectiveness of the switching stiffness control was confirmed experimentally. In addition, a modified control method that varies stiffness continuously was proposed to overcome problems occurring in switching. The efficacy of the modified control method was also confirmed experimentally.</p>
  一般社団法人 日本機械学会, Japanese
  ISSN：2187-9761, J-Global ID：201702231634971834, CiNii Articles ID：130006181348
• Development of a wind‐tunnel for spinning body using magnetic suspension　　　　　　　　　　　　　　　
  水野毅; 酒井康博; 酒井康博; 高崎正也; 石野裕二
  日本機械学会論文集(Web), Volume：83, Number：849, First page：ROMBUNNO.16‐00482(J‐STAGE), Last page：00482-16-00482, 2017, [Reviewed]
  <p>A wind-tunnel system for spinning body has been proposed to measure hydrodynamic forces acting on the body. In the proposed system, the body is suspended and rotated by electromagnets. The forces are measured from the control signal for suspension. In the previously fabricated apparatus, eight electromagnets were placed around a wind-tunnel. An optical displacement sensor was used to detect the three-dimensional positions of the body. Stable suspension and three-dimensional positioning of the body were achieved. However, it had several problems; the test section area was rather small and vibration was induced by flowing wind to the floator. To solve such problems, a new wind-tunnel using magnetic suspension is developed. It has two and a quarter times test section area. The position sensor is improved to operate in a differential mode in all the directions. Stable suspension and rotation of the floator are achieved. The floator is kept stably without vibration even in the face of wind. The hydrodynamic forces acting on the spinning floator are measured.</p>
  一般社団法人 日本機械学会, Japanese
  ISSN：2187-9761, J-Global ID：201702286624394839, CiNii Articles ID：130005679729
• Positive‐pressure driven overflow‐prevention valve with compact trigger mechanism　　　　　　　　　　　　　　　
  水野毅; 石野裕二; 高崎正也
  日本機械学会論文集(Web), Volume：83, Number：849, First page：ROMBUNNO.16‐00558(J‐STAGE), Last page：00558-16-00558, 2017, [Reviewed]
  <p>A new over-flow prevention valve with a trigger mechanism is designed, fabricated and studied experimentally to evaluate its performances. Loading arms are used to transfer combustible fluid such as oil between tankers and tanks. A loading arm is equipped with an over-flow prevention valve for safety. This valve stops the fluid flow when the fluid exceeds a threshold level in a tank. It must be composed of mechanical elements solely because electric components may induce combustion. Therefore, it uses a pneumatic circuit to detect the fluid level and close the valve. The fabricated valve utilizes positive pressure caused by the height difference of fluid level between the tank and the sensor probe instead of negative pressure that was used in a conventional valve. However, the positive pressure is insufficient to close the valve directly. Therefore, a trigger mechanism is introduced between a piston pushed by the positive pressure and a locking mechanism keeping the valve open. This mechanism generates sufficient force to release the lock and close the main valve from the force pushing the piston. The concept, operation principles and the pneumatic circuit design are presented. Experiments simulating actual operation are carried out with the fabricated valve. The sensor probe is inserted into the water with a constant speed by a single-axis robot instead of flowing oil into the tank. The relation between the velocity and the depth when the valve closes are studied experimentally.</p>
  一般社団法人 日本機械学会, Japanese
  ISSN：2187-9761, J-Global ID：201702282091189422, CiNii Articles ID：130005679755
• Study on the delay of velocity detection and derivation of a correction formula in mass measurement using relay feedback　　　　　　　　　　　　　　　
  石橋尚宜; 水野毅; 石野裕二; 高崎正也; 山口大介; 原正之; 渡邊怜
  日本機械学会論文集(Web), Volume：83, Number：849, First page：ROMBUNNO.16‐00404(J‐STAGE), Last page：00404-16-00404, 2017, [Reviewed]
  <p>This paper treats a relay-feedback mass measurement system that uses a relay with hysteresis and feeds back the velocity of the object. The measurement system has an on-off relay with hysteresis and switches force acting on the object in relation to its velocity. Such nonlinear control induces a limit cycle. The mass of the object is determined from the period of this cycle. In previous study, the actual trajectory of the limit cycle was different in shape from the theoretical one so that the prerequisites of the estimation formula were not satisfied. The delay of the velocity sensor is a main factor of such degradation. In this paper, the effect of the delay on mass estimation is investigated experimentally and analytically. In addition, an estimating equation including this effect is derived. Experimental result supports the validity of the derived estimating equation.</p>
  一般社団法人 日本機械学会, Japanese
  ISSN：2187-9761, J-Global ID：201702217088795773, CiNii Articles ID：130005679749
• Structure for Ultrasonic Suspension Gap Pressure Sensor　　　　　　　　　　　　　　　
  Takasaki Masaya; Chida Ryutaro; Chino Shota; Morishita Satoshi; Ishino Yuji; Hosaka Kota; Mita Yoshio; Mizuno Takeshi
  SENSORS AND MATERIALS, Volume：29, Number：6, First page：805, Last page：816, 2017, [Reviewed]
  DOI：https://doi.org/10.18494/SAM.2017.1471
  DOI ID：10.18494/SAM.2017.1471, ISSN：0914-4935, Web of Science ID：WOS:000419748900005
• Pump using ultrasonic transducer and opposing surface (1st report : observation of pump effect)　　　　　　　　　　　　　　　
  H. Shinada; Y. Ishino; D. Yamaguchi; M. Hara; M. Takasaki; T. Mizuno
  Transactions of the JSME, Volume：83, Number：845, First page：16-00278, Jan. 2017, [Reviewed]
  Japanese, Scientific journal
  DOI：https://doi.org/10.1299/transjsme.16-00278
  DOI ID：10.1299/transjsme.16-00278
• Lateral Vibration Attenuation by the Dynamic Adjustment of Bias Currents in Magnetic Suspension System　　　　　　　　　　　　　　　
  Takeshi Mizuno; Masaya Takasaki; Yuji Ishino
  Journal of Physics: Conference Series, Volume：744, Number：1, Oct. 2016, [Reviewed]
  Switching stiffness control is applied to attenuate vibration in the lateral directions in an active magnetic suspension system with electromagnets operated in differential mode. The magnetic suspension system using the attractive force between magnetized bodies is inherently unstable in the normal direction so that feedback control is necessary to achieve stable suspension. In contrast, it can be stable in the lateral directions due to the edge effects in the magnetic circuits. In several applications, such passive suspension is used in combination with the active one to reduce cost and space. However, damping in the lateral directions is generally small. As a result, induced vibrations in these directions are hardly attenuated. To suppress such vibration without any additional actuator (electromagnet), switching stiffness control is applied to an magnetic suspension system operated in the differential mode. The stiffness in the lateral direction is adjusted by varying the bias currents of an opposed pair of electromagnets located in the normal direction simultaneously according to the motion of the suspended object. When the varied bias currents are adjusted for the additive normal forces cancel each other, such control does not affect the suspension in the normal direction. The effectiveness of the proposed control methods is confirmed experimentally.
  Institute of Physics Publishing, English, International conference proceedings
  DOI：https://doi.org/10.1088/1742-6596/744/1/012005
  DOI ID：10.1088/1742-6596/744/1/012005, ISSN：1742-6596, SCOPUS ID：84994176271
• Development of Overflow-Prevention Valve with Trigger Mechanism.　　　　　　　　　　　　　　　
  Yuji Ishino; Takeshi Mizuno; Masaya Takasaki
  Journal of Physics: Conference Series, Volume：744, Number：1, Oct. 2016, [Reviewed]
  A new overflow-prevention valve for combustible fluid is developed which uses a trigger mechanism. Loading arms for combustible fluid are used for transferring oil from a tanker to tanks and vice versa. The loading arm has a valve for preventing overflow. Overflow- prevention valves cannot use any electric component to avoid combustion. Therefore, the valve must be constructed only by mechanical parts. The conventional overflow-prevention valve uses fluid and pneumatic forces. It consists of a sensor probe, a cylinder, a main valve for shutting off the fluid and a locking mechanism for holding an open state of the main valve. The proposed overflow-prevention valve uses the pressure due to the height difference between the fluid level of the tank and the sensor probe. However, the force of the cylinder produced by the pressure is too small to release the locking mechanism. Therefore, a trigger mechanism is introduced between the cylinder and the locking mechanism. The trigger mechanism produces sufficient force to release the locking mechanism and close the main valve when the height of fluid exceeds a threshold value. A trigger mechanism is designed and fabricated. The operation necessary for closing the main valve is conformed experimentally.
  Institute of Physics Publishing, English, International conference proceedings
  DOI：https://doi.org/10.1088/1742-6596/744/1/012096
  DOI ID：10.1088/1742-6596/744/1/012096, ISSN：1742-6596, SCOPUS ID：84994067097
• CONTROLLABILITY AND OBSERVABILITY OF PARALLEL MAGNETIC SUSPENSION SYSTEMS　　　　　　　　　　　　　　　
  Takeshi Mizuno; Masaya Takasaki; Yuji Ishino
  ASIAN JOURNAL OF CONTROL, Volume：18, Number：4, First page：1313, Last page：1327, Jul. 2016, [Reviewed]
  The controllability and observability of parallel magnetic suspension systems are investigated analytically. A parallel magnetic suspension system has multiple floators and electromagnets driven by a single amplifier. In this paper, the multiplicity is set to an arbitrary counting number n. Parallel systems are classified into four types based on the output of the power amplifier and the connection of the coils. This paper treats three of them: current-controlled with series-connected coils; voltage-controlled with series-connected coils; and voltage-controlled with parallel-connected coils. The conditions of controllability and observability of each system are clarified. The feasibility of parallel magnetic suspension is demonstrated by simulations and experiments.
  WILEY-BLACKWELL, English, Scientific journal
  DOI：https://doi.org/10.1002/asjc.1263
  DOI ID：10.1002/asjc.1263, ISSN：1561-8625, eISSN：1934-6093, Web of Science ID：WOS:000383696100011
• Application of Frequency-Following Servocompensator to Unbalance Compensation in Gyro With Flexures Gimbal　　　　　　　　　　　　　　　
  Takeshi Mizuno; Tomohiro Akiyama; Masaya Takasaki; Yuji Ishino
  IEEE-ASME TRANSACTIONS ON MECHATRONICS, Volume：21, Number：2, First page：1151, Last page：1159, Apr. 2016, [Reviewed]
  A frequency-following servocompensator is applied to a rotary gyro with flexures gimbal to eliminate the oscillating components from the estimated signals. In the targeted gyro, a synchronous motor is fixed to a rectangular holder and a disk-type rotor is driven by the motor to generate gyroscopic couplings. The coupled two rotational motions of the holder are controlled by four electromagnets on the stator; the angular velocities are estimated from the control currents to regulate the relative displacement of the holder to the stator. The other four-degree-of-freedom motions of the holder are constrained by the flexures gimbal. Such suspension using flexures makes the system less damped so that high accuracy is expected to this gyro. However, one of the problems is that an oscillating component caused by rotor unbalance appears in the estimated signal because the estimation is based on the control input. To solve this problem, the frequency-tracking servocompensator is applied to eliminate the oscillating component. The virtually perfect elimination of the component from the estimated signal was achieved.
  IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, English, Scientific journal
  DOI：https://doi.org/10.1109/TMECH.2015.2497261
  DOI ID：10.1109/TMECH.2015.2497261, ISSN：1083-4435, eISSN：1941-014X, Web of Science ID：WOS:000372368700052
• Evaluation of Polyimide Film Welding for Improving Performance of Pneumatic Film Actuator　　　　　　　　　　　　　　　
  Kamimura Ryotaro; Yamaguchi Daisuke; Hanaki Tatsuya; Hara Masayuki; Ishino Yuji; Takasaki Masaya; Mizuno Takeshi
  Proceedings of JSPE Semestrial Meeting, Volume：2016, First page：411, Last page：412, 2016
  低温脆性を持つ試料等を低温環境下で操作するアクチュエータの需要が高まっている．これまでに，液体窒素温度環境下で駆動する空圧アクチュエータの試作を行った．このアクチュエータはポリイミドフィルム同士の溶着により製作され，アクチュエータの耐久性や性能には溶着部の状態が大きく影響する．そこで本研究では，ポリイミドフィルム溶着部の評価を行い，アクチュエータに適した溶着条件の選定を行った．
  The Japan Society for Precision Engineering, Japanese
  DOI：https://doi.org/10.11522/pscjspe.2016S.0_411
  DOI ID：10.11522/pscjspe.2016S.0_411, CiNii Articles ID：130005263975
• Force Compensation for Anti-collision in Placing a Magnetized Component on Ferromagnetic Plate　　　　　　　　　　　　　　　
  Takeshi Mizuno; Yuji Ishino; Masaya Takasaki
  2016 EUROPEAN CONTROL CONFERENCE (ECC), First page：1556, Last page：1561, 2016, [Reviewed]
  A positioning device for placing a magnetized component on a ferromagnetic plate without collision has been fabricated. When the magnetized component approaches to the plate, the attractive force between them increases sharply as the gap decreases. It sometimes causes them to collide. To prevent such collision, a force compensation control is applied to cancel such nonlinear disturbance force by the actuator driving the component. In addition, a command revision control is implemented to avoid collision even in the presence of errors in modeling and positioning. The effectiveness of the proposed control schemes is demonstrated experimentally.
  IEEE, English, International conference proceedings
  Web of Science ID：WOS:000392695300259
• Fabrication of a Three-dimensional Force Measurement System Using Double Series Magnetic Suspension　　　　　　　　　　　　　　　
  Takeshi Mizuno; Yuji Ishino; Masaya Takasaki
  IFAC PAPERSONLINE, Volume：49, Number：21, First page：536, Last page：540, 2016, [Reviewed]
  Double series magnetic suspension is applied to force measurement. In a double series magnetic suspension system, two floators are suspended with a single electromagnet. When the position of the second floator is regulated, for example by PID control, the second floator is maintained at the original position against an external force acting on it whereas the first floator displaces in proportional to the force. Therefore, the force acting on the second floator can be estimated for the displacement of the first floator. This principle of force measurement was applied to single-dimensional force measurement. In this work, an apparatus for three-dimensional force measurement is designed and fabricated. An individual three-axis control is applied to the apparatus to achieve noncontact suspension. Then, three-dimensional force measurements are carried out to study the performances of the fabricated apparatus. (C) 2016, IFAC (International Federation of Automatic Control) Hosting Elsevier Ltd. All rights reseirved.
  ELSEVIER SCIENCE BV, English, International conference proceedings
  DOI：https://doi.org/10.1016/j.ifacol.2016.10.657
  DOI ID：10.1016/j.ifacol.2016.10.657, ISSN：2405-8963, Web of Science ID：WOS:000401247700078
• Electromagnetic analysis in magnetic suspension mechanism of a wind tunnel for spinning body　　　　　　　　　　　　　　　
  Shahajada Mahmudul Hasan; Takeshi Mizuno; Masaya Takasaki; Yuji Ishino
  INTERNATIONAL JOURNAL OF APPLIED ELECTROMAGNETICS AND MECHANICS, Volume：52, Number：1-2, First page：231, Last page：241, 2016, [Reviewed]
  A wind tunnel system for a spinning body has been designed for the measurement of the hydrodynamic forces acting on the body. The body was successfully suspended and rotated by electromagnets. This existing arrangement is required to be enlarged to observe more accurate hydrodynamic forces acting on the body. Therefore, for the further development and control, it is important to understand the exact magnetic flux distribution inside the system as well as the variation of the force with the increase of the current. In this paper, both 2D symmetric model and 3D model of the arrangement are taken in consideration for the analysis. The magnetic flux distributions as well as magnetic force acting on the suspended object are obtained. The magnetic flux densities are analyzed for the variation of current in electromagnets. Actual force acting on the body is also measured. It is observed that the experimental results support the results obtained by numerical analysis.
  IOS PRESS, English, Scientific journal
  DOI：https://doi.org/10.3233/JAE-162077
  DOI ID：10.3233/JAE-162077, ISSN：1383-5416, eISSN：1875-8800, Web of Science ID：WOS:000391965800030
• Design and Fabrication of an Enlarged Wind Tunnel System for Spinning Body Using Magnetic Suspension　　　　　　　　　　　　　　　
  HASAN Shahajada Mahmudul; MIZUNO Takeshi; TAKASAKI Masaya; ISHINO Yuji; HARA Masayuki; YAMAGUCHI Daisuke
  Journal of the Japan Society of Applied Electromagnetics and Mechanics, Volume：24, Number：3, First page：264, Last page：270, 2016, [Reviewed]
  <p>A wind tunnel system for a spinning body was developed for the measurement of the hydrodynamic forces acting on the body. In that system a ferromagnetic sphere (body) was suspended and rotated by electromagnets. The forces acting on the body were measured from the control signal for suspension. However this existing arrangement is not still appropriate to observe accurate hydrodynamic phenomena around the floating object because the size of the wind tunnel is only 60×60mm. It is required to enlarge the size to reduce the interferences with the walls. In this work, a wind-tunnel system of 100×100mm is proposed to be fabricated. Before the development of the system, the electromagnetic analysis for the system has been carried out. A 3D model of the arrangement is taken in consideration for the analysis. The magnetic flux distributions as well as magnetic force acting on the suspended object are obtained. The magnetic flux densities are analyzed for the variation of current in electromagnets. Actual force acting on the body is also measured. It is observed that the experimental results support the results obtained by numerical analysis. Stable suspension and three-dimensional positioning of the body is achieved in the developed system. Spinning of the body is realized by superimposing two-phase AC signals on the control signal.</p>
  日本AEM学会, English
  ISSN：0919-4452, CiNii Articles ID：130005252911
• Novel AC magnetic suspension using magnetic resonant coupling　　　　　　　　　　　　　　　
  Mizuno Takeshi; Takahashi Kei; Ishino Yuji; Takasaki Masaya
  MECHANICAL ENGINEERING JOURNAL, Volume：3, Number：2, 2016, [Reviewed]
  DOI：https://doi.org/10.1299/mej.15-00687
  DOI ID：10.1299/mej.15-00687, ISSN：2187-9745, Web of Science ID：WOS:000434619900020
• A Simple Action of Right Index Finger Induces Rubber Hand Illusion to Static Left Hand　　　　　　　　　　　　　　　
  Masayuki Hara; Noariaki Kanayama; Daisuke Yamaguchi; Yuji Ishino; Masaya Takasaki; Takeshi Mizuno
  2016 IEEE INTERNATIONAL CONFERENCE ON SYSTEMS, MAN, AND CYBERNETICS (SMC), First page：737, Last page：742, 2016, [Reviewed]
  The rubber hand illusion (RHI) is a bodily illusion that a fake rubber hand is felt as if it was one's own hand when both the hands are synchronously stimulated. Also, it is well-known that people can experience the RHI when the movements of the visible fake and invisible real hands are synchronized. However, underlying mechanism of the RHI and relationship between action and body ownership are still open questions. Based on the RHI paradigm, the present paper discusses how the agency of a body part affects the sense of body ownership at the other body part. In this study, we examined if a simple up-and-down action of right index finger induces the RHI to left hand which was kept still by using virtual reality and robotics technologies. Our experimental results indicated that the action of the right index finger allowed the embodiment of the virtual hands at both the right and left hands. This implies that only a simple action of a body part increases the sense of body ownership at the other body part.
  IEEE, English, International conference proceedings
  DOI：https://doi.org/10.1109/SMC.2016.7844329
  DOI ID：10.1109/SMC.2016.7844329, ISSN：1062-922X, ORCID：46517613, SCOPUS ID：85015788278, Web of Science ID：WOS:000402634700113
• Proposal of lateral vibration control based on force detection in magnetic suspension system　　　　　　　　　　　　　　　
  Asief Javed; Takeshi Mizuno; Masaya Takasaki; Yuji Ishino; Masayuki Hara; Daisuke Yamaguchi
  INTERNATIONAL JOURNAL OF APPLIED ELECTROMAGNETICS AND MECHANICS, Volume：52, Number：1-2, First page：223, Last page：229, 2016, [Reviewed]
  A method of suppressing vibration in lateral directions is investigated based on varying stiffness strategy. A vertically controlled magnetic suspension system is often subjected to vibration in lightly damped lateral directions. In this paper, a novel approach is proposed to detect the lateral displacement of such magnetic suspension system, and how this displacement can be used to reduce vibration by varying stiffness control is presented. The principle of edge effect is applied to detect the lateral displacement in a magnetic suspension system operated in differential mode. A switching stiffness control and a modified control strategies are used to vary the stiffness of the system in order to reduce lateral vibration. Several experiments are carried out to validate the efficiency of the proposed method.
  IOS PRESS, English, Scientific journal
  DOI：https://doi.org/10.3233/JAE-162064
  DOI ID：10.3233/JAE-162064, ISSN：1383-5416, eISSN：1875-8800, Web of Science ID：WOS:000391965800029
• Active vibration isolation using negative stiffness and displacement cancellation controls: Comparison based on vibration isolation performance　　　　　　　　　　　　　　　
  Mhia Md. Zaglul Shahadat; Takeshi Mizuno; Yuji Ishino; Masaya Takasaki
  CONTROL ENGINEERING PRACTICE, Volume：37, First page：55, Last page：66, Apr. 2015, [Reviewed]
  Two vibration control techniques, negative stiffness and displacement cancellation, are characterized and employed to achieve active vibration isolation. A horizontal vibration isolation system is developed and then used to investigate each of these techniques theoretically and experimentally. The respective responses of the developed system are measured separately while closed-loop poles of the system are kept unchanged; these measured responses are compared. The developed system is based on a series combination of two isolators and consists of two moving tables; one of the moving tables is mounted on the series-connected isolators and the other is placed between the isolators. Using the negative stiffness technique, the isolators are controlled so that one of them has a negative stiffness and the other has a positive stiffness of equal absolute magnitude; using the displacement cancellation technique, one isolator is set to cancel displacement while the other behaves as a positive-stiffness isolator. The active negative, positive, and displacement cancellation isolators are created using voice-coil motors guided by a negative stiffness controller, proportional derivative controller and integral-proportional derivative controller, respectively. (C) 2014 Elsevier Ltd. All rights reserved.
  PERGAMON-ELSEVIER SCIENCE LTD, English, Scientific journal
  DOI：https://doi.org/10.1016/j.conengprac.2014.12.004
  DOI ID：10.1016/j.conengprac.2014.12.004, ISSN：0967-0661, eISSN：1873-6939, Web of Science ID：WOS:000351980300006
• Development of Non-contact Carrier System using Solar Magnetic Suspension (3ed report: Continuous 5-day and installation of sloping propulsion mechanism)　　　　　　　　　　　　　　　
  Yuji Ishino; Takeshi Mizuno; Masaya Takasaki; Masayuki Hara; Daisuke Yamaguchi
  2015 10TH ASIAN CONTROL CONFERENCE (ASCC), 2015, [Reviewed]
  A solar-powered magnetic suspension carrier system is developed in which the carrier is powered without contact. There are two conventional methods of powering the coils of the magnetic suspension carrier: (i) through wire, (ii) onboard battery (wireless) power supply. The contactless is lost in the former while stations for charging the battery are necessary in the latter. These problems are overcome by the proposed carrier system using solar magnetic suspension that can attain continuous levitation. The magnetic suspension carrier is assumed to operate inside rooms like inside a factory building. Because the generation power by solar cells is small, power saving us acritical requirement. Therefore, the zero power control is applied for suspension. In addition, low-power peripheral devices are fabricated. The developed carrier system achieved a five-day levitation without external power supply in a bright environment. In addition, a sloping propulsion mechanism was introduced. The mechanism consists of a track rail and two pillars with actuators to move up and down the track rail. The carrier slides and moves to the lower direction due to gravity below a sloped rail.
  IEEE, English, International conference proceedings
  Web of Science ID：WOS:000388123000253
• Design of Bolt-clamped Langevin-type transducer for haptic device in high magnetic field　　　　　　　　　　　　　　　
  Yamaguchi Daisuke; Hara Masayuki; Ishino Yuji; Takasaki Masaya; Mizuno Takeshi
  Proceedings of JSPE Semestrial Meeting, Volume：2015, First page：585, Last page：586, 2015
  本研究ではこれまでに，スクイーズ膜効果を利用した触覚呈示装置に関して研究を行っている．MRIなど強磁場環境下に本触覚呈示装置を適用することができれば，触覚と脳活動の関係にまで議論を進めることができるものと考える．そこで本稿では，触覚呈示装置の駆動源であるボルト締めランジュバン型振動子について，強磁場環境下における使用を目的とした試作設計を行った．
  The Japan Society for Precision Engineering, Japanese
  DOI：https://doi.org/10.11522/pscjspe.2015S.0_585
  DOI ID：10.11522/pscjspe.2015S.0_585, CiNii Articles ID：130005486406
• Efficiency evaluation method for vibration energy harvesting by piezoelectric transducer　　　　　　　　　　　　　　　
  Sato Fumiki; Zhang Shuo; Ishino Yuji; Hara Masayuki; Yamaguchi Daisuke; Takasaki Masaya; Mizuno Takeshi
  Proceedings of JSPE Semestrial Meeting, Volume：2015, First page：969, Last page：970, 2015
  圧電振動子を組み込んだ発電機構での圧電振動子の発電効率を評価する方法を提案する．発電機構の圧電振動子に負荷抵抗を接続した時を発電状態，接続していない時を非発電状態とする．発電機構に振動を与えた時，その２つの状態で圧電振動子の変形量を等しくすることで各状態での発電機構に与えたエネルギの差を入力エネルギとして同定する．出力エネルギは負荷抵抗で消費される電気エネルギとすることで発電効率を測定した．
  The Japan Society for Precision Engineering, Japanese
  DOI：https://doi.org/10.11522/pscjspe.2015S.0_969
  DOI ID：10.11522/pscjspe.2015S.0_969, CiNii Articles ID：130005486620
• Proposal of Pump Using Ultrasonic Transducer and Opposing Surface　　　　　　　　　　　　　　　
  H. Shinada; Y. Ishino; M. Hara; D. Yamaguchi; M. Takasaki; T. Mizuno
  Physics Procedia, Volume：70, First page：76, Last page：79, 2015
  Elsevier BV, Scientific journal
  DOI：https://doi.org/10.1016/j.phpro.2015.08.046
  DOI ID：10.1016/j.phpro.2015.08.046, ISSN：1875-3892
• Realization of Acceleration Feedback by Using an Active Dynamic Vibration Absorber as a Sensor in a Low-frequency Region　　　　　　　　　　　　　　　
  Takeshi Mizuno; Hiroaki Sekiya; Yuji Ishino; Masaya Takasaki
  2015 EUROPEAN CONTROL CONFERENCE (ECC), First page：1681, Last page：1685, 2015, [Reviewed]
  An active vibration isolation system has been proposed which uses an active dynamic vibration absorber as a servo accelerometer in a low-frequency range and as a vibration control device in a high-frequency range. Complimentarily, it uses an air actuator as a control device in a low-frequency range and a low-cost MEMS accelerometer as a sensing device in a high-frequency range. The main aim of this research is to develop a high performance active vibration isolation system that is lower in cost than conventional active vibration system. It is experimentally demonstrated that the acceleration in a low frequency range is estimated from the control signal of the absorber and the vibration is actually attenuated by feeding back the estimated acceleration.
  IEEE, English, International conference proceedings
  Web of Science ID：WOS:000380485400263
• Parallel-Mechanism Based Vibration Isolation System Using Displacement Cancellation Control　　　　　　　　　　　　　　　
  Mhia Md Zaglul Shahadat; Takeshi Mizuno; Masaya Takasaki; Yuji Ishino
  2015 10TH ASIAN CONTROL CONFERENCE (ASCC), 2015, [Reviewed]
  A vibration isolation system based on parallel-mechanism is developed. The responses of the developed system against a disturbance are investigated analytically and experimentally. The developed system consists of six individual vibration isolation units of single degree-of-freedom which are placed in parallel between a common vibration isolation table and base; consequently, the common vibration isolation table has six-degrees-of-freedom motions to be controlled by the units. The individual units are fabricated based on series combination of two isolators that use magnetic suspension. The two series connected magnetic suspensions in each unit are controlled according to displacement cancellation principle; one of them behaves as a displacement cancellation isolator and the other behaves as a positive stiffness isolator.
  IEEE, English, International conference proceedings
  Web of Science ID：WOS:000388123000385
• Mass measurement using the fixed-point of a spring-mass system with a dynamic vibration absorber and an inertial-mass vibrator　　　　　　　　　　　　　　　
  Korikawa Tomoyuki; Ishino Yuji; Takasaki Masaya; Mizuno Takeshi
  MECHANICAL ENGINEERING JOURNAL, Volume：2, Number：5, 2015, [Reviewed]
  DOI：https://doi.org/10.1299/mej.14-00565
  DOI ID：10.1299/mej.14-00565, ISSN：2187-9745, Web of Science ID：WOS:000434619200006
• Fabrication of non-contact carrier system using solar magnetic suspension　　　　　　　　　　　　　　　
  Ishino Yuji; Takasaki Masaya; Mizuno Takeshi
  MECHANICAL ENGINEERING JOURNAL, Volume：2, Number：4, 2015, [Reviewed]
  DOI：https://doi.org/10.1299/mej.15-00143
  DOI ID：10.1299/mej.15-00143, ISSN：2187-9745, Web of Science ID：WOS:000434618900015
• Realization of diamagnetic levitation of column-shaped graphite　　　　　　　　　　　　　　　
  Iida Keisuke; Narisawa Yoshinori; Ishino Yuji; Takasaki Masaya; Mizuno Takeshi
  MECHANICAL ENGINEERING JOURNAL, Volume：2, Number：3, 2015, [Reviewed]
  DOI：https://doi.org/10.1299/mej.14-00559
  DOI ID：10.1299/mej.14-00559, ISSN：2187-9745, Web of Science ID：WOS:000434617000017
• Development of a Rotary Gyro with Hybrid Suspension　　　　　　　　　　　　　　　
  水野毅; 秋山智広; 高崎正也; 石野裕二
  精密工学会誌(Web), Volume：81, Number：4, First page：356-362 (J-STAGE), Last page：362, 2015, [Reviewed]
  A new configuration for rotating gyros using magnetic suspension is proposed and fabricated. Gyro is one of inertial sensors and a measuring instrument for angular velocity. The magnetically suspended gyro (MSG) was proposed in which a disk-type rotor is connected to a synchronous motor through a fluid bearing and the motor is fixed to the holder; the holder is suspended by magnetic force without any mechanical contact to achieve high-accuracy measurement. According to this concept, a six-degree-of-freedom (6-DOF) active MSG was developed. However, the MSG had to consume power for compensating the gravitational force acting on the holder by magnetic force. In addition, the miniaturization of the MSG was difficult because four pairs of electromagnets were arranged on the opposite sides of the holder. To solve these problems, a novel gyro with hybrid suspension is designed and fabricated. In this gyro, only two rotational motions of the holder are controlled by four electromagnets while the other 4-DOF motions of the holder are constrained by cross springs and a gimbal. Such configuration is suitable for reducing power consumption and also for miniaturization. This paper shows the basic concepts and measurement principles of the rotary gyro with hybrid suspension. The performance of the gyro is evaluated through the measurement of two-axis angular velocities. It is found from the measured frequency characteristics and the succeeding analysis that imperfect derivatives used in the estimation cause an interaction between the two-axis estimations. Two ways to cope with this problem are also presented.
  公益社団法人 精密工学会, Japanese
  DOI：https://doi.org/10.2493/jjspe.81.356
  DOI ID：10.2493/jjspe.81.356, ISSN：1882-675X, J-Global ID：201502238237638773, CiNii Articles ID：130005060674
• Development of a totally active magnetically suspended gyro　　　　　　　　　　　　　　　
  Tomohiro Akiyama; Takeshi Mizuno; Masaya Takasaki; Yuji Ishino; Kyosuke Obara
  MECHATRONICS, Volume：24, Number：8, First page：1059, Last page：1070, Dec. 2014, [Reviewed]
  A magnetically suspended gyro (MSG) is developed and its performances is estimated. In the MSG, a disk-type rotor is connected to a synchronous motor through a fluid bearing and the motor is fixed to the frame of the floator. The floator is suspended by magnetic force without any mechanical contact so that highly accurate measurement is possible. In accordance with this concept, a three-degrees-of-freedom (DOE) active MSG was developed. However, because of poor damping in the passive suspension and the low resolution of the displacement sensors, the measurement accuracy was relatively low. To solve these problems, a six-DOF (totally) active MSG is designed and fabricated. The frame of this gyro is an octagonal. The motion of the frame is controlled by eight electromagnets. The performance of the gyro is evaluated through measurement of the double-axis angular velocity. The advantages of totally active suspension are investigated. Sufficient damping rapidly reduces the influence of disturbances. Then, the influence of sensor noise is examined. The results of this examination show that the accuracy of the angular velocity measurement is improved by using highly sensitive displacement sensors. Next, the dynamic range is measured. This experiment shows that the MSG can provide precise angular velocity measurement in a low-frequency region. (C) 2014 Elsevier Ltd. All rights reserved.
  PERGAMON-ELSEVIER SCIENCE LTD, English, Scientific journal
  DOI：https://doi.org/10.1016/j.mechatronics.2014.06.004
  DOI ID：10.1016/j.mechatronics.2014.06.004, ISSN：0957-4158, Web of Science ID：WOS:000347499900017
• Enlargement of floator size in ultrasonic suspension by arranging the shape of vibrating surface　　　　　　　　　　　　　　　
  Kota Uchiage; Yuji Ishino; Masaya Takasaki; Takeshi Mizuno
  IEEE International Ultrasonics Symposium, IUS, First page：2510, Last page：2513, Oct. 2014, [Reviewed]
  In near-field acoustic levitation, an object can be levitated vertically upward above vibrating surface of an ultrasonic transducer. On the other hand, it has been reported that an object can be suspended vertically downward under the vibrating surface in the air. We call this phenomenon ultrasonic suspension. When an object is suspended, there is restoring force, which attracts the object to the center of the vibrating surface. By using ultrasonic suspension in handling objects, we have some merits such as non-contact, easy release, material independence, possibility of approaching from above the object and so on. In previous research, the attractive force acting on the object has been measured under the ultrasonic suspension. According to measurement results, it was found that by enlarging the size of facing area of vibrating surface and floator, the actuation force was not the larger attractive force but the repulsive force. In this paper, arrangement of the shape of vibrating surface is discussed and method for enlargement of the size of the floator is proposed.
  IEEE Computer Society, English, International conference proceedings
  DOI：https://doi.org/10.1109/ULTSYM.2014.0626
  DOI ID：10.1109/ULTSYM.2014.0626, ISSN：1948-5727, SCOPUS ID：84910071873
• Effect of Nonlinearity Caused by Friction on a Negative Stiffness Control System　　　　　　　　　　　　　　　
  Mhia Md Zaglul Shahadat; Takeshi Mizuno; Yuji Ishino; Masaya Takasaki
  IEEE TRANSACTIONS ON CONTROL SYSTEMS TECHNOLOGY, Volume：22, Number：4, First page：1385, Last page：1395, Jul. 2014, [Reviewed]
  The effect of friction on a negative stiffness control system is investigated. The negative stiffness control system is used to obtain zero compliance needed for a vibration isolation system. However, the performance of a negative stiffness control system is significantly affected by friction. In this paper, the friction-induced limit cycle in a negative stiffness control system is identified theoretically through describing function approach. Moreover, the relationship between the magnitude of the control parameters used in designing the negative stiffness controller and the behaviors of the induced limit cycle is determined. Finally, the theoretical limit cycle is verified with an experimental limit cycle measured by the time response to the self-oscillation of the system.
  IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, English, Scientific journal
  DOI：https://doi.org/10.1109/TCST.2013.2286815
  DOI ID：10.1109/TCST.2013.2286815, ISSN：1063-6536, eISSN：1558-0865, DBLP ID：journals/tcst/ShahadatMIT14, Web of Science ID：WOS:000338193100012
• Application of Unbalance Compensation to a Rotary Gyro with Hybrid Suspension　　　　　　　　　　　　　　　
  秋山智広; 水野毅; 高崎正也; 石野裕二
  日本AEM学会誌, Volume：22, Number：2, First page：220, Last page：225, Jun. 2014, [Reviewed]
  This paper presents an application of unbalance compensation to a rotary gyro with hybrid suspension. In this gyro, a disk-type rotor is connected to a synchronous motor through a fluid bearing and the motor is fixed to the frame of the holder. The four-degree-of-freedom motions of the holder are constrained by a cross spring and a gimbal. The two rotational motions of the holder are controlled by four electromagnets. Such hybrid suspension makes the system less damped. Therefore, high-accuracy measurement is possible by this gyro. However, one of the problems is that an oscillating component due to unbalance appears in the estimated angular velocity because the estimation is based on the control currents for regulating the relative displacement of the holder to the stator. To solve this problem, unbalance compensation is applied to remove the oscillating component. It is confirmed experimentally that the estimated signal agrees well with the reference signal.
  日本AEM学会, Japanese
  DOI：https://doi.org/10.14243/jsaem.22.220
  DOI ID：10.14243/jsaem.22.220, ISSN：0919-4452, J-Global ID：201402244012220489, CiNii Articles ID：130004698698
• Retrofitting a passive vibration isolation system with zero-compliance modules　　　　　　　　　　　　　　　
  Takeshi Mizuno; Yuji Ishino; Masaya Takasaki
  IFAC Proceedings Volumes (IFAC-PapersOnline), Volume：19, First page：4748, Last page：4753, 2014
  A vibration isolation module with zero-power magnetic suspension is developed to retrofit a passive vibration isolation system to improve the performance against direct disturbance. In the module, the zero-power magnetic suspension mechanism is connected in series with a normal spring through a middle mass. This structure can generate zero compliance to direct disturbance while the transmitted vibration is still reduced. Such zero-compliance module was actually designed and fabricated. The characteristics of the fabricated module were studied experimentally. A passive vibration isolation system using air springs were retrofitted with four modules. It was demonstrated that the performance against direct disturbance was improved significantly.
  IFAC Secretariat, English, International conference proceedings
  DOI：https://doi.org/10.3182/20140824-6-za-1003.00157
  DOI ID：10.3182/20140824-6-za-1003.00157, ISSN：1474-6670, SCOPUS ID：84929833810
• Solar magnetic suspension carrier system --2nd report: Mesured leavitation characteristics　　　　　　　　　　　　　　　
  Ishino Yuji; Yamaguchi Daisuke; Takasaki Masaya; Mizuno Takeshi
  Proceedings of the Japan Joint Automatic Control Conference, Volume：57, First page：74, Last page：78, 2014
  磁気浮上搬送車では，搬送車側に電力を供給する方法として従来パンタグラフのような一部接触を許す方法が用いられてきた．本研究では，太陽光発電技術を応用し電力を供給して，完全非接触である搬送装置の製作と特性を取得した．
  The Japan Joint Automatic Control Conference, Japanese
  DOI：https://doi.org/10.11511/jacc.57.0_74
  DOI ID：10.11511/jacc.57.0_74, CiNii Articles ID：130005146062
• Comparison of the behavior of different feedback approaches applied to a double parallel magnetic suspension system with parallel connected coils　　　　　　　　　　　　　　　
  Narisawa Yoshinori; Ishino Yuji; Takasaki Masaya; Mizuno Takeshi
  Proceedings of the Japan Joint Automatic Control Conference, Volume：57, First page：79, Last page：80, 2014
  著者らは，単一の電磁石あるいは単一のアンプを用いて複数の浮上体を同時に制御する多重式磁気浮上システムを提案し，その基本特性を明らかにしている．電圧制御型並列接続式並列二重磁気浮上システムにおけるゼロパワー制御では，制御電圧，片側のコイル電流，およびコイル電流の和の積分値を局所フィードバックする方式のコントローラが考えられる．本報では，これら三つの方式のゼロパワーコントローラを内包したシステムにおいて，極配置を用いた比較を行った結果を報告する．
  The Japan Joint Automatic Control Conference, Japanese
  DOI：https://doi.org/10.11511/jacc.57.0_79
  DOI ID：10.11511/jacc.57.0_79, CiNii Articles ID：130005146143
• Reduction of Noise in MEMS Output Signals by Kalman-filter Estimation　　　　　　　　　　　　　　　
  Shahadat Mhia Md Zaglul; Mizuno Takeshi; Ishino Yuji; Takasaki Masaya
  Proceedings of the Japan Joint Automatic Control Conference, Volume：57, First page：1276, Last page：1278, 2014
  In many mechanical control systems, the addition of acceleration feedback to the controller is an effective approach to improve systems dynamics irrespective to disturbances on them. The servo accelerometers are commonly used to measure acceleration accurately in a low frequency range; however, a conventional servo accelerometer attached to a system to measure acceleration makes the system rather costlier. The use of low-cost Micro-Electromechanical System (MEMS) accelerometers to measure acceleration can overcome this difficulty; however, the acceleration signals measured by a MEMS accelerometer typically contain noise. In this study, the Kalman filter technique is applied to reduce such noise as well as to make the MEMS accelerometers suitable to use in an active system. The Kalman filter technique used in this study estimates acceleration by minimizing the mean-square error of a series of measurements conducted by MEMS accelerometer over time, containing noise (random variations) and other inaccuracies. It is observed that the estimated accelerations by using the Kalman filter tend more precise than those based on measurement.
  The Japan Joint Automatic Control Conference, Japanese
  DOI：https://doi.org/10.11511/jacc.57.0_1276
  DOI ID：10.11511/jacc.57.0_1276, CiNii Articles ID：130005145878
• Retrofitting A Passive Vibration Isolation System with Zero-Compliance Modules　　　　　　　　　　　　　　　
  Takeshi Mizuno; Yuji Ishino; Masaya Takasaki
  IFAC PAPERSONLINE, Volume：47, Number：3, First page：4748, Last page：4753, 2014, [Reviewed]
  A vibration isolation module with zero-power magnetic suspension is developed to retrofit a passive vibration isolation system to improve the performance against direct disturbance. In the module, the zero-power magnetic suspension mechanism is connected in series with a normal spring through a middle mass. This structure can generate zero compliance to direct disturbance while the transmitted vibration is still reduced. Such zero-compliance module was actually designed and fabricated. The characteristics of the fabricated module were studied experimentally. A passive vibration isolation system using air springs were retrofitted with four modules. It was demonstrated that the performance against direct disturbance was improved significantly.
  ELSEVIER SCIENCE BV, English, International conference proceedings
  ISSN：2405-8963, Web of Science ID：WOS:000391107600282
• Zero-power Control of Double Parallel Magnetic Suspension System with Mixed Polarity　　　　　　　　　　　　　　　
  Takeshi Mizuno; Yuji Ishino; Masaya Takasaki
  IECON 2014 - 40TH ANNUAL CONFERENCE OF THE IEEE INDUSTRIAL ELECTRONICS SOCIETY, First page：2904, Last page：2910, 2014, [Reviewed]
  Zero-power control is applied to a double parallel magnetic suspension system with mixed polarity. The most basic magnetic suspension system consists of a suspended object (floator), an electromagnet and a power amplifier. In double parallel magnetic suspension, two floators and electromagnets are controlled with a single power amplifier. The feasibility of the zero-power control in double parallel magnetic suspension with mixed polarity is discussed. It is analytically shown that the condition for the system with a zero-power controller to be controllable is independent of the polarity. It is confirmed experimentally that the zero-power suspension is achieved in both uniform-polarity and mixed-polarity suspension systems.
  IEEE, English, International conference proceedings
  ISSN：1553-572X, Web of Science ID：WOS:000389471602120
• Zero‐power control of double parallel magnetic suspension system with parallel connected coils　　　　　　　　　　　　　　　
  成澤慶宜; 水野毅; 高崎正也; 石野裕二
  日本機械学会論文集(Web), Volume：80, Number：813, First page：DR0126 (WEB ONLY), Last page：DR0126, 2014, [Reviewed]
  Parallel magnetic suspension has been proposed where multiple floators are controlled with a single power amplifier. The feasibility of voltage-controlled double parallel magnetic suspension with parallel connected coils has been already demonstrated in the previous work. This study focuses on the zero-power control in a voltage-controlled double parallel suspension system with parallel connected coils. In this system, there are three methods of achieving zero-power control: feeding back the control voltage, either or the sum of the coil currents. This paper shows the conditions for the system with each zero-power controller to be controllable, and compares their performances.
  一般社団法人 日本機械学会, Japanese
  DOI：https://doi.org/10.1299/transjsme.2014dr0126
  DOI ID：10.1299/transjsme.2014dr0126, ISSN：2187-9761, J-Global ID：201402283969546713, CiNii Articles ID：130004728612
• Force measurement using double series magnetic suspension　　　　　　　　　　　　　　　
  水野毅; 関根大輔; 高崎正也; 石野裕二
  日本機械学会論文集(Web), Volume：80, Number：814, First page：DR0163 (WEB ONLY), Last page：DR0163, 2014, [Reviewed]
  Double Series magnetic suspension is applied to force measurement. In a double series magnetic suspension system, two floators are suspended with a single electromagnet. The attractive force of the electromagnet directly acts on the first (upper) floator in which a permanent magnet is installed. The motion of the second (lower) floator is controlled indirectly through the attractive force of the permanent magnet. When PID control is applied to the second floator, the first floator displaces proportionally to external force acting on the second floator. Therefore, the force can be estimated for the displacement of the first floator. When the parameters are set appropriately, even small force leads to large displacement so that the proposed measurement method is suitable for noncontact measurement of micro force. An apparatus was fabricated for experimental study on the proposed measurement method. Its effectiveness was demonstrated experimentally.
  一般社団法人 日本機械学会, Japanese
  DOI：https://doi.org/10.1299/transjsme.2014dr0163
  DOI ID：10.1299/transjsme.2014dr0163, ISSN：2187-9761, J-Global ID：201402242460282891, CiNii Articles ID：130005004870
• Applicability of zero-power control to flux-path control magnetic suspension system　　　　　　　　　　　　　　　
  Takeshi Mizuno; Masaya Takasaki; Yuji Ishino
  Proceedings of the SICE Annual Conference, First page：2610, Last page：2612, 2013
  The necessary conditions under which zero-power control is achievable in the flux-path control magnetic suspension system were clarified in a general form. A basic model of the flux-path control magnetic suspension was derived. The controllability of the suspension system including a zero-power controller is studied analytically on a basis of the derived model. The analytical study shows that nonzero stiffness in a flux-path control module is necessary for the controllability in addition to nonzero stiffness in the suspension system.
  Society of Instrument and Control Engineers (SICE), English, International conference proceedings
  SCOPUS ID：84888615510
• Fabrication of Power Saving Solar Magnetic Suspension System　　　　　　　　　　　　　　　
  ISHINO Yuji; MIZUNO Takeshi; TAKASAKI Masaya
  JSDD, Volume：7, Number：4, First page：528, Last page：538, 2013
  Extra low-power magnetic suspension system is achieved using solely solar power. Presently, solar cells have become more efficient and cost-saving year by year. In this work, a solar power generation technique is combined with zero-power control magnetic suspension. The zero-power control is achieved by converging the control current to zero in the steady states where the bias force generated by a permanent magnet is balanced with the gravitational force. Therefore, the steady-states power consumption becomes virtually zero in this suspension system. However, peripheral devices including sensors and controllers need power in both transient and steady states. Hence, the power consumed in the peripheral devices becomes dominant. In this work, dedicated power-saving peripheral devices are fabricated. It is observed that the average power consumed by the electromagnet is 20[mW] for suspending a 90-gram mass, and the power consumed by the peripheral devices is 13[mW]. In contrast, a conventional system consumes a few watts to suspend a floator of the same dimensions. The solar cells used in the apparatus has a maximum power capacity of 2[W] under a typical summer sunlight (approximately 120[klx]). The fabricated system can achieve stable suspension even under a illuminance of a fluorescent lamp of 5[klx].
  The Japan Society of Mechanical Engineers, English
  DOI：https://doi.org/10.1299/jsdd.7.528
  DOI ID：10.1299/jsdd.7.528, ISSN：1881-3046, CiNii Articles ID：130003384436
• Excitation of Surface Acoustic Wave Using Frequency Selectivity　　　　　　　　　　　　　　　
  Uchiage Kota; Saito Kei; Takasaki Masaya; Mizuno Takeshi
  Proceedings of JSPE Semestrial Meeting, Volume：2013, First page：173, Last page：174, 2013
  弾性表面波リニアモータに使用するステータ振動子の大面積化のために圧電材料と非圧電材料を組み合わせる間接励振という方法を用いる．複数の振動子で励振させた場合，スライダを駆動するのが困難な範囲が存在する．従来よりも交差指幅の広い振動子を用いたが，弾性表面波の励振部より波を一様かつ広範囲に励振すると効率が低下する問題がある．本研究では駆動周波数の調整によって励振範囲を選択し，効率の改善を目指す．
  The Japan Society for Precision Engineering, Japanese
  DOI：https://doi.org/10.11522/pscjspe.2013A.0.173.0
  DOI ID：10.11522/pscjspe.2013A.0.173.0, CiNii Articles ID：130004661084
• Pressure Distribution Measurement for the Gap of Ultrasonic Suspension:Development of pressure sensor　　　　　　　　　　　　　　　
  Chida Ryutaro; Ishino Yuji; Takasaki Masaya; Mizuno Takashi
  Proceedings of JSPE Semestrial Meeting, Volume：2013, First page：143, Last page：144, 2013
  超音波振動子の振動面近傍で板状物体が浮揚する近距離場音波浮揚現象において鉛直下向きで物体が非接触支持される現象は超音波支持と呼ばれる．本報ではこの現象の詳細を把握するため，振動面の圧力を直接測定可能なセンサを製作し，ギャップにおける圧力分布測定を行った．また，その結果を先行研究において計測した作用力特性と比較し，同様の傾向が見られることを確認した．
  The Japan Society for Precision Engineering, Japanese
  DOI：https://doi.org/10.11522/pscjspe.2013A.0.143.0
  DOI ID：10.11522/pscjspe.2013A.0.143.0, CiNii Articles ID：130004661067
• Development of flux-path control magnetic suspension system using flux concentration　　　　　　　　　　　　　　　
  Atsushi Takabayshi; Takeshi Mizuno; Masaya Takasaki; Yuji Ishino
  Nihon Kikai Gakkai Ronbunshu, C Hen/Transactions of the Japan Society of Mechanical Engineers, Part C, Volume：79, Number：801, First page：1483, Last page：1494, 2013, [Reviewed]
  Flux-path control magnetic suspension using flux concentration is proposed and studied both analytically and experimentally. The proposed system used control plates made of permanent magnet instead of ferromagnetic material. It was shown that flux-concentrated type can produce larger suspension force than the conventional flux-interrupted type. However, it was difficult to achieve stable suspension since the control (variable) force was not so large. In this paper, to solve such a problem, the characteristics of the suspension system are studied by finite element analysis. The effects of the direction of motion, the operating positions and the shape of the control plates are investigated. An experimental apparatus with a variable flux-path unit using flux concentration is developed based on the analytical result. A single-axis stable suspension is achieved by applying PD control in the developed apparatus. © 2013 The Japan Society of Mechanical Engineers.
  Japanese, Scientific journal
  DOI：https://doi.org/10.1299/kikaic.79.1483
  DOI ID：10.1299/kikaic.79.1483, ISSN：0387-5024, SCOPUS ID：84879981205
• Multiple Magnetic Suspension Systems:(1st report: Basic Concepts and Theorems)　　　　　　　　　　　　　　　
  MIZUNO Takeshi; TAKASAKI Masaya; ISHINO Yuji
  Journal of System Design and Dynamics, Volume：7, Number：2, First page：242, Last page：253, 2013, [Reviewed]
  The paper proposes multiple magnetic suspension systems. The concepts are presented by using their basic models. They are classified according to multiple structure, power amplifier and coil connection. According to the first item, they can be divided into series and parallel. This paper mainly treats the latter. The controllability and the observability of each parallel suspension system are discussed based on its mathematical model. The concept of self-sensing magnetic suspension is stretched to the multiple systems. The feasibility of parallel magnetic suspension is demonstrated by simulation
  一般社団法人 日本機械学会, English
  CiNii Articles ID：130003368522
• Fabrication of Power Saving Solar Magnetic Suspension Systems　　　　　　　　　　　　　　　
  ISHINO Yuji; MIZUNO Takeshi; TAKASAKI Masaya
  TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series C, Volume：79, Number：800, First page：1056, Last page：1065, 2013, [Reviewed]
  Extra low-power suspension in the gravitational field of ground is achieved by a magnetic suspension system whose power source is solely a solar generator. Presently, solar cells become more efficient and cost-saving year by year. In this study, photovoltaic power generation technique is combined with the zero-power magnetic suspension. The zero-power control achieves the steady state in which the attractive force produced by a permanent magnets balances the weight of the floator and the control current converges to zero. Therefore, the power consumed for suspension is very small. However, the peripheral devices including sensors and a controller need power for their operations. The consumption power in the peripheral devices becomes dominant in the total power in the steady state. In this work, dedicated power-saving peripheral devices are newly fabricated. The average consumption power in the electromagnet is 20mW to suspend a 90-gram mass, while the consumption power in the peripheral devices is 13mW. The photovoltaic cells used in the apparatus has a maximum power capacity of almost 2W in the summer sunlight of 120klx. The system achieves stable suspension even under the illuminance of a fluorescent lamp of 5klx in the standalone.
  一般社団法人 日本機械学会, Japanese
  ISSN：0387-5024, CiNii Articles ID：130003374984
• Fabrication of Power Saving Solar Magnetic Suspension System　　　　　　　　　　　　　　　
  石野裕二; 水野毅; 高崎正也
  日本機械学会論文集 C編(Web), Volume：79, Number：800, First page：1056-1065 (WEB ONLY), Last page：538, 2013, [Reviewed]
  Extra low-power magnetic suspension system is achieved using solely solar power. Presently, solar cells have become more efficient and cost-saving year by year. In this work, a solar power generation technique is combined with zero-power control magnetic suspension. The zero-power control is achieved by converging the control current to zero in the steady states where the bias force generated by a permanent magnet is balanced with the gravitational force. Therefore, the steady-states power consumption becomes virtually zero in this suspension system. However, peripheral devices including sensors and controllers need power in both transient and steady states. Hence, the power consumed in the peripheral devices becomes dominant. In this work, dedicated power-saving peripheral devices are fabricated. It is observed that the average power consumed by the electromagnet is 20[mW] for suspending a 90-gram mass, and the power consumed by the peripheral devices is 13[mW]. In contrast, a conventional system consumes a few watts to suspend a floator of the same dimensions. The solar cells used in the apparatus has a maximum power capacity of 2[W] under a typical summer sunlight (approximately 120[klx]). The fabricated system can achieve stable suspension even under a illuminance of a fluorescent lamp of 5[klx].
  一般社団法人 日本機械学会, Japanese
  DOI：https://doi.org/10.1299/kikaic.79.1056
  DOI ID：10.1299/kikaic.79.1056, ISSN：1884-8354, J-Global ID：201302269684853914, CiNii Articles ID：130003384436
• Development of Flux‐Path Control Magnetic Suspension System Using Flux Concentration　　　　　　　　　　　　　　　
  高林篤; 水野毅; 高崎正也; 石野裕二
  日本機械学会論文集 C編(Web), Volume：79, Number：801, First page：1483-1494 (WEB ONLY), Last page：1494, 2013, [Reviewed]
  Flux-path control magnetic suspension using flux concentration is proposed and studied both analytically and experimentally. The proposed system used control plates made of permanent magnet instead of ferromagnetic material. It was shown that flux-concentrated type can produce larger suspension force than the conventional flux-interrupted type. However, it was difficult to achieve stable suspension since the control (variable) force was not so large. In this paper, to solve such a problem, the characteristics of the suspension system are studied by finite element analysis. The effects of the direction of motion, the operating positions and the shape of the control plates are investigated. An experimental apparatus with a variable flux-path unit using flux concentration is developed based on the analytical result. A single-axis stable suspension is achieved by applying PD control in the developed apparatus.
  一般社団法人 日本機械学会, Japanese
  DOI：https://doi.org/10.1299/kikaic.79.1483
  DOI ID：10.1299/kikaic.79.1483, ISSN：1884-8354, J-Global ID：201302256493369350, CiNii Articles ID：130003375033
• Double Electrostatic Suspension System Using Variable Capacitor　　　　　　　　　　　　　　　
  KATO Takaaki; MIZUNO Takeshi; ISHINO Yuji; TAKASAKI Masaya
  Journal of System Design and Dynamics, Volume：20, Number：4, First page：675, Last page：682, Dec. 2012, [Reviewed]
  Voltage control using a variable capacitor and floator position estimation are proposed for designing a low-cost electrostatic suspension control system. When an electrostatic actuator and a variable capacitor are connected in series to a constant power supply, the voltage applied to the suspension system can be changed by varying the capacitance of the variable capacitor because the electrostatic suspension system can be treated as a capacitor. Moreover, the voltage is determined by these capacitances and so the floator position can be estimated from the voltage applied to the suspension system and the capacitance of the variable capacitor. The proposed voltage control system enables electrostatic suspension without a high-voltage amplifier or direct floator position detection. Therefore, this control system can reduce the total cost of electrostatic suspension systems. The principle of the proposed self-sensing control is described using a basic electrostatic suspension model. The position of the floator was estimated according to this principle. Self-sensing suspension was achieved by feeding back the estimated signal.
  一般社団法人 日本機械学会, English
  ISSN：0919-4452, CiNii Articles ID：110009594549
• A modified zero-power control and its application to vibration isolation system　　　　　　　　　　　　　　　
  Md Emdadul Hoque; Takeshi Mizuno; Yuji Ishino; Masaya Takasaki
  JOURNAL OF VIBRATION AND CONTROL, Volume：18, Number：12, First page：1788, Last page：1797, Oct. 2012, [Reviewed]
  In this paper we present an improved zero-power controlled magnetic suspension system that has the capability to adjust stiffness. The conventional zero-power control system produces constant negative stiffness, and the stiffness solely depends on the capacity of the permanent magnets or the gap-force coefficient of the magnets. This becomes an obstacle to the fields of application of zero-power control where the adjustment of stiffness is necessary, such as developing a vibration isolation system. In this research, the basic zero-power control system is modified such that it can adjust stiffness by adding a minor proportional feedback of displacement to the zero-power controller. Finally, a vibration isolation system is developed by combining a positive stiffness spring in series with a negative stiffness suspension realized by the modified zero-power controller. The proposed control system and the developed vibration isolation system are investigated both analytically and experimentally.
  SAGE PUBLICATIONS LTD, English, Scientific journal
  DOI：https://doi.org/10.1177/1077546311419985
  DOI ID：10.1177/1077546311419985, ISSN：1077-5463, eISSN：1741-2986, Web of Science ID：WOS:000309354300004
• Improvement of Transient Characteristics of Negative Stiffness Control System by Feedforward Control　　　　　　　　　　　　　　　
  SHAHADAT Mhia M. Z; MIZUNO Takeshi; ISHINO Yuji; TAKASAKI Masaya
  日本AEM学会誌 = Journal of the Japan Society of Applied Electromagnetics, Volume：20, Number：3, First page：619, Last page：625, Sep. 2012, [Reviewed]
  日本AEM学会, English
  ISSN：0919-4452, CiNii Articles ID：110009544612
• Application of Unbalance Compensation to Totally Active Magnetically Suspended Gyro　　　　　　　　　　　　　　　
  OBARA Kyosuke; MIZUNO Takeshi; ISHINO Yuji; TAKASAKI Masaya
  日本AEM学会誌 = Journal of the Japan Society of Applied Electromagnetics, Volume：20, Number：2, First page：446, Last page：452, Jun. 2012, [Reviewed]
  日本AEM学会, English
  ISSN：0919-4452, CiNii Articles ID：110009490214
• Realization of Voltage-controlled Double Parallel Magnetic Suspension System　　　　　　　　　　　　　　　
  NISHIMURA Kazuya; MIZUNO Takeshi; TAKASAKI Masaya; ISHINO Yuji
  日本AEM学会誌 = Journal of the Japan Society of Applied Electromagnetics, Volume：20, Number：2, First page：342, Last page：348, Jun. 2012, [Reviewed]
  日本AEM学会, English
  ISSN：0919-4452, CiNii Articles ID：110009490197
• 微小物体を対象とした非接触超音波支持の作用力特性―第1報 作用力測定機構の製作及び作用力特性の取得―　　　　　　　　　　　　　　　
  千野翔太; 加藤裕弘; 石野裕二; 高崎正也; 水野毅
  精密工学会誌, Volume：78, Number：4, First page：332, Last page：337, Apr. 2012
  Japanese
  DOI：https://doi.org/10.2493/jjspe.78.332
  DOI ID：10.2493/jjspe.78.332, ISSN：0912-0289, J-Global ID：201202237642736873
• Development of Flux‐Path Control Module with a Single Actuator　　　　　　　　　　　　　　　
  水野毅; 酒井康博; 高崎正也; 石野裕二
  日本AEM学会誌, Volume：20, Number：1, First page：294, Last page：299, Mar. 2012, [Reviewed]
  日本AEM学会, Japanese
  ISSN：0919-4452, J-Global ID：201202272639181372, CiNii Articles ID：110009437794
• Acting Force Characteristics of Non-contact Ultrasonic Support Mechanism for Minute Object:4th report: Influence of object features　　　　　　　　　　　　　　　
  Chino Shota; Takasaki Masaya; Ishino Yuji; Mizuno Takeshi
  Proceedings of JSPE Semestrial Meeting, Volume：2012, First page：121, Last page：122, 2012
  超音波振動子の振動面近傍で板状物体が浮揚する近距離場音波浮揚現象において鉛直下向きでの物体の非接触支持が可能であり、振動面中心へ物体を引き込む水平方向復元力が作用することが確認されている。本報では対象物の形状（表面粗さ及び厚さ）が吸引力特性に及ぼす影響を実験的に調べた．
  The Japan Society for Precision Engineering, Japanese
  DOI：https://doi.org/10.11522/pscjspe.2012A.0.121.0
  DOI ID：10.11522/pscjspe.2012A.0.121.0, CiNii Articles ID：130004660558
• Ultrasonic Dewatering in Minute Holes (1st Report):—Observation of Dewatering Phenomenon—　　　　　　　　　　　　　　　
  高崎 正也; 遠藤 崇訓; 水野 毅
  Journal of the Japan Society for Precision Engineering, Volume：78, Number：4, First page：338, Last page：342, 2012
  Printed-circuit boards are widely used for miniaturizing electronic equipments. According to the demand, diameter of holes in the boards is decreasing. There is a problem in their fabrication processes, in which they should be cleaned in water. After the cleaning process, water remains in the small holes. The remained water contains chemical material and/or dusts and might cause damage of the boards in the future. Conventionally, air pressure has been used to remove the water in the boards. But the method is not valid for holes that have bottoms inside neither for much smaller holes. Heating could be an alternative method, but this method might leave chemical material in the water and cause deflection of the board. In this research, a new dewatering method has been proposed. The method utilizes standing wave of ultrasonic wave in air. An experimental apparatus was organized to observe the ultrasonic dewatering and consisted of an ultrasonic transducer and a reflector. Proposed dewatering was observed successfully. The sound pressure in the standing wave was measured by a microphone. A condition for successful dewatering was discussed with reference to the distribution of the sound pressure.
  The Japan Society for Precision Engineering, Japanese
  DOI：https://doi.org/10.2493/jjspe.78.338
  DOI ID：10.2493/jjspe.78.338, ISSN：0912-0289, CiNii Articles ID：130002122224
• Self-Sensing Control of Electrostatic Suspension Using Variable Capacitor　　　　　　　　　　　　　　　
  Takaaki KATO; Takeshi MIZUNO; Yuji ISHINO; Masaya TAKASAKI
  Journal of System Design and Dynamics, Volume：6, Number：5, First page：729, Last page：739, 2012
  Japan Society of Mechanical Engineers, Scientific journal
  DOI：https://doi.org/10.1299/jsdd.6.729
  DOI ID：10.1299/jsdd.6.729, eISSN：1881-3046
• Damping-insensitive mass measurement using a damped dynamic vibration absorber　　　　　　　　　　　　　　　
  Takeshi Mizuno; Satoru Yamamoto; Yuji Ishino; Masaya Takasaki
  ASME 2012 5th Annual Dynamic Systems and Control Conference Joint with the JSME 2012 11th Motion and Vibration Conference, DSCC 2012-MOVIC 2012, Volume：3, First page：857, Last page：862, 2012, [Reviewed]
  A new mass measurement using a damped dynamic vibration absorber is developed. A mass-spring system with a dynamic vibration absorber has a fixed point through which all the frequency response curves pass independently of damping in the absorber. The proposed method of measurement utilizes this fixed point to estimate mass independently of damping in the absorber. The principle of measurement was described based on a mathematical model. An experimental apparatus based on the principles was fabricated. Mass measurement was carried out with the apparatus. The measurement results demonstrated the efficacy of the proposed method. Copyright © 2012 by ASME.
  English, International conference proceedings
  DOI：https://doi.org/10.1115/DSCC2012-MOVIC2012-8823
  DOI ID：10.1115/DSCC2012-MOVIC2012-8823, SCOPUS ID：84885945144
• Proposal of force measurement using series magnetic suspension　　　　　　　　　　　　　　　
  Takeshi Mizuno; Daisuke Sekine; Yuji Ishino; Masaya Takasaki
  ASME 2012 5th Annual Dynamic Systems and Control Conference Joint with the JSME 2012 11th Motion and Vibration Conference, DSCC 2012-MOVIC 2012, Volume：2, First page：55, Last page：60, 2012, [Reviewed]
  Series magnetic suspension is applied to force measurement. In a double series magnetic suspension system, two floators are suspended with a single electromagnet. The attractive force of the electromagnet directly acts on the first floator in which a permanent magnet is installed. The motion of the second floator is controlled indirectly through the attractive force of the permanent magnet. When PID control is applied to the second floator, the first floator displaces proportionally with the external force acting on the second floator even though the second floator does not move in the steady state. Therefore, the force can be estimated for the displacement of the first floator. When the stiffness between the first and second floators is low, even small force leads to large displacement so that the proposed measurement method is suitable for noncontact measurement of micro force. An apparatus was fabricated for experimental study on the proposed measurement method. Its effectiveness was demonstrated experimentally. Copyright © 2012 by ASME.
  English, International conference proceedings
  DOI：https://doi.org/10.1115/DSCC2012-MOVIC2012-8560
  DOI ID：10.1115/DSCC2012-MOVIC2012-8560, SCOPUS ID：84885913527
• Study on double parallel magnetic suspension system with parallel connection　　　　　　　　　　　　　　　
  Takeshi Mizuno; Kazuya Nishimura; Yuji Ishino; Masaya Takasaki
  ASME 2012 5th Annual Dynamic Systems and Control Conference Joint with the JSME 2012 11th Motion and Vibration Conference, DSCC 2012-MOVIC 2012, Volume：2, First page：67, Last page：72, 2012, [Reviewed]
  A double parallel magnetic suspension with parallel connection is achieved. In the double parallel magnetic suspension system, two magnetic suspension subsystems are controlled with a single power amplifier. Double parallel suspension systems are classified into two types based on the connection of the two coils: series-connected and parallelconnected. The feasibility of series-connected magnetic suspension has been already demonstrated in the previous works. This paper focuses on the parallel-connected parallel suspension. The controllability of the parallel-connected parallel suspension is discussed based on a mathematical model. The feasibility of parallel-connected magnetic suspension is demonstrated experimentally. Copyright © 2012 by ASME.
  English, International conference proceedings
  DOI：https://doi.org/10.1115/DSCC2012-MOVIC2012-8812
  DOI ID：10.1115/DSCC2012-MOVIC2012-8812, SCOPUS ID：84885898118
• Cost-effective implementation of acceleration feedback to vibration isolation system using negative stiffness　　　　　　　　　　　　　　　
  Mhia Md. Zaglul Shahadat; Takeshi Mizuno; Yuji Ishino; Masaya Takasaki
  ASME 2012 5th Annual Dynamic Systems and Control Conference Joint with the JSME 2012 11th Motion and Vibration Conference, DSCC 2012-MOVIC 2012, Volume：3, First page：793, Last page：801, 2012, [Reviewed]
  A horizontal vibration isolation system using negative stiffness control technique is realized. The developed vibration isolation system consists of isolation table and middle table. In negative stiffness control technique, the isolation table is driven by negative stiffness controlled actuator and the middle table is driven by positive stiffness controlled actuator. The vibration isolation system with negative stiffness control can suppress ground vibration and low frequency sinusoidal direct disturbance sufficiently. However in present time accuracy requirement in Hitech manufacturing process has turned into nanometer range. Thus for further improvement in dynamic performance of the developed system, the acceleration feedback is added with negative stiffness control technique. However commercial servotype accelerometer is expensive and makes the system costlier. In this research MEMS (circuit) accelerometer is used since it is cost effective. Experiments are conducted with both servo and MEMS accelerometers individually and results are compared. From experimental results it has been apparent that servo-type accelerometer can be replaced with MEMS accelerometer for such developed system. Copyright © 2012 by ASME.
  English, International conference proceedings
  DOI：https://doi.org/10.1115/DSCC2012-MOVIC2012-8639
  DOI ID：10.1115/DSCC2012-MOVIC2012-8639, SCOPUS ID：84885895180
• Study on the observability of double parallel magnetic suspension systems　　　　　　　　　　　　　　　
  Takeshi Mizuno; Yuji Ishino; Masaya Takasaki
  IECON Proceedings (Industrial Electronics Conference), First page：2793, Last page：2797, 2012, [Reviewed]
  The observability of parallel suspension is discussed based on mathematical models. The treated parallel suspension systems use a voltage-output power amplifier for energizing the multiple electromagnets. They are classified to series-connected and parallel-connected according to the connection of the coils of the electromagnets. The condition for each system to be observable is presented analytically. The analyses clarify that the condition of observability is same as that of controllability in the series-connected parallel magnetic suspension system with the coil current sensed solely. Such equivalence is also found for the parallel-connected suspension system with the sum of the coil currents sensed. © 2012 IEEE.
  English, International conference proceedings
  DOI：https://doi.org/10.1109/IECON.2012.6389135
  DOI ID：10.1109/IECON.2012.6389135, SCOPUS ID：84872910238
• Sheet-like Ultrasonic Transducer for Tactile Display Application　　　　　　　　　　　　　　　
  Masaya Takasaki; Michihiro Suzaki; Takeshi Mizuno
  INTERNATIONAL CONGRESS ON ULTRASONICS (GDANSK 2011), Volume：1433, First page：701, Last page：704, 2012, [Reviewed]
  A sheet-like ultrasonic transducer (SUT) was proposed to realize tactile feedback on a touchscreen. Exciting normal vibration on the SUT surface, basic principle of surface acoustic wave can be applied. Prototype of the SUT was fabricated using silica glass substrate whose dimension was 60 x 60 x 0.3 mm(3) and a LiNbO3 piece with an interdigital transducer. To show feasibility of SUT application for the tactile feedback, friction between the SUT and a slider, which is installed on operator's fingertip, was measured. The friction was reduced by ultrasonic vibration of the SUT. The prototype SUT was installed on a touchscreen and controlled to indicate roughness. Under the control, roughness sensation was experienced successfully. Additionally, a larger SUT was fabricated and tested.
  AMER INST PHYSICS, English, International conference proceedings
  DOI：https://doi.org/10.1063/1.3703279
  DOI ID：10.1063/1.3703279, ISSN：0094-243X, Web of Science ID：WOS:000307631000150
• Actuation Force Measurement Mechanism for Non-contact Ultrasonic Suspension　　　　　　　　　　　　　　　
  Masaya Takasaki; Shota Chino; Yasuhiro Kato; Yuji Ishino; Takeshi Mizuno
  EMERGING TECHNOLOGY IN PRECISION ENGINEERING XIV, Volume：523-524, First page：727, Last page：732, 2012, [Reviewed]
  In near-field levitation, an object can be levitated vertically upward above vibrating surface of an ultrasonic transducer. En this case, a repulsive force acts on the object. On the other hand, it has been reported that a minute object can be suspended vertically downward under the vibrating surface with a small gap in the air. We call this phenomenon ultrasonic suspension. Under the suspension, an attractive force acts on the object. When an object is suspended, there is restoring force, which pulls the object to the center of the vibrating surface. Our aim is to characterize the actuation forces under the suspension. Simultaneous measurement of vertical and horizontal actuation forces is required. A servo type measuring mechanism was proposed. A 1 DOF mechanism with a cantilever and a voice coil motor (VCM) was fabricated as a prototype. The prototype was calibrated and utilized for measurement of vertical actuation force. The result showed enough accuracy and repeatability. Then, a 2 DOF actuation force measurement mechanism was fabricated. The mechanism was consisted of a base to fix the object and two thin wires to support the base. Position of the base was controlled by three VCMs based on PID control. The ultrasonic suspension actuation forces were characterized successfully.
  TRANSACTION PUBLISHERS, English, International conference proceedings
  DOI：https://doi.org/10.4028/www.scientific.net/KEM.523-524.727
  DOI ID：10.4028/www.scientific.net/KEM.523-524.727, ISSN：1013-9826, Web of Science ID：WOS:000310865600126
• Mass Measurement Using the Fixed Point of a Spring-Mass System with a Dynamic Vibration Absorber　　　　　　　　　　　　　　　
  YAMAMOTO Satoru; ISHINO Yuji; TAKASAKI Masaya; MIZUNO Takeshi
  Journal of System Design and Dynamics, Volume：6, Number：3, First page：241, Last page：250, 2012, [Reviewed]
  A vibration-type measurement system characterized by the use of an undamped dynamic vibration absorber has been developed. However, inevitable damping in the absorber may cause measurement error. A new method of measuring mass is proposed to overcome this problem. The measurement system utilizes the fixed point of a mass-spring system with a dynamic vibration absorber so that the mass is estimated regardless of damping in the absorber. A phase-looked loop (PLL) is used to achieve tuning. The principle of measurement is described on the basis of a mathematical model. A measuring apparatus was designed and fabricated, and several of its basic characteristics were studied experimentally. Damping of the primary system was found to affect fixed point formation. By reducing the damping of the primary system by a voice coil motor, the measurement conditions were achieved. The efficacy of the apparatus was studied both analytically and experimentally. The measurement conditions were realized automatically by the PLL. Mass measurement was performed while the PLL was operated; the average measurement error was within 0.21 [%].
  一般社団法人 日本機械学会, English
  CiNii Articles ID：130002100210
• Double Electrostatic Suspension System　　　　　　　　　　　　　　　
  KATO Takaaki; MIZUNO Takeshi; ISHINO Yuji; TAKASAKI Masaya
  Journal of System Design and Dynamics, Volume：6, Number：5, First page：700, Last page：712, 2012, [Reviewed]
  Multiple electrostatic suspension suspends multiple floators with a single power amplifier. The controllability of double parallel suspension was previously analyzed and the conditions to be controllable were shown. To ensure the analytical results, single-DOF suspension systems were fabricated, and a double parallel electrostatic suspension system consisted of these systems. The feasibility of double parallel electrostatic suspension was demonstrated experimentally. Dynamic characteristics of double parallel electrostatic suspension were studied based on step responses and frequency responses.
  一般社団法人 日本機械学会, English
  CiNii Articles ID：130003368502
• A three-axis vibration isolation system using modified zero-power controller with parallel mechanism technique　　　　　　　　　　　　　　　
  Md. Emdadul Hoque; Takeshi Mizuno; Yuji Ishino; Masaya Takasaki
  MECHATRONICS, Volume：21, Number：6, First page：1055, Last page：1062, Sep. 2011, [Reviewed]
  This paper proposes a module-type three-degree-of-freedom vibration isolation system using modified zero-power control. Three vibration isolation modules are connected together using parallel mechanism to control 3-DOF motions. Each module consists of a common base, an individual middle mass and a common isolation table. The base to the middle mass is suspended by positive springs generated by active and passive system, and the middle mass and the isolation table is connected by negative spring realized by active-type modified zero-power control. The developed system could realize zero-compliance to direct disturbances as well as good ground vibration isolation. Furthermore, the isolation table is supported by a weight support mechanism for supporting heavy payloads. In the previous research, a concentrated middle mass with redundant actuators, in the vertical and horizontal directions, were used. Therefore, a vibration isolation system is proposed in this work using modular concept to overcome those drawbacks. Each module is controlled separately by decentralized control technique, and three modules can be used for three-degree-of-freedom of motion control. Therefore, no redundancy of actuator is occurred. Moreover, an improved zero-power controller is presented that can adjust negative stiffness instead of conventional zero-power controller. The results obtained from analytical and experimental studies show that the modular technique is reliable and efficient approach to vibration control, and represents a suitable alternative to the conventional active vibration isolation systems. (C) 2011 Elsevier Ltd. All rights reserved.
  PERGAMON-ELSEVIER SCIENCE LTD, English, Scientific journal
  DOI：https://doi.org/10.1016/j.mechatronics.2011.05.002
  DOI ID：10.1016/j.mechatronics.2011.05.002, ISSN：0957-4158, Web of Science ID：WOS:000295664900016
• Multiple magnetic suspension systems (2nd eport: Realization of double parallel magnetic suspension)　　　　　　　　　　　　　　　
  Takumi Sakurada; Takeshi Mizuno; Masaya Takasaki; Yuji Ishino
  Nihon Kikai Gakkai Ronbunshu, C Hen/Transactions of the Japan Society of Mechanical Engineers, Part C, Volume：77, Number：779, First page：2684, Last page：2694, 2011
  The feasibility of parallel magnetic suspension is studied experimentally. Parallel magnetic suspension suspends multiple floators with a single power amplifier. Parallel magnetic suspension systems are classified according to the number of floators (multiplicity) , the output type of amplifier and the connection method of coils. This paper focuses on the current-controlled double suspension system with series connected coils. An experimental system is built by combining two magnetic suspension systems. A simultaneous stable levitation of the two floators was achieved by using PD control with a single power amplifier. Several dynamics characteristics were measured. They agreed with simulation results in tendency. © 2011 The Japan Society of Mechanical Engineers.
  Japanese, Scientific journal
  ISSN：0387-5024, SCOPUS ID：84859572148
• 微小物体を対象とした非接触超音波支持の作用力測定:第３報 水平方向復元力の特性　　　　　　　　　　　　　　　
  千野 翔太; 加藤 裕弘; 石野 裕二; 高崎 正也; 水野 毅
  Volume：2011, First page：563, Last page：564, 2011
  超音波振動子の振動面近傍で板状物体が浮揚する近距離場音波浮揚現象において鉛直下向きでの物体の非接触支持が可能であり、振動面中心へ物体を引き込む水平方向復元力が作用することが確認されている。本報では振動面と対象物の中心間距離と復元力の関係を詳細に観測し，振動面振幅，振動面や対象物の面積などの条件によりその特性が変化するということを確認した．
  Japanese
  DOI：https://doi.org/10.11522/pscjspe.2011A.0.563.0
  DOI ID：10.11522/pscjspe.2011A.0.563.0, CiNii Articles ID：130004660303
• Controllability of parallel magnetic suspension system with mixed magnetic polarity　　　　　　　　　　　　　　　
  Takeshi Mizuno; Takumi Sakurada; Masaya Takasaki; Yuji Ishino
  IFAC Proceedings Volumes (IFAC-PapersOnline), Volume：18, Number：1, First page：956, Last page：961, 2011, [Reviewed]
  This paper studies the controllability of parallel magnetic suspension. The most basic magnetic suspension system consists of a suspended object (floator), an electromagnet and a power amplifier. In parallel magnetic suspension, multiple floators and electromagnets are controlled with a single power amplifier. The concept and the fundamental properties of parallel magnetic suspension systems have been already presented. They are classified according to the output of power amplifier and the connection of coils. However, the polarity of electromagnet has not been treated yet. In this work, the effect of the polarity is taken into consideration. It is shown that the controllability is independent of the polarity. © 2011 IFAC.
  English, International conference proceedings
  DOI：https://doi.org/10.3182/20110828-6-IT-1002.00988
  DOI ID：10.3182/20110828-6-IT-1002.00988, ISSN：1474-6670, SCOPUS ID：84866761379
• Analysis of Friction-Induced Oscillation in Negative Stiffness Control System　　　　　　　　　　　　　　　
  M. M. Zaglul Shahadat; Takeshi Mizuno; Yuji Ishino; Masaya Takasaki
  2011 50TH IEEE CONFERENCE ON DECISION AND CONTROL AND EUROPEAN CONTROL CONFERENCE (CDC-ECC), First page：952, Last page：957, 2011, [Reviewed]
  The effect of friction on a negative stiffness control system is investigated. The series combination of isolators of negative and positive stiffness of equal magnitude provides infinite stiffness as well as zero compliance of the vibration isolation table against direct static load. However the performance of negative stiffness control system is affected by friction adversely. In another word, nonlinear friction causes an adverse effect to the negative stiffness control system, such as limit cycle. In the present work, the friction induced limit cycle of the negative stiffness control system is identified by using describing function method. The intersection of linear and nonlinear part of the control system in the same complex plane reveals the existence of limit cycle which varies according to the control parameters. Hence the relationship between the stiffness of the negative stiffness control system and induced limit cycle (frequency and amplitude) is established theoretically. The induced limit cycle behavior is determined by the conditions of nonlinear part at the points of intersection. Finally the theoretical limit cycle for a specific set of control parameters in designing the controller is verified by experimental result under the same conditions.
  IEEE, English, International conference proceedings
  Web of Science ID：WOS:000303506201088
• Study on the Controllability of Double Parallel Magnetic Suspension System Considering Magnetic Polarity　　　　　　　　　　　　　　　
  Takeshi Mizuno; Yuji Ishino; Masaya Takasaki
  IECON 2011: 37TH ANNUAL CONFERENCE ON IEEE INDUSTRIAL ELECTRONICS SOCIETY, 2011, [Reviewed]
  The controllability of double parallel magnetic suspension system with hybrid magnet is studied analytically. The most basic magnetic suspension system consists of a suspended object (floator), an electromagnet and a power amplifier. In double parallel magnetic suspension, two floators and electromagnets are controlled with a single power amplifier. Parallel magnetic suspension systems are classified according to the output of power amplifier and the connection of coils. The controllability of each type system has been already studied. When hybrid magnets are used for suspension, however, another classification must be considered, which is magnetic polarity. This paper discuss the controllability of double parallel magnetic suspension with different polarities.
  IEEE, English, International conference proceedings
  ISSN：1553-572X, Web of Science ID：WOS:000299032400119
• Series-Type Multiple Magnetic Suspension System　　　　　　　　　　　　　　　
  MIZUNO Takeshi; MARUYAMA Yutaka; TAKASAKI Masaya; ISHINO Yuji; OSHIBA Yusuke
  Journal of System Design and Dynamics, Volume：5, Number：5, First page：1017, Last page：1029, 2011, [Reviewed]
  In series-type multiple magnetic suspension systems, multiple floators are suspended in tandem by one electromagnet. The nearest floator to the electromagnet is directly suspended by the electromagnet. The others are indirectly suspended by the attractive force due to the magnetization of the floators. The controllability and observability of series-type multiple magnetic suspension systems with an arbitrary number of floators are discussed. They are controllable and also observable even when only the displacement of the floator nearest to the electromagnet is detected. A series-type multiple magnetic suspension system was fabricated in order to verify the analyses experimentally. In the fabricated system, magnetic suspension units that are equipped with a sensor and an electromagnet are used instead of normal floators to carry out experiments in various conditions. As the first step to realize the levitation of multiple floators using one electromagnet and one sensor, a basic trial was carried out in the fabricated system.
  一般社団法人 日本機械学会, English
  CiNii Articles ID：130001014205
• Zero-Power Control of Parallel Magnetic Suspension Systems　　　　　　　　　　　　　　　
  MIZUNO Takeshi; SAKURADA Takumi; ISHINO Yuji; TAKASAKI Masaya
  Journal of System Design and Dynamics, Volume：5, Number：5, First page：765, Last page：776, 2011, [Reviewed]
  This paper discusses the feasibility of zero-power control in parallel magnetic suspension systems. In parallel magnetic suspension systems, multiple floators are suspend with a single power amplifier. The zero-power control has been used in magnetic suspension systems with permanent magnets providing bias flux. This control realizes the steady states where the attractive force produced by the permanent magnets balances the weight of the suspended object and the electromagnet coil current converges to zero. This paper shows that parallel magnetic suspension systems incorporating zero-power control can assign the poles arbitrary if the original parallel suspension systems are controllable. The feasibility of the zero-power control in a parallel magnetic suspension is demonstrated experimentally.
  一般社団法人 日本機械学会, English
  CiNii Articles ID：130001014186
• Application of Feedforward Control to A Vibration Isolation System Using Negative Stiffness Suspension　　　　　　　　　　　　　　　
  HOQUE Md. Emdadul; MIZUNO Takeshi; TAKASAKI Masaya; ISHINO Yuji
  Journal of System Design and Dynamics, Volume：5, Number：5, First page：777, Last page：788, 2011, [Reviewed]
  This paper presents a vibration isolation system using negative stiffness suspension. The vibration isolation system is developed by combining a positive stiffness suspension in series with a negative stiffness suspension. The developed system could realize zero-compliance to direct disturbance, as well as ground vibration isolation. In the previous system, the ground vibration and, the static and low frequency sinusoidal direct disturbances were efficiently suppressed. However, there was a reverse action in case of impulse or step wise disturbance. Therefore, a peak was appeared which was, sometimes, larger than the displacement caused by the step load. This unpleasant response might hamper the objective function of many advanced systems. In this research, a feedforward controller is added in combination with zero-power control to overcome this problem. Some experimental results are presented to verify the proposed control system in a vibration isolation apparatus.
  一般社団法人 日本機械学会, English
  CiNii Articles ID：130001014187
• Development of Three-Axis Active Vibration Isolator Using Displacement Cancellation Technique　　　　　　　　　　　　　　　
  SHAHADAT Mhia; Md. Zaglul; MIZUNO Takeshi; ISHINO Yuji; TAKASAKI Masaya
  Journal of System Design and Dynamics, Volume：5, Number：5, First page：1077, Last page：1093, 2011, [Reviewed]
  A three-degree-of-freedom (3-DOF) active vibration isolation system using displacement cancellation control technique is developed. The displacement cancellation concept is presented and implemented in this research to obtain zero compliance of vibration isolation table against direct static force as well as to suppress the dynamic disturbances acting on the isolation table. In the displacement cancellation control technique, relative movements of the vibration free table are followed with I-PD control and movements of the middle mass respect to base are controlled with PD control. The corresponding controllers are designed in such way so that actuator can generate opposite force against disturbance to cancel the effect of displacement of the middle mass on the vibration isolation table, which finally leads zero compliance of the isolation table. Voice coil motors (VCMs) are used for getting linear actuating effect and corresponding displacements of the table are detected by eddy-current gap sensors. The experimental results showed that the developed system with displacement cancellation mode control has capability to maintain zero compliance against direct static force in the 3-DOF motions associated with horizontal translations and a vertical rotation. Moreover experiments have been conducted to measure the dynamic responses of the vibration isolation table to direct disturbance.
  一般社団法人 日本機械学会, English
  CiNii Articles ID：130001014209
• Two-Axis Magnetic Suspension System with Dual Variable Flux-Path Units　　　　　　　　　　　　　　　
  NISHIMURA Kazuya; MIZUNO Takeshi; ISHINO Yuji; TAKASAKI Masaya; SAKAI Yasuhiro
  Journal of System Design and Dynamics, Volume：5, Number：6, First page：1226, Last page：1237, 2011, [Reviewed]
  A flux-path control magnetic suspension system with multiple magnetic sources is realized. The principle of the flux-path control magnetic suspension system is to control flux from a permanent magnet to the floator, and the attractive force acting on the floator by the motion control of control plates inserted between the permanent magnet and the floator. Stable suspension and 3-DOF control with a single magnetic source was achieved. However, the horizontal control force was much less than the vertical control force. Multiple magnetic source system can overcome such problem. A variable flux-path unit is developed for the realization of multiple magnetic source system. An experimental apparatus with two variable flux-path units is constructed. Stable levitation is achieved by applying PD and PID controls. In addition, stable levitation with zero-power control is also achieved.
  一般社団法人 日本機械学会, English
  CiNii Articles ID：130001164129
• Multiple Magnetic Suspension Systems (2nd Report: Realization of Double Parallel Magnetic Suspension)　　　　　　　　　　　　　　　
  櫻田巧; 水野毅; 高崎正也; 石野裕二
  日本機械学会論文集 C編(Web), Volume：77, Number：779, First page：2684-2694 (WEB ONLY), Last page：2694, 2011, [Reviewed]
  The feasibility of parallel magnetic suspension is studied experimentally. Parallel magnetic suspension suspends multiple floators with a single power amplifier. Parallel magnetic suspension systems are classified according to the number of floators (multiplicity) , the output type of amplifier and the connection method of coils. This paper focuses on the current-controlled double suspension system with series connected coils. An experimental system is built by combining two magnetic suspension systems. A simultaneous stable levitation of the two floators was achieved by using PD control with a single power amplifier. Several dynamics characteristics were measured. They agreed with simulation results in tendency.
  一般社団法人 日本機械学会, Japanese
  DOI：https://doi.org/10.1299/kikaic.77.2684
  DOI ID：10.1299/kikaic.77.2684, ISSN：1884-8354, J-Global ID：201102295422469176, CiNii Articles ID：130001055310
• Experimental Study on Microassembly by Using Liquid Surface Tension　　　　　　　　　　　　　　　
  KATO Yasuhiro; MIZUNO Takeshi; TAKAGI Hiroshi; ISHINO Yuji; TAKASAKI Masaya
  JCMSI : SICE journal of control, measurement, and system integration (SICE JCMSI), Volume：3, Number：5, First page：309, Last page：314, Sep. 2010, [Reviewed]
  English
  ISSN：1882-4889, CiNii Articles ID：10031140021
• Development of a flux-path control magnetic suspension system with swing-type control plates,Magnetic suspension system, Variable flux-path, Swing-type control plates, Zero-power control　　　　　　　　　　　　　　　
  Yasuhiro Sakai; Yuji Ishino; Masaya Takasaki; Takeshi Mizuno
  MOVIC 2010 - 10th International Conference on Motion and Vibration Control, Proceedings, Aug. 2010
  A new variable flux-path unit is developed for flux-path control magnetic suspension with multiple magnetic sources. The authors have proposed the variable flux-path magnetic suspension system as a unique magnetic suspension system using permanent magnet. This system has ferromagnetic plates between a permanent magnet and a floator. The flux from the permanent magnet to the floator, and the attractive force acting on the floator can be adjusted by the motion control of the control plates. Stable suspension and 2-DOF control with a single magnetic source was achieved. However, the horizontal control force was much less than the vertical control force. In this paper, flux-path control magnetic suspension with multiple magnetic sources is proposed. An experimental apparatus with a variable flux-path unit is developed for realizing multiple-magnetic-source systems. Basic characteristics of the apparatus are measured. Stable levitation is achieved by applying PD and PID controls. In addition, stable levitation with zero-power control is also achieved.
  Japan Society of Mechanical Engineers, English, International conference proceedings
  SCOPUS ID：85119102237
• A six-axis hybrid vibration isolation system using active zero-power control supported by passive weight support mechanism　　　　　　　　　　　　　　　
  Md Emdadul Hoque; Takeshi Mizuno; Yuji Ishino; Masaya Takasaki
  JOURNAL OF SOUND AND VIBRATION, Volume：329, Number：17, First page：3417, Last page：3430, Aug. 2010, [Reviewed]
  This paper presents a six-degree-of-freedom hybrid vibration isolation system integrated with an active negative suspension, an active-passive positive suspension and a passive weight support mechanism. The aim of the research consists in maximizing the system and control performances, and minimizing the system development and maintenance costs. The vibration isolation system is, fundamentally, developed by connecting an active negative suspension realized by zero-power control in series with an active-passive positive suspension. The system could effectively isolate ground vibrations in addition to suppress the effect of on-board generated direct disturbances of the six-axis motions, associated with vertical and horizontal directions. The system is further reinforced by introducing a passive weight support mechanism in parallel with the basic system. The modified system with zero-power control allows simplified design of the isolation table without power consumption. It also offers enhanced performance on direct disturbance suppression and large payload supporting capabilities, without degrading transmissibility characteristics. A mathematical model of the system is presented and, therefore, analyzed to demonstrate that zero-compliance to direct disturbance could be generated by the developed system. Experimental demonstrations validate the proposed concept that exhibits high stiffness of the isolation table to static and dynamic direct disturbances, and good transmissibility characteristics against ground vibration. Further improvements of the vibration isolation system and the control system are discussed as well. (C) 2010 Elsevier Ltd. All rights reserved.
  ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD, English, Scientific journal
  DOI：https://doi.org/10.1016/j.jsv.2010.03.003
  DOI ID：10.1016/j.jsv.2010.03.003, ISSN：0022-460X, eISSN：1095-8568, Web of Science ID：WOS:000278477000001
• Development of an Active Vibration Isolation System Using Linearized Zero-Power Control With Weight Support Springs　　　　　　　　　　　　　　　
  Md. Emdadul Hoque; Takeshi Mizuno; Daisuke Kishita; Masaya Takasaki; Yuji Ishino
  JOURNAL OF VIBRATION AND ACOUSTICS-TRANSACTIONS OF THE ASME, Volume：132, Number：4, Aug. 2010, [Reviewed]
  This paper presents a hybrid vibration isolation system using linearized zero-power control with weight support springs. The isolation system, fundamentally, is developed by linking a mechanical spring in series with a negative stiffness spring realized by zero-power control in order to insulate ground vibration as well as to reject the effect of on-board-generated direct disturbances. In the original system, the table is suspended from the middle table solely by the attractive force produced by the magnets and therefore, the maximum supporting force on the table is limited by the capacity of the permanent magnets used for zero-power control. To meet the growing demand to support heavy payload on the table, the physical model is extended by introducing an additional mechanism-weight support springs, in parallel with the above system. However, the nonlinearity of the zero-power control instigates a nonlinear vibration isolation system, which leads to a deviation from zero compliance to direct disturbance. Therefore, a nonlinear compensator for the zero-power control is employed furthermore to the system to meet the ever-increasing precise disturbance rejection requirements in the hi-technology systems. The fundamental characteristics of the system are explained analytically and the improved control performances are demonstrated experimentally. [DOI: 10.1115/1.4000968]
  ASME-AMER SOC MECHANICAL ENG, English, Scientific journal
  DOI：https://doi.org/10.1115/1.4000968
  DOI ID：10.1115/1.4000968, ISSN：1048-9002, Web of Science ID：WOS:000279993700006
• Development of 3‐DOF Active Control Type Magnetically Suspended Gyro　　　　　　　　　　　　　　　
  丸山裕; 水野毅; 高崎正也; 石野裕二
  日本機械学会論文集 C編, Volume：76, Number：766, First page：1445, Last page：1451, Jun. 2010, [Reviewed]
  Japanese
  DOI：https://doi.org/10.1299/kikaic.76.1445
  DOI ID：10.1299/kikaic.76.1445, ISSN：0387-5024, J-Global ID：201002289999377354
• Realization of a Zero-compliance System by Using Displacement Cancellation Control　　　　　　　　　　　　　　　
  Takeshi Mizuno; Takehiko Furushima; Yuji Ishino; Masaya Takasaki
  JOURNAL OF VIBRATION AND CONTROL, Volume：16, Number：4, First page：585, Last page：599, Apr. 2010, [Reviewed]
  A control method for achieving zero compliance to direct disturbance is proposed for a vibration isolation system. The structure of the proposed zero-compliance system is as follows. A middle mass is suspended by a spring from the base. The isolation table is suspended and moved by a linear actuator that is fixed to the middle mass. When direct disturbance acts on the isolation table, the middle mass begins to move in the same direction as the disturbance. The actuator operates to move the isolation table in the opposite direction to cancel the displacement of the middle mass to the base. To verify the effectiveness of this principle, a single-axis apparatus was fabricated. In this apparatus, the isolation table and the middle mass are guided to move horizontally to study characteristics without the influence of gravity. A voice coil motor (VCM) is installed between the isolation table and the middle mass, and integral-proportional-derivative (I-PD) control is implemented to achieve displacement cancellation control. Another VCM is installed between the middle mass and the base, and PD control is implemented for realizing the prescribed stiffness and damping. The efficacy of the designed control system is confirmed experimentally.
  SAGE PUBLICATIONS LTD, English, Scientific journal
  DOI：https://doi.org/10.1177/1077546309106151
  DOI ID：10.1177/1077546309106151, ISSN：1077-5463, Web of Science ID：WOS:000276638900009
• Proposal of damping-insensitive mass measurement with a dynamic vibration absorber　　　　　　　　　　　　　　　
  Takeshi Mizuno; Yuji Ishino; Masaya Takasaki
  17th International Congress on Sound and Vibration 2010, ICSV 2010, Volume：3, First page：2310, Last page：2316, 2010
  A new method of measuring mass is proposed which is characterized by the use of a damped dynamic vibration absorber. Various methods of measuring mass under weightless conditions have been proposed. One of them uses a dynamic vibration absorber as a measurement device. The mass measurement systems with a vibration absorber are classified into centrifugal and vibration types according to the motion of an object to be measured. In the vibration type, a measurement object is attached to the absorber mass of a dynamic vibration absorber. A vibration-type measurement system has been developed which is characterized by the use of an undamped dynamic vibration absorber. However, inevitable damping in the absorber may cause measurement error. A new method of measuring mass is proposed to overcome such a problem. A mass-spring system with a dynamic vibration absorber has a fixed point though which the frequency response curve passes independently of damping in the absorber. The proposed method utilizes this fixed point so that mass is estimated independently of damping. The principle of measurement is described based on a mathematical model. The outline of measurement and control systems are also presented. It is characterized by using the phaselocked loop (PLL) to achieve the tuning condition.
  English, International conference proceedings
  SCOPUS ID：84871451165
• G1000-3-1 Multiple Magnetic Suspension Systems : 6th report: Controllability of Gyroscopic Systems　　　　　　　　　　　　　　　
  MIZUNO Takeshi; TAKASAKI Masaya; ISHINO Yuji
  The proceedings of the JSME annual meeting, Volume：2010, First page：185, Last page：186, 2010
  The controllability of gyroscopic systems is discussed based on their basic analytical models. Two rotational motions of the rotor interacts each other due to gyroscopic effects. They are usually controlled with two control inputs in totally active magnetic bearing systems. This report treats gyrosocpic systems with a single control input. The conditions are clarified under which the systems become controllable.
  The Japan Society of Mechanical Engineers, Japanese
  DOI：https://doi.org/10.1299/jsmemecjo.2010.5.0_185
  DOI ID：10.1299/jsmemecjo.2010.5.0_185, CiNii Articles ID：110008700382, CiNii Books ID：AA11461871
• Position Estimation of Electrostatic Suspension System Using a Variable Capacitor　　　　　　　　　　　　　　　
  Kato Takaaki; Ishino Yuji; Takasaki Masaya; Mizuno Takashi
  Proceedings of JSPE Semestrial Meeting, Volume：2010, First page：981, Last page：982, 2010
  本研究では可変キャパシタを利用した静電アクチュエータ制御システムにおける，浮上体位置の推定方法について検討した．このシステムでは従来利用されていた高電圧増幅器に代わり，可変キャパシタを利用して電圧を制御できる．また，この制御システムでは可変キャパシタの静電容量とアクチュエータへの印加電圧を測定することにより，浮上体の位置が推定可能であると考えられる．今回は原理と推定値の静特性について報告する．
  The Japan Society for Precision Engineering
  DOI：https://doi.org/10.11522/pscjspe.2010S.0.981.0
  DOI ID：10.11522/pscjspe.2010S.0.981.0, CiNii Articles ID：130004660028
• Friction measurement on a glass substrate using surface acoustic wave　　　　　　　　　　　　　　　
  Hiroyuki Kotani; Masaya Takasaki; Takeshi Mizuno
  INTERNATIONAL CONGRESS ON ULTRASONICS, PROCEEDINGS, Volume：3, Number：1, First page：1067, Last page：1073, 2010, [Reviewed]
  A method to provide human tactile sensation using surface acoustic wave (SAW) was proposed. A stator transducer material (piezoelectric material) of a SAW tactile display, however, had constraint of size and shape. Previously, to solve this problem, a new method was proposed to excite and propagate SAW on a non-piezoelectric material surface. Excitation and propagation of SAW on a non-piezoelectric material is realized by combination of a LiNbO(3) plate and a glass substrate. Using the method, the glass substrate SAW tactile display could realize tactile sensation in the same manner as the conventional SAW tactile display. However, a relationship between the friction coefficient and vibration amplitude is unclear in the glass substrate SAW tactile display. To decide and optimize the control parameters of the glass substrate SAW tactile display, the relation is needed.
  In this research, the friction shifts was experimentally confirmed in the glass substrate SAW tactile display. Additionally, the relation was investigated.
  ELSEVIER SCIENCE BV, English, International conference proceedings
  DOI：https://doi.org/10.1016/j.phpro.2010.01.138
  DOI ID：10.1016/j.phpro.2010.01.138, ISSN：1875-3892, Web of Science ID：WOS:000275913100023
• A MODULAR-TYPE THREE-AXIS VIBRATION ISOLATION SYSTEM USING NEGATIVE STIFFNESS　　　　　　　　　　　　　　　
  Md. Emdadul Hogue; Takeshi Mizuno; Yuji Ishino; Masaya Takasaki
  PROCEEDINGS OF THE ASME DYNAMIC SYSTEMS AND CONTROL CONFERENCE 2010, VOL 2, First page：577, Last page：582, 2010, [Reviewed]
  A vibration isolation system is presented in this paper which is developed by the combination of multiple vibration isolation modules. Each module is fabricated by connecting a positive stiffness suspension in series with a negative stiffness suspension. Each vibration isolation module can be considered as a self-sufficient single-degree-of-freedom vibration isolation system. 3-DOF vibration isolation system can be developed by combining three modules. As the number of motions to be controlled and the number of actuators are equal, there is no redundancy in actuators in such vibration isolation systems. Experimental results are presented to verify the proposed concept of the development of MDOF vibration isolation system using vibration isolation modules.
  AMER SOC MECHANICAL ENGINEERS, English, International conference proceedings
  Web of Science ID：WOS:000319788500076
• Realization of Self-Sensing Electrostatic Suspension Using a Variable Capacitor　　　　　　　　　　　　　　　
  Takaaki Kato; Yuji Ishino; Masaya Takasaki; Takeshi Mizuno
  IECON 2010 - 36TH ANNUAL CONFERENCE ON IEEE INDUSTRIAL ELECTRONICS SOCIETY, 2010, [Reviewed]
  In order to achieve electrostatic suspension, it is necessary to control the voltage. The authors have proposed a control system using a variable capacitor. This paper describes a self-sensing control method for this system. In the previous control system, the variable capacitor was connected with an electrostatic actuator and a constant power supply. The voltage applied to the actuator can be adjusted by varying the capacitance of the variable capacitor. To this the authors now add a self-sensing control method as follows. The position can be estimated by measuring the capacitance of the variable capacitor and voltage applied to the electrostatic actuator or the variable capacitor. Based on an analysis of the static and dynamic characteristics of the estimated signal, the feasibility of self-sensing control was shown. The estimated signal was used for suspension as the feedback signal and self-sensing electrostatic suspension was achieved.
  IEEE, English, International conference proceedings
  ISSN：1553-572X, Web of Science ID：WOS:000300146000152
• Non-contact Ultrasonic Support of Minute Objects　　　　　　　　　　　　　　　
  Masaya Takasaki; Daisuke Terada; Yasuhiro Kato; Yuji Ishino; Takeshi Mizuno
  INTERNATIONAL CONGRESS ON ULTRASONICS, PROCEEDINGS, Volume：3, Number：1, First page：1059, Last page：1065, 2010, [Reviewed]
  In near-field acoustic levitation, an object is levitated vertically upward above the vibrating surface of an ultrasonic transducer. On the other hand, it is known that an object can be suspended vertically downward under the vibrating surface in the water. In this phenomenon, it seems that the pressure acting on the object is negative at the certain gap. This paper describes application of the pressure for handling of minute planar objects in the air. Fabrication of an experimental setup according to the proposal and experimental results of the ultrasonic suspension in the air are reported.
  ELSEVIER SCIENCE BV, English, International conference proceedings
  DOI：https://doi.org/10.1016/j.phpro.2010.01.137
  DOI ID：10.1016/j.phpro.2010.01.137, ISSN：1875-3892, Web of Science ID：WOS:000275913100022
• Tactile Display Using Surface Acoustic Wave　　　　　　　　　　　　　　　
  Masaya Takasaki; Ryo Tamon; Hiroyuki Kotani; Takeshi Mizuno
  ACTUATOR 10, CONFERENCE PROCEEDINGS, First page：528, Last page：532, 2010, [Reviewed]
  This paper deals with tactile display using surface acoustic wave. Basic principle to indicate human tactile sensation, especially for roughness sensation, is described. The first prototype of the display and a controller are reported. A large transducer to expand the display area size is introduced. SAW indirect excitation method to solve size problem of the piezoelectric material substrate was proposed. Trial according to the proposal and fabrication of a large glass substrate transducer are also reported.
  MESSE BREMEN-HVG HANSEATISCHE VERANSTALTUNGS-GMBH, English, International conference proceedings
  Web of Science ID：WOS:000279861200111
• DEVELOPMENT OF A MULTI-DEGREE-OF-FREEDOM VIBRATION ISOLATION SYSTEM USING PARALLEL MECHANISM　　　　　　　　　　　　　　　
  Md. Emdadul Hoque; Takeshi Mizuno; Yuji Ishino; Masaya Takasaki
  PROCEEDINGS OF THE 17TH INTERNATIONAL CONGRESS ON SOUND AND VIBRATION, 2010, [Reviewed]
  A multi-degree-of-freedom modular vibration isolation system is presented in this paper using parallel mechanism technique. To develop such vibration isolator, multiple modules are used. Each module itself can be considered as a single-degree-of-freedom vibration isolation system and can be controlled separately. Each module is capable to isolate ground vibration as well as to suppress direct disturbance on the table. As all the modules are connected by parallel mechanism between the base and the isolation table, the isolation system can insulate both disturbances in any directions. The salient feature of the system is that it does not have any redundant actuator. The experimental results are demonstrated to verify the efficacy of the proposed system.
  INT INST ACOUSTICS & VIBRATION, English, International conference proceedings
  Web of Science ID：WOS:000392489203011
• Two-Dimensional Inverted Pendulum Using Repulsive Magnetic Levitation　　　　　　　　　　　　　　　
  Max Eirich; Yuji Ishino; Masaya Takasaki; Takeshi Mizuno
  AT-AUTOMATISIERUNGSTECHNIK, Volume：58, Number：1, First page：49, Last page：53, 2010, [Reviewed]
  The active control of two-degree-of-freedom motion of the repulsive levitated object (floator) is studied In this system of permanent magnets, the vertical motions of the rotor are passively supported by repulsive forces between the permanent magnets. The inclination angle is actively stabilized using the motion control of additional magnets.
  OLDENBOURG VERLAG, English, Scientific journal
  DOI：https://doi.org/10.1524/auto.2010.0811
  DOI ID：10.1524/auto.2010.0811, ISSN：0178-2312, DBLP ID：journals/at/EirichITM10, Web of Science ID：WOS:000274374400006
• Active Horizontal Suspension System Using Negative Stiffness Control　　　　　　　　　　　　　　　
  Mhia Md Zaglul Shahadat; Takeshi Mizuno; Yuji Ishino; Masaya Takasaki
  INTERNATIONAL CONFERENCE ON CONTROL, AUTOMATION AND SYSTEMS (ICCAS 2010), First page：1946, Last page：1951, 2010, [Reviewed]
  Realizing an active horizontal suspension system using negative stiffness for attenuating the effect of direct disturbance to the isolation table is presented in this paper. The inclination of the suspension system causes dislocation of the suspended table. The vibration isolation characteristics of the proposed active system controlled by negative stiffness controller are investigated on horizontal and inclined surface in this study. Negative stiffness is accomplished between the isolation table and the middle mass and positive stiffness is accomplished between the middle mass and the base. The transfer function approach is used to design the controllers. The infinite stiffness and the corresponding zero compliance to the isolation table against direct static disturbance is achieved by series combination of the negative stiffness and positive stiffness of equal magnitude. Both the isolation table and the middle mass are driven by voice coil motors (VCMs) according to the relative displacements of the table and mass which are measured with eddy current gap sensors. The control method for realizing negative stiffness as well as infinite stiffness to the isolation table with VCM is presented analytically. The validity of this technique is confirmed experimentally and theoretically. The results show that the active system with proposed control method can suppress direct static and dynamics disturbances associated with horizontal translation.
  IEEE, English, International conference proceedings
  Web of Science ID：WOS:000294964400415
• A 3-DOF modular vibration isolation system using zero-power magnetic suspension with adjustable negative stiffness.　　　　　　　　　　　　　　　
  Md. Emdadul Hoque; Takeshi Mizuno; Yuji Ishino; Masaya Takasaki
  11th IEEE International Workshop on Advanced Motion Control, AMC 2010, Nagaoka University of Technology, Nagaoka, Niigata, Japan, March 21st - 24th, 2010, First page：661, Last page：666, 2010, [Reviewed]
  IEEE
  DOI：https://doi.org/10.1109/AMC.2010.5464051
  DOI ID：10.1109/AMC.2010.5464051, DBLP ID：conf/amc/HoqueMIT10
• Application of Switching Stiffness Control to Magnetic Suspension System for Increasing Load Capacity(Mechanical Systems)　　　　　　　　　　　　　　　
  ISHINO Yuji; MIZUNO Takeshi; TAKASAKI Masaya
  TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series C, Volume：76, Number：762, First page：415, Last page：421, 2010, [Reviewed]
  This paper presents a method of increasing the load capacity of magnetic suspension systems. The limits of coil current and suspension gap determine the load capacity. In the PID-controlled system, the displacement is kept zero and the coil current increases when load is added to the floator. In contrast the current is kept zero and the gap decreases in the zero-power controlled system. As a result the load capacity is determined by the current limit in the former and the gap limit in the latter. It can be increased by switching them each other. The switching stiffness control is applied for this purpose in this paper. Experimental results demonstrate the operating range is extended almost twice.
  一般社団法人 日本機械学会, Japanese
  ISSN：0387-5024, CiNii Articles ID：110007574846
• Multiple Magnetic Suspension Systems : 1st Report, Basic Concepts and Theorems(Mechanical Systems)　　　　　　　　　　　　　　　
  MIZUNO Takeshi; TAKASAKI Masaya; ISHINO Yuji
  TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series C, Volume：76, Number：761, First page：76, Last page：83, 2010, [Reviewed]
  The paper proposes multiple magnetic suspension systems. The concepts are presented by using their basic models. They are classified according to multiple structure, power amplifier and coil connection. According to the first item, they can be divided into series and parallel. This paper mainly treats the latter. The controllability and the observability of each parallel suspension system are discussed based on its mathematical model. The concept of sensorless magnetic suspension is stretched to the multiple systems. The feasibility of parallel magnetic suspension is demonstrated by simulation.
  一般社団法人 日本機械学会, Japanese
  ISSN：0387-5024, CiNii Articles ID：110007521085
• Micro-Assembly Using Liquid Surface Tension : 2nd Report, Study on Working Fluids(Mechanical Systems)　　　　　　　　　　　　　　　
  HAGA Tetsuya; MIZUNO Takeshi; TAKASAKI Masaya; ISHINO Yuji; KATO Yasuhiro
  TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series C, Volume：76, Number：761, First page：69, Last page：75, 2010, [Reviewed]
  The effects of surface tension on picking up a minute object by a water drop were studied experimentally. The self-centering effects of the proposed method of picking up a microchip was demonstrated in the 1st report. In this method, the stability of forming a drop and sufficient capillary force for lifting up the chip are important. This paper investigated the effect of liquid surface tension on them by using isopropanol (IPA) and its water mixture. The surface tension of water is about three times that of IPA. It was found that the maximum wetting angle on the top of nozzle increased as the ratio of IPA to water decreased. As a result, larger drops were enable to be formed as the ratio of IPA decreased. The adsorption force of a drop was measured for IPA-water mixtures. It was found that the adsorption force of a drop was sufficient to lift up a microchip.
  一般社団法人 日本機械学会, Japanese
  ISSN：0387-5024, CiNii Articles ID：110007521084
• Extension of measurement bandwidth in an AMB-based gyroscopic sensor　　　　　　　　　　　　　　　
  Yutaka Maruyama; Takeshi Mizuno; Masaya Takasaki; Yuji Ishino; Hironori Kameno
  MECHATRONICS, Volume：19, Number：8, First page：1261, Last page：1268, Dec. 2009, [Reviewed]
  A gyroscopic sensor using active magnetic bearing (AMB) is studied both theoretically and experimentally. The sensor has been proposed to realize high accuracy, compact and low-cost sensors, and it utilizes the control function of the AMB. The sensor works as a two-axis gyroscopic sensor and also as a three-axis servo-type accelerometer. Angular velocities and accelerations are measured based on the control signals for cancelling the inertial effects that act on the AMB rotor. The methods to detect the accelerations and angular velocities have been validated from several experimental results. In addition, it has been indicated that there is an upper limit in the measurement bandwidth of the sensor when the two-axis angular velocity is measured simultaneously. However, factors determining the limit have not been presented in a concrete manner. This paper discusses these factors and presents a methodology that can extend the measurement bandwidth of the sensor. The limiting factors are investigated extensively by analysis, numerical simulations and experiments with the AMB. The relationship between the measurement bandwidth and the control system is also investigated. In addition, the measurement range of the gyro is discussed. (C) 2009 Elsevier Ltd. All rights reserved.
  PERGAMON-ELSEVIER SCIENCE LTD, English, Scientific journal
  DOI：https://doi.org/10.1016/j.mechatronics.2009.08.002
  DOI ID：10.1016/j.mechatronics.2009.08.002, ISSN：0957-4158, Web of Science ID：WOS:000273183700006
• Stiffness Control by a Local Current Feedback in Magnetic Suspension Systems　　　　　　　　　　　　　　　
  石野裕二; 水野毅; 高崎正也
  日本機械学会論文集 C編, Volume：75, Number：754, First page：1763, Last page：1769, Jun. 2009, [Reviewed]
  Japanese
  DOI：https://doi.org/10.1299/kikaic.75.1763
  DOI ID：10.1299/kikaic.75.1763, ISSN：0387-5024, J-Global ID：200902298276654250
• Study on Control System for Active Magnetic Bearing Considering Motions of Stator　　　　　　　　　　　　　　　
  丸山裕; 水野毅; 高崎正也; 石野裕二; 亀野浩徳; 久保厚
  日本機械学会論文集 C編, Volume：75, Number：753, First page：1389, Last page：1396, May 2009, [Reviewed]
  This paper presents a control system for active magnetic bearings (AMBs) considering the motions of the stator. AMBs require active control for stable support of the rotor. Many control methods for AMBs have been proposed. Most of them are designed with no regard to the stator motions because the stator is usually fixed on the base. However, in some applications, the stator moves with the object in which the AMB is mounted. In this paper, the influences of the stator motions on the relative angle of the rotor to the stator are investigated both theoretically and experimentally. In addition, the signals estimated by a disturbance observer are used to compensate the influences. The influences become remarkable at a low frequency range. The upper side of the remarkable range extends to higher frequency range when the gyroscopic effect is large. The influences are cancelled by the compensation using the observer. The effect of the cancellation depends on the estimation speed of the observer.
  一般社団法人 日本機械学会, Japanese
  DOI：https://doi.org/10.1299/kikaic.75.1389
  DOI ID：10.1299/kikaic.75.1389, ISSN：0387-5024, J-Global ID：200902205577860729, CiNii Articles ID：130000150750
• An application of nonlinear compensation to six-axis vibration isolation system using zero-power control　　　　　　　　　　　　　　　
  Md. Emdadul Hoque; Takeshi Mizuno; Yuji Ishino; Masaya Takasaki
  16th International Congress on Sound and Vibration 2009, ICSV 2009, Volume：6, First page：3435, Last page：3442, 2009
  A nonlinear compensation for zero-power control and its application to six-axis vibration isolation system is addressed. In the previous study, the vibration isolation system is developed by connecting a positive stiffness spring in series with a negative stiffness suspension realized by an active zero-power control. However, zero-power control system itself has inherently nonlinear characteristics and thus, makes the zero-compliance system nonlinear. Therefore, a nonlinear compensator for zero-power control is designed and implemented to a six-axis vibration isolation system with weight support mechanism. This increases its stability and payload supporting capacity without degrading ground vibration isolation characteristics. Experimental results are presented to verify the efficacy of the developed system.
  English, International conference proceedings
  SCOPUS ID：84871424760
• Flux-path control module using a single actuator　　　　　　　　　　　　　　　
  Takeshi Mizuno; Yuta Nagano; Yuji Ishino; Masaya Takasaki
  ICCAS-SICE 2009 - ICROS-SICE International Joint Conference 2009, Proceedings, First page：4407, Last page：4410, 2009
  A novel flux-path control module was developed for magnetic suspension systems with multiple magnetic sources. The module has a pair of ferromagnetic plates and a single voice coil motor (VCM) for driving both the plates. The ferromagnetic plates are inserted between a permanent magnet and a suspended object (floator). The gap between the plates is controlled by using the VCM. Since the flux from the permanent magnet to the floator is a function of the gap, the attractive force acting on the floator can be controlled with the module. Basic characteristics of the module were measured. Noncontact suspension was achieved with the developed module. © 2009 SICE.
  English, International conference proceedings
  SCOPUS ID：77951116790
• Study on Control System for Active Magnetic Bearing Considering Motions of Stator　　　　　　　　　　　　　　　
  MARUYAMA Yutaka; MIZUNO Takeshi; TAKASAKI Masaya; ISHINO Yuji; KAMENO Hironori; KUBO Atsushi
  JSDD, Volume：3, Number：6, First page：954, Last page：965, 2009
  This paper presents a control system for active magnetic bearings (AMBs) considering the motions of the stator. AMBs require active control for stable support of the rotor. Many control methods for AMBs have been proposed. Most of them are designed with no regard to the stator motions because the stator is usually fixed on the base. However, in some applications, the stator moves with the object in which the AMB is mounted. In this paper, the influences of the stator motions on the relative angle of the rotor to the stator are investigated both theoretically and experimentally. In addition, the signals estimated by a disturbance observer are used to compensate the influences. The influences become remarkable at a low frequency range. The upper side of the remarkable range extends to higher frequency range when the gyroscopic effect is large. The influences are cancelled by the compensation using the observer. The effect of the cancellation depends on the estimation speed of the observer.
  The Japan Society of Mechanical Engineers, English
  DOI：https://doi.org/10.1299/jsdd.3.954
  DOI ID：10.1299/jsdd.3.954, ISSN：1881-3046, CiNii Articles ID：130000150750
• Proposal of a new configuration for magnetically suspended gyro　　　　　　　　　　　　　　　
  Yutaka Maruyama; Takeshi Mizuno; Masaya Takasaki; Yuji Ishino; Hironori Kameno; Atsushi Kubo
  IECON Proceedings (Industrial Electronics Conference), First page：1911, Last page：1916, 2009, [Reviewed]
  This paper proposes a new configuration for rotating gyros using magnetic suspension. A rotating gyro based on an active magnetic bearing (AMB-based gyro) has been proposed. However, the miniaturization of the AMB-based gyro is technically difficult because of the limitations on its design and structures. In contrast, the new configuration suits miniaturization because of the simplicity of rotor design. Based on the new concept, a prototype of a new rotating gyro was fabricated. The structure and the principle of angular velocity measurement are presented, as well as the control system of the new gyro. The performance of the closed-loop system is evaluated from a viewpoint of frequency response. In addition, angular velocity measurements are reported. ©2009 IEEE.
  English, International conference proceedings
  DOI：https://doi.org/10.1109/IECON.2009.5414849
  DOI ID：10.1109/IECON.2009.5414849, SCOPUS ID：77951585995
• Pen Tablet Type Surface Acoustic Wave Tactile Display Combined with Phantom　　　　　　　　　　　　　　　
  Masaya Takasaki; Ryo Tamon; Hiroyuki Kotani; Takeshi Mizuno
  2008 IEEE INTERNATIONAL CONFERENCE ON ROBOTICS AND BIOMIMETICS, VOLS 1-4, First page：671, Last page：675, 2009, [Reviewed]
  This paper describes development of a pen tablet type surface acoustic wave (SAW) tactile display. Combination of the device with a Phantom is proposed to control the display. The role of the Phantom is to detect pen position and to guide the pen inside the indication area of the display. This paper presents principle of the SA W tactile display and its application to pen tablet interface. The combination to realize our proposal is also indicated. Demonstration is reported to show effectiveness of the developed device.
  IEEE, English, International conference proceedings
  Web of Science ID：WOS:000271966900112
• Dummy Finger for Surface Acoustic Wave Tactile Display-Vibration Characteristics　　　　　　　　　　　　　　　
  Masaya Takasaki; Soju Nakajima; Takeshi Mizuno
  2009 IEEE INTERNATIONAL CONFERENCE ON ROBOTICS AND BIOMIMETICS (ROBIO 2009), VOLS 1-4, First page：1669, Last page：+, 2009, [Reviewed]
  We have already proposed a novel method to provide human tactile sensation using surface acoustic wave (SAW). A pulse modulated driving voltage excites temporal distribution of standing SAW. The distribution generates friction shift on the surface of a SAW substrate. When the surface with burst SAW is explored, the friction shift can be perceived as tactile sensation at mechanoreceptors in the finger skin. For real reproduction of tactile sensation, the burst frequency was controlled according to measured rubbing motion. To enhance the reality, we should discuss the control parameters and their arrangement. For the arrangement, vibration characteristics of fingers on the display are required. To observe the characteristics, a dummy finger is proposed. In this paper, fabrication of the dummy finger and its characteristics are reported. The discussion according to the result is also described.
  IEEE, English, International conference proceedings
  Web of Science ID：WOS:000285530501074
• Pen Type Surface Acoustic Wave Tactile Display with Movable Tablet　　　　　　　　　　　　　　　
  Masaya Takasaki; Ryo Tamon; Hiroyuki Kotani; Takeshi Mizuno
  RO-MAN 2009: THE 18TH IEEE INTERNATIONAL SYMPOSIUM ON ROBOT AND HUMAN INTERACTIVE COMMUNICATION, VOLS 1 AND 2, First page：1115, Last page：1120, 2009, [Reviewed]
  Recently, pen-tablet interface for PC has been commercialized. Using the device, its user can draw a line on it as well as point icons like a mouse. During such operation, users can feel only smoothness on the top of the pen. They cannot recognize the completion of the operation, because of no tactile sensation feedback. In this research, tactile feedback through the pen is proposed. The operators can feel drawing sensation similar to the feeling when they draw a line with a charcoal on a drawing paper. To realize the feedback, principle of surface acoustic wave (SAW) tactile display was applied. A movable tablet with a SAW transducer was designed and fabricated. With the transducer, tactile feedback can be enjoyed on whole PC screen.
  IEEE, English, International conference proceedings
  Web of Science ID：WOS:000279893100190
• ANALYSIS ON THE EFFECTS OF STIFFNESS IN MASS MEASUREMENT USING RELAY FEEDBACK OF DISPLACEMENT　　　　　　　　　　　　　　　
  Takeshi Mizuno; Yuji Ishino; Masaya Takasaki
  XIX IMEKO WORLD CONGRESS: FUNDAMENTAL AND APPLIED METROLOGY, PROCEEDINGS, First page：171, Last page：174, 2009, [Reviewed]
  This paper treats a relay-feedback mass measurement system that uses a relay with dead zone and feeds back the displacement of the object. The efficacy of the proposed method has been already confirmed experimentally. In actual measurement, however, the object to be measured was guided by a spring for avoiding rotation. The effect of stiffness produced by this spring on mass estimation has not been investigated analytically. In this paper, an estimating equation including this effect is derived. The derived equation indicates that the estimated mass is smaller than the actual one when the conventional estimating equation is used. The experiments carried out in the fabricated apparatus support well the validity of the derived estimating equation.
  IMEKO, English, International conference proceedings
  Web of Science ID：WOS:000275561600031
• Development of a Repulsive Magnetic Bearing Device with an Adjustability Function of Radial Stiffness　　　　　　　　　　　　　　　
  Max Eirich; Yuji Ishino; Masaya Takasaki; Takeshi Mizuno
  MOTION AND VIBRATION CONTROL, First page：63, Last page：70, 2009, [Reviewed]
  This paper studies the ability to adjust the stiffness in the radial direction on a non-contact levitated rotor by using an independent motion control of permanent magnets. The method of stabilization in the axial direction, by moving a magnet for support like an inverted pendulum, is applied. The repulsive forces in the radial direction depend not only on the size and physical characteristics of magnets but also on the relative positioning of magnets to each other in the axial direction. This work shows the principles and the one of necessary methods of motion control for successful adjustability of the radial stiffness.
  SPRINGER, English, International conference proceedings
  DOI：https://doi.org/10.1007/978-1-4020-9438-5_7
  DOI ID：10.1007/978-1-4020-9438-5_7, Web of Science ID：WOS:000264057300007
• Application of Rotor Unbalance Compensation to an AMB-Based Gyroscopic Sensor　　　　　　　　　　　　　　　
  MARUYAMA Yutaka; MIZUNO Takeshi; TAKASAKI Masaya; ISHINO Yuji; KAMENO Hironori; KUBO Atsushi
  Journal of System Design and Dynamics, Volume：3, Number：4, First page：572, Last page：583, 2009, [Reviewed]
  Rotor unbalance in an AMB-based gyroscopic sensor is studied in this paper. An AMB-based gyroscopic sensor has been proposed to realize a high-accuracy, low-cost and compact gyroscopic sensor. In this sensor, an active magnetic bearing (AMB) is applied as a rotating gyro, which is an instrument for measuring angular velocity. The relative position and attitude of the AMB rotor to the AMB stator are maintained using magnetic forces. Two-axis angular velocities of a measurement object are estimated from the control currents required to cancel the gyroscopic torque acting on the AMB rotor. However, the estimated signals of angular velocities include several undesirable frequency components. These components are caused by rotor unbalance and the induction motor used to spin the AMB rotor. A beat appears due to composition of these components. The beat component cannot be eliminated by filtering because it is in the measurement bandwidth of the AMB-based gyroscopic sensor. In this study, two unbalance compensation methods are applied to the AMB-based gyroscopic sensor to eliminate the beat component from the estimated measurements of angular velocities. The efficacy of each compensation method is examined experimentally.
  一般社団法人 日本機械学会, English
  CiNii Articles ID：130000132909
• Electrostatic Suspension Using Variable Capacitors　　　　　　　　　　　　　　　
  KATO Takaaki; TSUKADA Shinya; ISHINO Yuji; TAKASAKI Masaya; MIZUNO Takeshi
  Journal of System Design and Dynamics, Volume：3, Number：4, First page：617, Last page：626, 2009, [Reviewed]
  A new control system for electrostatic actuators was applied to electrostatic suspension. This control system was designed to use a variable capacitor connected with an electrostatic actuator in series. A high voltage was applied to this connection. The voltage applied to the actuator was controlled by varying the capacitance of the variable capacitor. An experimental apparatus was fabricated in order to study the controllability of electrostatic force using this control system. The experimental results show that electrostatic force can be controlled both statically and dynamically. Another experimental apparatus was fabricated for demonstrating the feasibility of electrostatic suspension. This apparatus was able to control the 3-DOF vertical motions of the suspended object. Non-contact suspension was achieved with the developed control system using variable capacitors.
  一般社団法人 日本機械学会, English
  CiNii Articles ID：130000132913
• Basic Study on Microassembly Using Surface Tension (1st Report, Principle and Basic Experiments)　　　　　　　　　　　　　　　
  高木浩; 水野毅; 高崎正也; 石野裕二
  日本機械学会論文集 C編, Volume：74, Number：741, First page：1317, Last page：1321, May 2008, [Reviewed]
  This paper proposes a new method of handling microchips. The process of handling is as follow. First, a water drop is made at the head of the nozzle. Second, the nozzle downs so that the water drop touches the chip. Third, the nozzle is lifted up. Then the chip comes to the bottom of the water drop automatically due to the gravitational force, which is called self-centering effect. Then the water drop is suctioned for the chip to be held at the head of the nozzle. This method has an advantage of catching up and positioning a chip displaced from the center of the nozzle due to the self-centering effect. Fundamental performances of this method are studied experimentally.
  一般社団法人日本機械学会, Japanese
  DOI：https://doi.org/10.1299/kikaic.74.1317
  DOI ID：10.1299/kikaic.74.1317, ISSN：0387-5024, J-Global ID：200902243809982949, CiNii Articles ID：110006685275
• Study on the Basic Characteristics of Flux‐Path Control Magnetic Suspension and Realization of Levitation　　　　　　　　　　　　　　　
  古舘宗大; 稲葉俊介; 石野裕二; 高崎正也; 水野毅
  日本機械学会論文集 C編, Volume：74, Number：741, First page：1185, Last page：1191, May 2008, [Reviewed]
  In the flux-path control magnetic suspension system, the force acting on the floater is controlled by moving a control plate made of ferromagnetic material, which is located between the permanent magnet and the floater. In this paper, the three-dimensional attractive forces acting on the floator were measured with a manufactured load cell and two sets of plate springs with strain gauges. The force actuating in the vertical direction is measured with the load cell. The force actuating in the horizontal direction is measured with the plate springs with strain gauges. These measurements clarify the relations between the positions of the control plates and the three-dimensional attractive forces. In addition, stable three-dimensional positioning was achieved by applying PD control. PD control is also applied to the flux path control modules to provide them sufficient stiffness and damping property to suspend the floator. In addition, several dynamic characteristics were measured in each direction.
  一般社団法人日本機械学会, Japanese
  DOI：https://doi.org/10.1299/kikaic.74.1185
  DOI ID：10.1299/kikaic.74.1185, ISSN：0387-5024, J-Global ID：200902211061380437, CiNii Articles ID：110006685257
• Surface Acoustic Wave Linear Motor Using Segment-Structured Diamond-Like Carbon Films on Contact Surface (1st Report) : Deposition on Driving Surface and Driving Experiment　　　　　　　　　　　　　　　
  KOTANI Hiroyuki; FUJII Yousuke; TAKASAKI Masaya; ADACHI Yusuke; AOKI Yuichi; OTAKE Naoto; MIZUNO Takeshi
  Journal of the Japan Society of Precision Engineering, Volume：74, Number：7, First page：724, Last page：729, 2008
  Surface acoustic wave (SAW) linear motor is a kind of ultrasonic motors. The advantages of the SAW linear motor is thin structure, high force, high speed and precise positioning. On the other hand, the motor has a problem with wear of contact surface. The SAW linear motor consist of a LiNbO_3 as a stator transducer and a silicon substrate with distributed projections as a slider. However, the stator transducer material is easy to wear out due to friction drive. Moreover the silicon projections enhanced wearing. Lifetime of the motor is reduced by the wear of the stator. To solve this problem, the silicon substrate with segment structured diamond-like carbon (S-DLC) films is applied as the slider instead of the silicon slider with projections. The films are expected to increase abrasion-resistant performance of contact surface and acquire the same driving characteristics as the conventional silicon slider. This report presents installation of the films on the slider surface and successful work of the motor. Observation of its performance is also indicated to be compared with the conventional one. The films deposition on a stator transducer is introduced. Successful driving of the motor with the stator transducer is also described.
  The Japan Society for Precision Engineering, Japanese
  DOI：https://doi.org/10.2493/jjspe.74.724
  DOI ID：10.2493/jjspe.74.724, ISSN：0912-0289, CiNii Articles ID：110006827293, CiNii Books ID：AN1003250X
• An application of relay feedback to mass measurement under weightless conditions　　　　　　　　　　　　　　　
  Takeshi Mizuno; Yuji Ishino; Minoru Takeuchi; Masaya Takasaki
  2007 Proceedings of the ASME International Design Engineering Technical Conferences and Computers and Information in Engineering Conference, DETC2007, Volume：4, First page：285, Last page：290, 2008, [Reviewed]
  Relay feedback was applied to measuring mass even under weightless conditions. A measurement object is driven by a force-output actuator. The motion of the object is controlled by a relay feedback system. The used relay element has dead zone and switches force acting on the object in relation to the position of the measurement object. The mass of the object is determined from the time interval measurement of the on-state and off-state periods. An apparatus was developed for experimental study. It uses a voice coil motor as an actuator, and a pair of photo interrupters for detecting the switching positions. The effects of system parameters on measurement accuracy were studied experimentally. Under the tuned conditions, the measurement errors were within 0.2[%]. Measurement on a base moving freely was also carried out. Copyright © 2007 by ASME.
  English, International conference proceedings
  DOI：https://doi.org/10.1115/DETC2007-34709
  DOI ID：10.1115/DETC2007-34709, SCOPUS ID：44849121559
• Active stabilization of repulsive magnetic bearing by using independent motion control of permanent magnets　　　　　　　　　　　　　　　
  Max Eirich; Yuji Ishino; Masaya Takasaki; Takeshi Mizuno
  DETC2007: PROCEEDINGS OF THE ASME INTERNATIONAL DESIGN ENGINEERING TECHNOLOGY CONFERENCE AND COMPUTERS AND INFORMATION IN ENGINEERING CONFERENCE, VOL 4, First page：291, Last page：296, 2008, [Reviewed]
  This paper investigates the control system design of magnetic forces using independent motion control of permanent magnets. In the permanent magnet bearing system, the radial motions of the rotor are passively supported by repulsive forces between ring-shape permanent magnets. The experimental results demonstrate that non contact levitation is achieved by independently PD controlled axial motion of permanent magnets driven by voice coil motors (VCM).
  AMER SOC MECHANICAL ENGINEERS, English, International conference proceedings
  Web of Science ID：WOS:000254341600033
• Pen Tablet Type Surface Acoustic Wave Tactile Display Integrated with Visual Information　　　　　　　　　　　　　　　
  Masaya Takasaki; Ryo Tamon; Hiroyuki Kotani; Takeshi Mizuno
  2008 INTERNATIONAL CONFERENCE ON MECHATRONICS AND AUTOMATION: (ICMA), VOLS 1 AND 2, First page：356, Last page：+, 2008, [Reviewed]
  This paper describes development of a pen tablet type surface acoustic wave (SAW) tactile display. Combination of the device with a pen tablet LCD device is proposed. The role of the device is to detect pen position and to provide visual information. This paper presents principle of the SAW tactile display and its application to pen tablet interface integrated with visual information. The combination to realize our proposal is also indicated. Demonstration method and measurement result of mechanical vibration of the pen are also reported.
  IEEE, English, International conference proceedings
  Web of Science ID：WOS:000267671500065
• Analysis on the Effect of Stiffness on Mass Measurement Using a Relay Feedback of Velocity　　　　　　　　　　　　　　　
  Takeshi Mizuno; Yuji Ishino; Masaya Takasaki
  2008 PROCEEDINGS OF SICE ANNUAL CONFERENCE, VOLS 1-7, First page：2549, Last page：2552, 2008, [Reviewed]
  This paper treats a relay-feedback mass measurement system that uses a relay with hysteresis and feeds back the velocity of the object. The efficacy of the proposed method has been already confirmed experimentally. In actual measurement, however, a spring-like element must be added for avoiding the drift of the object. The effect of this spring on mass estimation has not been investigated analytically. In this paper, an estimating equation including this effect is derived. The derived equation indicates that the estimated mass is smaller than the actual value when the conventional estimating equation is used. The experiments carried out in the fabricated apparatus support well the validity of the derived estimating equation.
  IEEE, English, International conference proceedings
  Web of Science ID：WOS:000263966702028
• An Application of Active Magnetic Bearing to Gyroscopic and Inertial Sensors　　　　　　　　　　　　　　　
  MARUYAMA Yutaka; MIZUNO Takeshi; TAKASAKI Masaya; ISHINO Yuji; ISHIGAMI Takayuki; KAMENO Hironori
  Journal of System Design and Dynamics, Volume：2, Number：1, First page：155, Last page：164, 2008, [Reviewed]
  A new gyroscopic sensor using active magnetic bearing (AMB) is studied both theoretically and experimentally. The proposed sensor works as a two-axis gyroscopic sensor and also as a three-axis servo-type accelerometer, which utilizes the control function of AMB. Angular velocities and accelerations are estimated from the control signals for canceling gyroscopic torque and inertial forces acting on the shaft of the AMB. In measuring two-axis angular velocity simultaneously, the control signals canceling inertial torque must be considered in addition to the gyroscopic toque for precise measurement. This paper presents the principles of two-axis angular velocity and acceleration measurement by AMB. In order to investigate the feasibility of the proposed sensor, several basic studies are carried out with a conventional-size AMB.
  一般社団法人 日本機械学会, English
  CiNii Articles ID：130000098873
• Mass Measurement System Using Relay Feedback with Hysteresis　　　　　　　　　　　　　　　
  MIZUNO Takeshi; ADACHI Takahiro; TAKASAKI Masaya; ISHINO Yuji
  Journal of System Design and Dynamics, Volume：2, Number：1, First page：188, Last page：196, 2008, [Reviewed]
  Mass measurement using a relay feedback system was studied experimentally. The measurement system has an on-off relay with hysteresis and switches force acting on the object in relation to its velocity. Such nonlinear control induces a limit cycle in the feedback system. The mass of the object is determined from the period of this limit cycle. The apparatus manufactured for experimental study uses two voice coil motors (VCM's), one of which is for driving the object and the other is for generating prescribed disturbances. The effects of system parameters and disturbances on measurement accuracy were examined experimentally.
  一般社団法人 日本機械学会, English
  CiNii Articles ID：130000098876
• Three-Dimensional Force Measurement and Control of a Flux-Path Control Magnetic Suspension　　　　　　　　　　　　　　　
  FURUTACHI Munehiro; INABA Shunsuke; ISHINO Yuji; TAKASAKI Masaya; MIZUNO Takeshi
  Journal of System Design and Dynamics, Volume：2, Number：6, First page：1239, Last page：1249, 2008, [Reviewed]
  In the flux-path control magnetic suspension system, the force acting on a floator is controlled by moving a control plate made of ferromagnetic material, which is located between the permanent magnet and the floator. In this paper, the three-dimensional attractive forces acting on the floator were measured with a manufactured force sensor. The force actuating in the vertical direction is measured with the load cell built in the sensor. The force actuating in the horizontal direction is measured with the plate springs with strain gauges. These measurements clarify the relations between the positions of the control plates and the three-dimensional attractive forces. In addition, stable suspension and three-dimensional positioning were achieved by applying PD control. Several dynamic characteristics were measured in both the vertical and horizontal directions.
  一般社団法人 日本機械学会, English
  CiNii Articles ID：130000099033
• Ultra Low-Velocity Control of a Surface Acoustic Wave Linear Motor　　　　　　　　　　　　　　　
  KOTANI Hiroyuki; TAKASAKI Masaya; ISHINO Yuji; MIZUNO Takeshi
  Journal of System Design and Dynamics, Volume：2, Number：2, First page：497, Last page：506, 2008, [Reviewed]
  A surface acoustic wave (SAW) linear motor is a kind of ultrasonic motor. The advantages of the SAW linear motor are thin structure, high thrust force, high velocity and precise positioning. The relationship between applied current and output velocity is, however, unstable in the low velocity range due to the friction drive principle. Therefore the SAW linear motor cannot obtain stable driving without feedback control in the low-velocity region. In this research, to realize low velocity, a pulse width modulation (PWM) control and flexible slider structure are employed. Flexible structure is installed to cancel vibration due to the PWM carrier wave. A lower velocity in the unstable range is realized. Moreover we change the calculation algorithm for the slider velocity measurement. As a result, the SAW linear motor can be driven at an ultra low velocity of 30&mu;m/s. Additionally, driving characteristics are improved using a feedforward controller.
  一般社団法人 日本機械学会, English
  CiNii Articles ID：130000098847
• Vibration isolation system combining zero-power magnetic suspension with springs　　　　　　　　　　　　　　　
  Takeshi Mizuno; Masaya Takasaki; Daisuke Kishita; Keiichiro Hirakawa
  CONTROL ENGINEERING PRACTICE, Volume：15, Number：2, First page：187, Last page：196, Feb. 2007, [Reviewed]
  An active vibration isolation system using zero-power magnetic suspension was studied analytically and experimentally. Since a zeropower magnetic suspension system behaves as if it has negative stiffness, connecting it in series with a normal spring can generate infinite stiffness against disturbances acting on an isolation table. This property is maintained even when a suspension that supports the weight of the isolation table is introduced in parallel with the serial combination. Analysis of a simple model involving a single-axis apparatus clarified the fundamental characteristics of the system. The force-displacement characteristics of the zero-power magnetic suspension were measured to estimate the negative stiffness properties. It was experimentally confirmed that combining a zero-power magnetic suspension with a normal spring generates high stiffness against static direct disturbances acting on an isolation table. (c) 2006 Elsevier Ltd. All rights reserved.
  PERGAMON-ELSEVIER SCIENCE LTD, English, Scientific journal
  DOI：https://doi.org/10.1016/j.conengprac.2006.06.001
  DOI ID：10.1016/j.conengprac.2006.06.001, ISSN：0967-0661, Web of Science ID：WOS:000242760200005
• Vibration isolation unit combining a air spring with a voice coil motor for negative stiffness　　　　　　　　　　　　　　　
  Takeshi Mizuno; Yasuhiro Unno; Masaya Takasaki; Yuji Ishino
  2007 European Control Conference, ECC 2007, First page：3153, Last page：3158, 2007
  A vibration isolation unit for constructing multi-axis systems was developed. The unit consists of a base, an air spring, a middle mass, a voice coil motor (VCM) and an isolation table. The air spring suspends the middle mass on the base. The VCM is used to realize a suspension with negative stiffness (negative spring), which is connected to the air spring through the middle mass and suspends the isolation table. Such serial connection of a positive spring and a negative spring enables the isolation system to have high stiffness against direct disturbance even with soft springs. The validity of this method is confirmed experimentally with the manufactured unit. A two-axis vibration isolation system was constructed with two units. It was demonstrated that the position and attitude of the isolation table was maintained even in the presence of a moving mass on the isolation table.
  Institute of Electrical and Electronics Engineers Inc., English, International conference proceedings
  DOI：https://doi.org/10.23919/ecc.2007.7068435
  DOI ID：10.23919/ecc.2007.7068435, SCOPUS ID：84927722959
• Resonance frequency tracing system for Langevin type ultrasonic transducers　　　　　　　　　　　　　　　
  Masaya Takasaki; Yutaka Maruyama; Takeshi Mizuno
  2007 IEEE INTERNATIONAL CONFERENCE ON MECHATRONICS AND AUTOMATION, VOLS I-V, CONFERENCE PROCEEDINGS, First page：3817, Last page：3822, 2007, [Reviewed]
  This paper proposes a system to trace resonance. frequencies of Langevin type ultrasonic transducers. The system consists of a microcomputer, detecting circuits and a direct digital synthesizer. Fabrication of the system is reported. Step responses are described as tracing performance. Vibration amplitude modulation using the system is also indicated as an application for mechatronics.
  IEEE, English, International conference proceedings
  Web of Science ID：WOS:000251178104117
• Pen tablet interface using surface acoustic wave tactile display　　　　　　　　　　　　　　　
  Masaya Takasaki; Ji HongXu; Hiroyuki Kotani; Takeshi Mizuno
  PROCEEDINGS OF SICE ANNUAL CONFERENCE, VOLS 1-8, First page：620, Last page：623, 2007, [Reviewed]
  This paper deals with proposal of a pen tablet interface combined with surface acoustic wave(SAW) tactile display. Basic principle of the tactile display and its application for our proposal are described. Design and fabrication of an ultrasonic transducer are also reported Development of the proposed interface using the same controller as the conventional SAW tactile display is explained. Measurement result of vibration on the top of the pen indicates realization of the proposed interface.
  IEEE, English, International conference proceedings
  Web of Science ID：WOS:000255608500119
• Application of surface acoustic wave tactile display for pen tablet interface with visual information　　　　　　　　　　　　　　　
  Masaya Takasaki; Ji Hong Xu; Hiroyuki Kotani; Takeshi Mizuno
  2007 IEEE INTERNATIONAL CONFERENCE ON ROBOTICS AND BIOMIMETICS, VOLS 1-5, First page：1024, Last page：1028, 2007, [Reviewed]
  This paper deals with proposal of a pen tablet interface combined with visual information. The interface employs surface acoustic wave (SAW) tactile display. Basic principle of the tactile display and its application for our proposal are described. Design. and fabrication of an ultrasonic transducer are also reported. Development of the proposed interface using the same controller as the conventional SAW tactile display is explained. Measurement result of vibration on the top of the pen indicates realization of the proposed interface.
  IEEE, English, International conference proceedings
  Web of Science ID：WOS:000257065801013
• Estimation method and measurement bandwidth of gyroscopic sensor using active magnetic bearing　　　　　　　　　　　　　　　
  Yutaka Maruyama; Takeshi Nlizuno; Masaya Takasaki; Yuji Ishino; Takayuki Ishigami; Hironori Kameno
  IECON 2007: 33RD ANNUAL CONFERENCE OF THE IEEE INDUSTRIAL ELECTRONICS SOCIETY, VOLS 1-3, CONFERENCE PROCEEDINGS, First page：2230, Last page：+, 2007, [Reviewed]
  A gyroscopic sensor using active magnetic bearings (AMB) is studied in this paper. The sensor utilizes the control function of AMB and works as a two-axis gyroscopic sensor and also as a three-axis servo-type accelerometer. This paper focuses on angular velocity measurement. Angular velocities are estimated from the control signals for canceling gyroscopic and inertial toques acting on the shaft of the AMB. In measuring two-axis angular velocity simultaneously, there is a limit of the measuring range. In this paper, several numerical simulations and experiments with a conventional-size AMB are used to investigate this limit. In addition, the relationship between the measurement range and the control system is shown.
  IEEE, English, International conference proceedings
  ISSN：1553-572X, Web of Science ID：WOS:000253451402028
• Surface acoustic wave tactile display using a large size glass transducer　　　　　　　　　　　　　　　
  Hiroyuki Kotani; Masaya Takasaki; Takeshi Mizuno
  2007 IEEE INTERNATIONAL CONFERENCE ON MECHATRONICS AND AUTOMATION, VOLS I-V, CONFERENCE PROCEEDINGS, First page：198, Last page：203, 2007, [Reviewed]
  A method to provide human tactile sensation using surface acoustic wave (SAW) was proposed. A stator transducer material (piezoelectric material) of a SAW tactile display, however, had constraint of size and shape. In this research,. to solve this problem, a new method has been proposed to excite and propagate SAW on a non-piezoelectric material surface. Excitation and propagation of SAW on a non-piezoelectric material is realized by a combination of a LiNbO3 plate and a glass substrate. This paper describes design and fabrication of a large sized glass substrate transducer for the novel method to indicate tactile sensation using SAW. The design employs the novel transducer structure, which has been proposed previously. Using the transducer, two-dimensional rubbing motion is available. This paper also reports measurement result of speed of a slider under control. The result indicates successful display of roughness sensation based on the tactile display principle proposed by authors.
  IEEE, English, International conference proceedings
  Web of Science ID：WOS:000251178100034
• Application of displacement cancellation control to vibration isolation system　　　　　　　　　　　　　　　
  Takeshi Mizuno; Takehiko Furushima; Yuji Ishino; Masaya Takasaki
  2007 INTERNATIONAL CONFERENCE ON CONTROL, AUTOMATION AND SYSTEMS, VOLS 1-6, First page：2088, Last page：2091, 2007, [Reviewed]
  A control method achieving infinite stiffness to direct disturbance is applied to a vibration isolation system. The structure of the studied vibration isolation system is as follows. A middle mass is suspended by a spring from the base. The isolation table is suspended and moved by a linear actuator that is fixed to the middle mass. When direct vibration acts on the isolation table, the middle mass is displaced in the same direction of the force. The actuator operates to move the isolation table in the opposite direction to cancel the displacement of the middle mass to the base. To verify the effectiveness of this principle, a single-axis apparatus is fabricated. In this apparatus, the isolation table and the middle mass are guided to move horizontally for studying the characteristics without the influence of gravity. This apparatus uses two linear DC motors. One is installed between the isolation table and the middle mass and implemented with a PD controller for realizing a prescribed stiffness. The other is installed between the middle mass and the base, and implemented with an I-PD controller for realizing displacement cancellation. The efficacy of the control method is confirmed experimentally.
  IEEE, English, International conference proceedings
  Web of Science ID：WOS:000256464302028
• General forms of controller realizing negative stiffness　　　　　　　　　　　　　　　
  Takeshi Mizuno; Takehiko Furushima; Yuji Ishino; Masaya Takasaki
  PROCEEDINGS OF SICE ANNUAL CONFERENCE, VOLS 1-8, First page：2986, Last page：2991, 2007, [Reviewed]
  The zero-power magnetic suspension system behaves as if it has negative stiffness. Suspension with a similar characteristic can be realized by using a linear actuator such as a voice coil motor. The controllers realizing negative stiffness with a linear actuator are compared with zero-power controllers analytically. The analyses show that they have similar structures. It is pointed out that a control technique, which was effective in widening the operation range of zero-power controllers, can be applied to the controllers realizing negative stiffness.
  IEEE, English, International conference proceedings
  Web of Science ID：WOS:000255608503129
• A glass substrate transducer for surface acoustic wave tactile display　　　　　　　　　　　　　　　
  Masaya Takasaki; Hiroyuki Kotani; Takeshi Mizuno
  2007 RO-MAN: 16TH IEEE INTERNATIONAL SYMPOSIUM ON ROBOT AND HUMAN INTERACTIVE COMMUNICATION, VOLS 1-3, First page：319, Last page：324, 2007, [Reviewed]
  We had proposed a novel method to provide human tactile sensation using surface acoustic wave (SAW). A pulse modulated driving voltage is applied to reproduce human tactile sensation. To expand its application, a glass substrate SAW transducer has been proposed. The glass substrate transducer worked successfully. In the application, however, user's rubbing motion was limited to one-dimensional motion. To expand tactile display application, a wide and long transducer would be required. Such a transducer can realize two-dimensional tactile display. To improve energy efficiency, a new design of the transducer was proposed. This paper describes design of the new glass substrate transducer and its fabrication. Characteristics of the transducer are also reported.
  IEEE, English, International conference proceedings
  Web of Science ID：WOS:000255993700058
• Flux-Path Control Magnetic Suspension System Using Voice Coil Motors　　　　　　　　　　　　　　　
  MIZUNO Takeshi; HIRAI Yuzo; ISHINO Yuji; TAKASAKI Masaya
  Journal of System Design and Dynamics, Volume：1, Number：2, First page：147, Last page：158, 2007, [Reviewed]
  A novel magnetic suspension system with three flux-path control modules was developed. The module consists of a ferromagnetic plate, a voice coil motor (VCM) for driving the plate and a displacement sensor for detecting the position of the plate; the sensor is comprised of a V-shape plate spring and four strain gauges pasted on it. The ferromagnetic plate is inserted into the gap between a permanent magnet and a suspended object (floator). The lateral position of the plate is controlled by using the VCM and the sensor. Since the flux from the permanent magnet to the floator varies according to the position, the amplitude and direction of the attractive force acting on the floator can be adjusted with multiple modules. Stable suspension was achieved by applying PD control. A fluctuation was observed in the position of the floator. It was reduced by feeding back the lateral motions of the floator. The two-dimensional and three-dimensional noncontact manipulation of the floator was also achieved in the developed magnetic suspension system.
  一般社団法人 日本機械学会, English
  CiNii Articles ID：130000098953
• Development of a three-axis active vibration isolator using zero-power control　　　　　　　　　　　　　　　
  Hoque Emdadul; Takasaki Masaya; Ishino Yuji; 水野 毅
  IEEE-ASME TRANSACTIONS ON MECHATRONICS, Volume：11, Number：4, First page：462, Last page：470, 2007, [Reviewed]
  This paper presents the development of an active 3-degree-of-freedom (DoF) vibration isolation system using zero-power magnetic suspension. The developed system is capable to suppress direct disturbances and isolate ground vibrations of the 3-DoF motions, associated with vertical translational and rotational modes. Two categories of control strategy for the actuators are proposed, i.e., local control and mode control. The latter method allows to overcome limitations of the poor performances for rotational modes exhibited by the former. A mathematical model of the system is derived and each DoF motion is treated separately for the control system. It is demonstrated analytically that the infinite stiffness to static direct disturbances can be generated and the resonance peak due to floor vibration can effectively be suppressed for the system. Moreover, the experiments have been carried out to measure the static and dynamic responses of the isolation table to direct disturbances, and transmissibility characteristic of the isolator from the floor. The results indicate good vibration isolation and attenuation performances, and show the efficacy of the developed isolator for industrialization.(c)2007 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE.
  IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, English
  ISSN：1083-4435, CiNii Articles ID：120006385445
• An active micro vibration isolator with zero-power controlled magnetic suspension technology　　　　　　　　　　　　　　　
  Md. Emdadul Hoque; Masaya Takasaki; Yuji Ishino; Hiro-Hisa Suzuki; Takeshi Mizuno
  JSME INTERNATIONAL JOURNAL SERIES C-MECHANICAL SYSTEMS MACHINE ELEMENTS AND MANUFACTURING, Volume：49, Number：3, First page：719, Last page：726, Sep. 2006, [Reviewed]
  In this paper, a three-degree-of-freedom vibration isolation system using active zeropower controlled magnetic suspension is presented in order to isolate vibrations transmitted from the ground and to attenuate the effect of direct disturbances on the table. The zero-compliance of the isolator for direct disturbances was realized by connecting a conventional mechanical spring in series with a negative spring produced by an active magnetic suspension mechanism. In this work, each degree-of-freedom-of-motion of the vibration isolator is treated analytically and it is shown that the developed system is capable to generate infinite stiffness in each mode. Experimental studies have been conducted as well to measure the effectiveness of the isolator under both types of disturbances. Further improvements for the developed system as well as the control techniques are also discussed.
  JAPAN SOC MECHANICAL ENGINEERS, English, Scientific journal
  DOI：https://doi.org/10.1299/jsmec.49.719
  DOI ID：10.1299/jsmec.49.719, ISSN：1344-7653, Web of Science ID：WOS:000241538900014
• A Nonlinear Compensator of Zero-Power Magnetic Suspension for Zero-Compliance to Direct Disturbance　　　　　　　　　　　　　　　
  HOQUE Md. Emdadul; MIZUNO Takeshi; TAKASAKI Masaya; ISHINO Yuji
  Trans, the Society of Instrument and Control Engineering, Volume：42, Number：9, First page：1008, Last page：1016, Sep. 2006, [Reviewed]
  計測自動制御学会, English
  ISSN：0453-4654, CiNii Articles ID：10018250516
• Magnetic suspension system using three flux path control modules　　　　　　　　　　　　　　　
  Takeshi Mizuno; Yuzo Hirai; Yuji Ishino; Masaya Takasaki
  IFAC Proceedings Volumes (IFAC-PapersOnline), Volume：4, Number：1, First page：554, Last page：558, 2006
  A new magnetic suspension system is developed which has three modules for flux path control. The module consists of a ferromagnetic plate inserted between a permanent magnet and a suspended object, an actuator for driving the plate and a sensor for detecting the motion of the plate. Since the flux from the permanent magnet to the object varies according to the lateral position of the plate, the suspension force can be controlled with the module. The module uses a voice coil motor as the actuator. Stable suspension and a three-dimensional noncontact manipulation are achieved in the developed system. Copyright © 2006 IFAC.
  IFAC Secretariat, English, International conference proceedings
  DOI：https://doi.org/10.3182/20060912-3-de-2911.00097
  DOI ID：10.3182/20060912-3-de-2911.00097, ISSN：1474-6670, SCOPUS ID：79961164234
• A model-based controller for a vibration isolation system with weight support springs　　　　　　　　　　　　　　　
  Md. Emdadul Hoque; Takeshi Mizuno; Yuji Ishino; Masaya Takasaki
  IFAC Proceedings Volumes (IFAC-PapersOnline), Volume：4, Number：1, First page：662, Last page：667, 2006
  This paper is aimed to design a zero-power controller based on the theoretical model and to implement it into a vibration isolation system. To develop the vibration isolation system which is able to isolate ground vibrations as well as to suppress direct disturbance, a positive passive suspension is connected in series with an active negative spring at the outset. The system is further reinforced by using a weight support mechanism to enhance the performance for supporting heavy payloads and/ or developing large isolation table. The characteristic of the developed system is treated analytically and the efficacy of the controller performances is verified experimentally. Copyright © 2006 IFAC.
  IFAC Secretariat, English, International conference proceedings
  DOI：https://doi.org/10.3182/20060912-3-de-2911.00115
  DOI ID：10.3182/20060912-3-de-2911.00115, ISSN：1474-6670, SCOPUS ID：79961146095
• Vibration isolation system using zero-power magnetic suspension (2nd report, introduction of weight support mechanism)　　　　　　　　　　　　　　　
  Takeshi Mizuno; Daisuke Kishita; Masaya Takasaki; Yuji Ishino
  Nihon Kikai Gakkai Ronbunshu, C Hen/Transactions of the Japan Society of Mechanical Engineers, Part C, Volume：72, Number：3, First page：714, Last page：722, 2006
  Vibration isolation system using zero-power magnetic suspension is modified. A suspension spring is introduced in parallel with a series connection of a zero-power-controlled magnetic suspension and a normal spring that were used in the previous works. It can reduce the load force that the zero-power magnetic suspension has to bear. A basic configuration of the modified vibration isolation system is shown. It is demonstrated both analytically and experimentally that the modified system maintains infinite stiffness against static direct disturbance even if such a spring is added. The characteristics to dynamic direct disturbances are also studied experimentally.
  Japan Society of Mechanical Engineers, Japanese, Scientific journal
  DOI：https://doi.org/10.1299/kikaic.72.714
  DOI ID：10.1299/kikaic.72.714, ISSN：0387-5024, SCOPUS ID：33745030866
• Two-dimensional active type surface acoustic wave tactile display on a computer screen　　　　　　　　　　　　　　　
  Masaya Takasaki; Hiroyuki Kotani; Takeshi Mizuno; Takaaki Nara
  SYMPOSIUM ON HAPTICS INTERFACES FOR VIRTUAL ENVIRONMENT AND TELEOPERATOR SYSTEMS 2006, PROCEEDINGS, First page：49, Last page：54, 2006, [Reviewed]
  We have already proposed a novel method to provide human tactile sensation using surface acoustic wave (SAW). A pulse modulated driving voltage excites temporal distribution of standing SAW. The distribution generates friction shift on the surface of a SAW substrate. When the surface with the burst SAW is explored through a slider by a finger, the friction shift generates a mechanical vibration similar to a stick-slip vibration on the finger. The vibration can be perceived as tactile sensation at mechanoreceptors in the finger skin. Controlling the burst frequency according to measured rubbing motion, reality of the displayed sensation can be enhanced. In this research, we install the tactile display with a transparent stator transducer on a computer screen. Two-dimensional rubbing motion is available for the display. An experimental apparatus with finger motion capture system is fabricated on trial and controlled according to the captured motion. In a demonstration, operators can rub on a solid mark under the display to recognize its shape through tactile sensation.
  IEEE COMPUTER SOC, English, International conference proceedings
  DOI：https://doi.org/10.1109/VR.2006.136
  DOI ID：10.1109/VR.2006.136, Web of Science ID：WOS:000237225000007
• 3734 Mass measurement using the oscillation of a relay control system with velocity feedback　　　　　　　　　　　　　　　
  ADACHI Takahiro; ISHINO Yuji; TAKASAKI Masaya; MIZUNO Takeshi
  The proceedings of the JSME annual meeting, Volume：2006, First page：435, Last page：436, 2006
  This paper presents a method of mass measurement in weightless conditions, which uses the oscillation of a relay control system with velocity feedback. Factors for measurement errors are examined experimentally. The examined factors are the stiffness, viscous damping and delay time in the controller. The effects of each factor on measurement were clarified experimentally.
  The Japan Society of Mechanical Engineers, Japanese
  DOI：https://doi.org/10.1299/jsmemecjo.2006.5.0_435
  DOI ID：10.1299/jsmemecjo.2006.5.0_435, CiNii Articles ID：110006635617, CiNii Books ID：AA11461871
• Basic study on magnetic suspension by using the control of mutual inductance　　　　　　　　　　　　　　　
  Takeshi Mizuno; Yusuke Itani; Yuji Ishino; Masaya Takasaki
  IECON 2006 - 32ND ANNUAL CONFERENCE ON IEEE INDUSTRIAL ELECTRONICS, VOLS 1-11, First page：2565, Last page：+, 2006, [Reviewed]
  This paper studies a noble magnetic suspension whose suspension force is controlled with a variable mutual inductance mechanism. The suspension system has a transformer whose primary coil is energized by an AC power supply. The secondary coil is connected to the coil of an electromagnet for producing suspension force. The variable mutual inductance mechanism changes the coupling factor between the primary and secondary coils according to command signal. Since the voltage induced in the secondary coil is a function of the coupling factor, the suspension force can be adjusted with the mechanism. An experimental apparatus for single-axis magnetic suspension was fabricated. The controllability of suspension force was experimentally confirmed with the developed apparatus.
  IEEE, English, International conference proceedings
  ISSN：1553-572X, Web of Science ID：WOS:000245905005013
• Proposal of tele-touch using active type SAW tactile display　　　　　　　　　　　　　　　
  Masaya Takasaki; Yousuke Fujii; Hiroyuki Kotani; Takeshi Mizuno; Takaaki Nara
  2006 IEEE/RSJ INTERNATIONAL CONFERENCE ON INTELLIGENT ROBOTS AND SYSTEMS, VOLS 1-12, First page：1032, Last page：1037, 2006, [Reviewed]
  We have already proposed a novel method to provide human tactile sensation using surface acoustic wave (SAW). In this paper, we propose "tele-touch", which realize reproduction of tactile sensation as if to rub remote solid surface. To generate tactile display control parameters, object surface is measured by a fabricated profile scanner. Control parameters are generated from the result. To indicate various texture, we install amplitude modulation for SAW excitation. Demonstration to reproduce the tactile feeling of sample surface with the control parameters and the modulation drive is carried out.
  IEEE, English, International conference proceedings
  Web of Science ID：WOS:000245452401008
• Glass substrate surface acoustic wave tactile display with visual information　　　　　　　　　　　　　　　
  Hiroyuki Kotani; Masaya Takasaki; Takeshi Mizuno; Takaaki Nara
  IEEE ICMA 2006: PROCEEDING OF THE 2006 IEEE INTERNATIONAL CONFERENCE ON MECHATRONICS AND AUTOMATION, VOLS 1-3, PROCEEDINGS, First page：1, Last page：+, 2006, [Reviewed]
  Previously, a novel method to provide human tactile sensation using surface acoustic wave (SAW) was proposed. A stator transducer material (piezoelectric material) of a SAW tactile display, however, had constraint of size and shape. In this research, to solve this problem, a new method is proposed to excite and propagate SAW on a non-piezoelectric material surface. Excitation and propagation of SAW on a non-piezoelectric material is realized by a combination of a LiNbO3 plate and a glass substrate. Successful work of an active type SAW tactile display using the glass transducer is reported. Additionally, installation of the glass transducer on an LCD to indicate tactile sensation with visual information and its demonstration are described.
  IEEE, English, International conference proceedings
  Web of Science ID：WOS:000241434600001
• An active zero-power control with a passive technique for vibration isolation system　　　　　　　　　　　　　　　
  Md Emdadul Hoque; Takeshi Mizuno; Masaya Takasaki; Yuji Ishino
  2006 IEEE INTERNATIONAL CONFERENCE ON INDUSTRIAL TECHNOLOGY, VOLS 1-6, First page：1473, Last page：+, 2006, [Reviewed]
  This paper presents a vibration isolation system by using an active zero-power control incorporated with a passive technique. A positive stiffness spring is connected to a negative spring of equal magnitude in series to generate a high stiffness for on-board generated direct disturbances. The system is capable of isolating floor vibration as well due to the use of lower positive spring in the lower suspension. To reduce the load that the zero-power control system supports, a weight support mechanism is introduced. The proposed system paves the way for developing low cost vibration isolator with no power consumption in the steady-state. The mathematical model is analyzed such that it can generate infinite (high) stiffness for direct disturbance which is verified by experimental demonstrations.
  IEEE, English, International conference proceedings
  Web of Science ID：WOS:000248430902079
• ゼロパワー磁気浮上を利用した除振装置の開発 : 第2報,荷重支持機構の導入(機械力学,計測,自動制御)　　　　　　　　　　　　　　　
  水野 毅; 木下 大輔; 高崎 正也; 石野 裕二
  Volume：72, Number：715, First page：714, Last page：722, 2006, [Reviewed]
  Vibration isolation system using zero-power magnetic suspension is modified. A suspension spring is introduced in parallel with a series connection of a zero-power-controlled magnetic suspension and a normal spring that were used in the previous works. It can reduce the load force that the zero-power magnetic suspension has to bear. A basic configuration of the modified vibration isolation system is shown. It is demonstrated both analytically and experimentally that the modified system maintains infinite stiffness against static direct disturbance even if such a spring is added. The characteristics to dynamic direct disturbances are also studied experimentally.
  Japanese
  ISSN：0387-5024, CiNii Articles ID：120006385118
• Flux Path Control Magnetic Suspension : Development of a System Using Voice Coil Motors　　　　　　　　　　　　　　　
  水野 毅; 平井 雄三; 石野 裕二; 高崎 正也
  日本機械学會論文集. C編, Volume：72, Number：721, First page：2869, Last page：2876, 2006, [Reviewed]
  A novel magnetic suspension system with three flux path control modules was developed. The module consists of a ferromagnetic plate, a voice coil motor (VCM) for driving the plate and a displacement sensor for detecting the position of the plate; the sensor is comprised of a V-shape plate spring and four strain guages pasted on it. The ferromagnetic plate is inserted into the gap between a permanent magnet and a suspended object (floator). The lateral position of the plate is controlled with the VCM and the sensor. Since the flux from the permanent magnet to the floator varies according to the position, the amplitude and direction of the attractive force acting on the floator can be adjusted by using multiple modules. Stable suspension was achieved by applying PD control. A fluctuation was observed in the position of the floator. It was reduced by feeding back the lateral motions of the floator. The two- or three-dimensional noncontact manipulation of the floator was also achieved in the developed magnetic suspension system.
  社団法人日本機械学会, Japanese
  ISSN：0387-5024, CiNii Articles ID：120006385122
• Velocity Control of Surface Acoustic Wave Linear Motor Using PWM　　　　　　　　　　　　　　　
  小谷 浩之; 高崎 正也; 石野 裕二; 水野 毅
  日本機械学會論文集. C編, Volume：72, Number：722, First page：3236, Last page：3241, 2006, [Reviewed]
  Surface acoustic wave (SAW) linear motor is a kind of ultrasonic motors. The SAW linear motor has several advantages, such as thin structure, high thrust force, high velocity and precise positioning. Relationship between applied voltage and output velocity, however, had non-linearity in low velocity range due to friction drive principle. Therefore the SAW linear motor cannot obtain stable driving without feedback control at low velocity. To realize low velocity, PWM (pulse width modulation) control and flexible slider structure are employed. The flexible structure is installed to cancel vibration due to PWM carrier frequency. In this research, PWM is applied for controlling the slider velocity. Lower velocity in non-linear range is realized. Influence of the flexible structure upon precise positioning is investigated.
  社団法人日本機械学会
  ISSN：0387-5024, CiNii Articles ID：120006385125
• Self-Sensing Magnetic Suspension Using an H-bridge Type Hysteresis Amplifier Operating in Two Quadrants　　　　　　　　　　　　　　　
  MIZUNO Takeshi; HIRASAWA Yuji; TAKASAKI Masaya; ISHINO Yuji
  計測自動制御学会論文集, Volume：41, Number：5, First page：459, Last page：465, May 2005, [Reviewed]
  計測自動制御学会, English
  ISSN：0453-4654, CiNii Articles ID：10015728532
• Vibration isolation system using zero-power magnetic suspension with a weight suspension mechanism　　　　　　　　　　　　　　　
  Takeshi Mizuno; Daisuke Kishita; Md. Emdadul Hoque; Masaya Takasaki; Yuji Ishino
  IFAC Proceedings Volumes (IFAC-PapersOnline), Volume：16, First page：61, Last page：66, 2005
  Vibration isolation system using zero-power magnetic suspension is modified to be equipped with a weight support mechanism. The original system has a problem that the whole weight of the isolation table must be supported solely by the attractive force produced by permanent magnets. It is an obstacle to develop large isolation tables. in order to overcome this obstacle, a weight support mechanism is introduced in parallel with the serial connection of a zero-power magnetic suspension system and a normal spring. It can reduce the static load force that the zero-power magnetic suspension has to support. The basic characteristics of the modified system are shown analytically. Experimental study demonstrates that the modified system maintains infinite stiffness against direct disturbance even if such a weight support mechanism is added. Copyright © 2005 IFAC.
  IFAC Secretariat, English, International conference proceedings
  DOI：https://doi.org/10.3182/20050703-6-cz-1902.01222
  DOI ID：10.3182/20050703-6-cz-1902.01222, ISSN：1474-6670, SCOPUS ID：79960723697
• Transparent surface acoustic wave tactile display　　　　　　　　　　　　　　　
  Masaya Takasaki; Hiroyuki Kotani; Takeshi Mizuno; Takaaki Nara
  2005 IEEE/RSJ International Conference on Intelligent Robots and Systems, IROS, First page：1115, Last page：1120, 2005, [Reviewed]
  We have already proposed a novel method to provide human tactile sensation using surface acoustic wave (SAW). A pulse modulated driving voltage excites temporal distribution of standing SAW. The distribution generates friction shift on the surface of a SAW substrate. When the surface with the burst SAW is explored, the friction shift can be perceived as tactile sensation at mechanoreceptors in the finger skin. Controlling the burst frequency according to measured rubbing motion, reality of the displayed sensation can be enhanced. In this research, we proposed a transparent tactile display. An experimental apparatus was fabricated on trial and controlled by using captured images. The apparatus demonstrated potentiality of the tactile display for various applications. © 2005 IEEE.
  English, International conference proceedings
  DOI：https://doi.org/10.1109/IROS.2005.1545129
  DOI ID：10.1109/IROS.2005.1545129, SCOPUS ID：79957995279
• Pneumatic three-axis vibration isolation system using negative stiffness　　　　　　　　　　　　　　　
  Takeshi Mizuno; Masato Murashita; Masaya Takasaki; Yuji Ishino
  Proceedings of the 44th IEEE Conference on Decision and Control, and the European Control Conference, CDC-ECC '05, Volume：2005, First page：8254, Last page：8259, 2005, [Reviewed]
  A three-axis active vibration isolation system with pneumatic actuators for generating negative stiffness was developed. A control method of realizing a suspension with negative stiffness by the actuator was derived. It was implemented in the developed system where each actuator was controlled locally. It was demonstrated experimentally that the equalization of the amplitude of negative and positive stiffness enables the system to have zero compliance to direct disturbance. © 2005 IEEE.
  English, International conference proceedings
  DOI：https://doi.org/10.1109/CDC.2005.1583498
  DOI ID：10.1109/CDC.2005.1583498, SCOPUS ID：33847200471
• Mass Measurement Using a System Containing an On-Off Relay with Dead Zone　　　　　　　　　　　　　　　
  MIZUNO Takeshi; TAKEUCHI Minoru; TAKASAKI Masaya; ISHINO Yuji
  計測自動制御学会論文集, Volume：41, Number：1, First page：25, Last page：30, Jan. 2005, [Reviewed]
  計測自動制御学会, English
  ISSN：0453-4654, CiNii Articles ID：10014324136
• Pneumatic Active Vibration Isolation Systems Using Negative Stiffness　　　　　　　　　　　　　　　
  MIZUNO Takeshi; MURASHITA Masato; TAKASAKI Masaya; ISHINO Yuji
  Transactions of the Society of Instrument and Control Engineers, Volume：41, Number：8, First page：676, Last page：684, 2005, [Reviewed]
  This paper investigates the applicability of pneumatic actuator to active vibration isolation system using negative stiffness. First, a control method of realizing negative stiffness with an pneumatic actuator is derived based on a single-degree-of-freedom model. Its efficacy is verified in a fabricated single-axis apparatus. Then a zero-compliance mechanism is realized by connecting a suspension with negative stiffness and a suspension with positive stiffness; both the suspensions use fabricated pneumatic actuators. Next, such zero-compliance mechanism was also achieved in a developed three-axis active vibration isolation system using the pneumatic actuators. The dynamic characteristics of the system to direct disturbance were estimated experimentally.
  公益社団法人 計測自動制御学会
  ISSN：0453-4654, CiNii Articles ID：130003971487
• Design of a mode-based controller for 3-DOF vibration isolation system　　　　　　　　　　　　　　　
  Md. Emdadul Hoque; Masaya Takasaki; Yuji Ishino; Takeshi Mizuno
  2004 IEEE Conference on Robotics, Automation and Mechatronics, First page：478, Last page：483, 2004
  This paper presents an active suspension technique for a three-degrees-of-freedom (3-DOF) vibration isolation system using negative stiffness. A mode-based digital controller is designed based on a theoretical model to generate negative stiffness by active suspension. The active suspension mechanism, in conjunction with a conventional spring in series, can generate infinite stiffness against direct disturbances on the isolation table. Three-axis motions of the isolation table in the vertical directions are actively controlled by the proposed system. Experimental results show that the active suspension system using the proposed controller well evaluates and describes the zero-compliance against direct disturbances.
  English, International conference proceedings
  SCOPUS ID：11244254189
• Vibration Isolation System Using Negative Stiffness　　　　　　　　　　　　　　　
  MIZUNO Takeshi; TOUMIYA Takefumi; TAKASAKI Masaya
  JSME International Journal Series B Fluids and Thermal Engineering, Volume：46, Number：3, First page：807, Last page：812, Sep. 2003
  A new vibration isolation system using negative stiffness realized by active control technique is proposed in this paper. The serial connection of a normal spring and a suspension system with negative stiffness enables the isolation system to have low stiffness for vibration from the ground and high (theoretically infinite) stiffness against direct disturbance acting on the isolation table. A control method of realizing negative stiffness with a linear actuator is presented in an analytical form. The validity of this method is confirmed experimentally with an apparatus equipped with a voice coil motor. It is also confirmed experimentally that high stiffness against direct disturbance on the isolation table can be achieved in the proposed vibration isolation system.
  The Japan Society of Mechanical Engineers, English
  DOI：https://doi.org/10.1299/jsmec.46.807
  DOI ID：10.1299/jsmec.46.807, ISSN：1344-7653, CiNii Articles ID：110004155652, CiNii Books ID：AA11179487
• Development of a Three-Axis Active Vibration Isolation System Using Zero-Power Magnetic Suspension　　　　　　　　　　　　　　　
  Takeshi Mizuno; Hirohisa Suzuki; Masaya Takasaki; Yuji Ishino
  Proceedings of the IEEE Conference on Decision and Control, Volume：5, First page：4493, Last page：4498, 2003
  A three-axis active vibration isolation system using zero-power magnetic suspension was developed. A mathematical model of the apparatus was derived for discussing the control system. It was shown that the three motions could be treated separately and, in addition, each dynamics was represented in a similar form. The condition for the system to have infinite stiffness for direct disturbance was derived. This characteristic was confirmed experimentally. It was also demonstrated that the transmissibility characteristics from the floor to the isolation table were not worsened by introducing zero-power control.
  English, International conference proceedings
  ISSN：0191-2216, SCOPUS ID：1542290101
• A surface acoustic wave tactile display with friction control　　　　　　　　　　　　　　　
  M Takasaki; T Nara; S Tachi; T Higuchi
  14TH IEEE INTERNATIONAL CONFERENCE ON MICRO ELECTRO MECHANICAL SYSTEMS, TECHNICAL DIGEST, First page：240, Last page：243, 2001, [Reviewed]
  We proposed a novel method to provide human tactile sensation using surface acoustic wave (SAW). A pulse modulated driving voltage excites temporal distribution of standing SAW. The distribution generates alternative friction shift on the surface of SAW substrate. When the surface with burst SAW is explored, the friction shift can be perceived as tactile sensation at mechanoreceptors in the finger skin. We analyzed a sliding motion of a finger on a rough solid surface and fabricated a prototype, which could express roughness successfully.
  IEEE, English, International conference proceedings
  ISSN：1084-6999, Web of Science ID：WOS:000166833600059
• Surface Acoustic Wave (SAW) tactile display based on properties of mechanoreceptors　　　　　　　　　　　　　　　
  T Nara; M Takasaki; T Maeda; T Higuchi; S Ando; S Tachi
  IEEE VIRTUAL REALITY 2001, PROCEEDINGS, First page：13, Last page：20, 2001, [Reviewed]
  In this paper, we first analyze dynamic properties of rapidly adapting mechanoreceptors in order to derive a principle of tactile displays. It is shown that Meissner corpuscles with coiled axons and Pacinian corpuscles with layered lamellae are suited to detect equivoluminal distortion of a skin. Combining these analyses with a model of a contact and a relative motion between an object and the skin, it is shown that a prerequisite for tactile displays is to generate sources of shear stress that can be spatially dispersed at the skin surface and temporally modulated with a stick-slip frequency determined by parameters of the object to be displayed. As a device that satisfys this prerequisite, we propose a tactile display using Surface Acoustic Waves(SAW). The roughness of the surface can be changed continuously by controlling the burst frequency of the SAW.
  IEEE COMPUTER SOC, English, International conference proceedings
  ISSN：1087-8270, Web of Science ID：WOS:000168102100004
• An application of SAW to a tactile display in virtual reality　　　　　　　　　　　　　　　
  Takaaki Nara; Masaya Takasaki; Susumu Tachi; Toshiro Higuchi
  Proceedings of the IEEE Ultrasonics Symposium, Volume：1, First page：1, Last page：4, 2000
  SAW has great potential for a 'tactile display' in virtual reality which provides a human virtually with varied tactile sensation of roughness, textures, and friction. From an analysis of a sliding motion of a finger on a rough surface, it is shown that the parameters of the grain are directly related to a frequency of a stick-slip vibration of friction. Thus, it is necessary for the tactile display to create dispersed sources of shear stress which can be modulated temporally with the stick-slip frequency. In our tactile display, we explore a LiNbO3 128° Y-cut substrate with a 'slider' which has around 100 steel balls with the diameter of 800[μm] on a thin tape. Because friction between the substrate and the slider is reduced by generating SAW on the substrate, a virtual stick-slip can be created by a burst standing SAW with the carrier frequency of 15[MHz]. It is confirmed that the variable grain can be represented by controlling the burst frequency of SAW.
  International conference proceedings
  Scopus：https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=0034579987&origin=inward
  Scopus Citedby：https://www.scopus.com/inward/citedby.uri?partnerID=HzOxMe3b&scp=0034579987&origin=inward
  ISSN：1051-0117, SCOPUS ID：0034579987
• A tactile display using surface acoustic wave　　　　　　　　　　　　　　　
  M Takasaki; T Nara; S Tachi; T Higuchi
  IEEE RO-MAN 2000: 9TH IEEE INTERNATIONAL WORKSHOP ON ROBOT AND HUMAN INTERACTIVE COMMUNICATION, PROCEEDINGS, First page：364, Last page：367, 2000, [Reviewed]
  We propose a novel method to provide human tactile sensation using surface acoustic wave (SAW). A pulse modulated driving voltage excites temporal distribution of shear force or friction shift on the surface of SAW substrate. The force / friction distribution can be perceived as tactile sensation at mechanoreceptors in the finger skin. A first prototype could express roughness successfully.
  IEEE, English, International conference proceedings
  Web of Science ID：WOS:000166835900065
• Surface acoustic wave gyro sensor　　　　　　　　　　　　　　　
  Minoru Kurosawa; Yoshimitsu Fukuda; Masaya Takasaki; Toshiro Higuchi
  International Conference on Solid-State Sensors and Actuators, Proceedings, Volume：2, First page：863, Last page：866, 1997
  This paper explains a novel method to measure an angular velocity by using a surface acoustic wave device. Coriolis forces act on the particles vibrating in the standing wave of the surface acoustic wave, but cancel one another. Distributed cyclic perturbation masses on the surface realize detection of angular velocity. At the mass, the secondary SAW which have some coherence can be built up in the orthogonal direction of the primary standing wave. This novel gyro sensor was planned based on this principle. The optimization of the electrodes dimensions was carried out by equivalent circuit analysis. The SAW gyro sensor using the Rayleigh wave which would propagate on a 128° Y-cut LiNbO3 3-inches wafer with operating frequency of 15MHz was designed.
  IEEE, English, International conference proceedings
  SCOPUS ID：0030655642

• Research on airborne non-contact rotation mechanism using ultrasonic transducers and rotating block-2nd Report: application of reflected wave-　　　　　　　　　　　　　　　
  萩生駿壱; 石野裕二; 水野毅; 長谷川圭介; 高崎正也
  電磁力関連のダイナミクスシンポジウム講演論文集, Volume：36th (CD-ROM), 2024
  J-Global ID：202502228703251103
• Evaluation of cutting efficiency of ultrasonic dental scaler: Third report: Influence of tip pressing angle　　　　　　　　　　　　　　　
  三浦蓮太郎; 水野毅; 石野裕二; 長谷川圭介; 高崎正也
  電磁力関連のダイナミクスシンポジウム講演論文集, Volume：36th (CD-ROM), 2024
  J-Global ID：202502231071445767
• Characteristics of magnetic suspension system with rotational flux-path control mechanism　　　　　　　　　　　　　　　
  後山翔; 水野毅; 長谷川圭介; 石野裕二; 高崎正也
  電磁力関連のダイナミクスシンポジウム講演論文集, Volume：36th (CD-ROM), 2024
  J-Global ID：202502256317200887
• Application of pumps with the ultrasonic transducer and opposing block to liquid~Second report: Investigation of performance improvement by new block shapes~　　　　　　　　　　　　　　　
  石田慎義; 長谷川圭介; 石野裕二; 水野毅; 高崎正也
  電磁力関連のダイナミクスシンポジウム講演論文集, Volume：36th (CD-ROM), 2024
  J-Global ID：202502273702993210
• Fabrication of ultrasonic transducer usable in high magnetic field and driving tests　　　　　　　　　　　　　　　
  多田良知; 高崎正也; 水野毅; 石野裕二; 長谷川圭介; 原正之; 大西秀明; 大鶴直史; 児玉直樹; 櫻井典子
  日本機械学会ロボティクス・メカトロニクス講演会講演論文集(CD-ROM), Volume：2024, 2024
  ISSN：2424-3124, J-Global ID：202502257069397449
• Development of Air Chamber in Airbag made by polyimide for Smallest Moon Lander OMOTENASHI　　　　　　　　　　　　　　　
  石野裕二; 山口大介; 大槻真嗣; 高橋洋介; 佐藤亮; 高崎正也; 水野毅
  日本機械学会運動と振動の制御シンポジウム論文集(CD-ROM), Volume：16th, 2019
  ISSN：2424-3000, J-Global ID：202102281857160129
• 複雑形状を有するポリイミド製空気室の製作と回転型モータの試作　　　　　　　　　　　　　　　
  山口 大介; 永見 僚; 石野 裕二; 髙﨑 正也; 水野 毅
  Volume：2019, Number：0, First page：341, Last page：341, 2019
  

  ポリイミド（PI）フィルム製空気室を駆動源に用いた空圧モータの試作を行った．空気室は複数の凸形状を成型したPIフィルムを形状に合わせて溶着することで製作される．従来のPIフィルム同士の溶着では，加熱した金型をごく短時間押し付けることで溶着を実現していたが，形状に合わせた溶着が困難であった．そこで本発表では，試作している複雑な形状を有するPIフィルムに対する溶着手法と空圧モータについて述べる．

  
  Japanese
  DOI：https://doi.org/10.11522/pscjspe.2019A.0_341
  DOI ID：10.11522/pscjspe.2019A.0_341, CiNii Articles ID：130007800930
• 視線操作による周辺視の度合いがラバーハンド錯覚に及ぼす影響　　　　　　　　　　　　　　　
  國松勇希; 原正之; 岡本正吾; 金山範明; 三木将仁; 高崎正也; 水野毅
  計測自動制御学会システムインテグレーション部門講演会(CD-ROM), Volume：19th, First page：ROMBUNNO.1B3‐02, 13 Dec. 2018
  Japanese
  J-Global ID：201902267226536367
• ポリイミド溶着技術を応用した月面着陸用エアバック気室の改良　　　　　　　　　　　　　　　
  高橋洋介; 山口大介; 佐藤亮; 石野裕二; 大槻真嗣; 高崎正也; 水野毅
  Volume：2018, 2018
  J-Global ID：201802248518861172
• Pressurization test of polyimide air chamber aimed at lunar landing airbag　　　　　　　　　　　　　　　
  Yamaguchi Daisuke; Takahashi Yosuke; Sato Ryo; Ishino Yuji; Otsuki Masatsugu; Yoshimitsu Tetsuo; Yoshikawa Kento; Hara Masayuki; Takasaki Masaya; Mizuno Takeshi
  Proceedings of JSPE Semestrial Meeting, Volume：2017A, First page：743, Last page：744, 2017
  NASAのロケットシステムSLSに相乗りするCubeSatの一つとして，超小型月面技術実証機OMOTENASHIの開発が進められている．OMOTENASHIではソフトランディングが行えないため，月面との衝突緩和を目的としてエアバッグの使用が提案されている．本発表では，エアバッグへの使用を検討しているポリイミドフィルム製空気室の構造と基礎特性について述べる．
  The Japan Society for Precision Engineering, Japanese
  DOI：https://doi.org/10.11522/pscjspe.2017a.0_743
  DOI ID：10.11522/pscjspe.2017a.0_743, CiNii Articles ID：130006434599
• On switching stiffness control in partially active magnetic bearings　　　　　　　　　　　　　　　
  水野 毅; 石野 裕二; 髙崎 正也; 原 正之; 山口 大介
  Volume：2016, Number：97, First page：99, Last page：103, 01 Dec. 2016
  Japanese
  CiNii Articles ID：40021058228, CiNii Books ID：AA12475827
• Frequency Characteristic of Surface Acoustic Wave Tactile Display　　　　　　　　　　　　　　　
  佐藤 史樹; 山口 大介; 原 正之; 高崎 正也; 石野 裕二; 水野 毅
  Volume：115, Number：512, First page：11, Last page：14, 18 Mar. 2016
  Japanese
  ISSN：0913-5685, CiNii Articles ID：40020792731, CiNii Books ID：AN10487237
• Vibration Control by Varying Stiffness in Passive Magnetic Suspension Mechanism　　　　　　　　　　　　　　　
  水野 毅; 髙﨑 正也; 石野 裕二
  Volume：2015, Number：117, First page：13, Last page：16, 21 Nov. 2015
  Japanese
  CiNii Articles ID：40020662388, CiNii Books ID：AA12475827
• G1000205 Development of Three-Axis Flux-Path Control Magnetic Suspension System Using Flux Concentration　　　　　　　　　　　　　　　
  MIZUNO Takeshi; SUGAWARA Yosuke; ISHINO Yuji; TAKASAKI Masaya
  Mechanical Engineering Congress, Japan, Volume：2015, First page："G1000205, Last page：1"-"G1000205-4", 13 Sep. 2015
  A flux-path magnetic suspension system was fabricated in which the three-degree-of-freedom motions of the floator was actively controlled. In this system, a control plate with four rectangular permanent magnets for magnetic concentration were used instead of ferromagnetic control plates in the conventional flux-path magnetic suspension system to increase the suspension force. The three-degree-of-freedom motions of the control plate were controlled with four differential electromagnetic actuators according to the motions of the floator. Contactless suspension was achieved by applying PD control in the fabricated suspension system.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110010048477, CiNii Books ID：AA12588255
• 超音波支持 (特集 超音波によるアクチュエーション技術(1))　　　　　　　　　　　　　　　
  髙﨑 正也
  Volume：27, Number：5, First page：13, Last page：17, Sep. 2015
  Japanese
  ISSN：0916-2410, CiNii Articles ID：40020602005, CiNii Books ID：AN10068970
• 443 Development of 3-component Force Measurement Apparatus Using Zero-compliance mechanism : 1st report: Basic Concepts and Fabrication of Measurement Device　　　　　　　　　　　　　　　
  IIDA Keisuke; MIZUNO Takeshi; TAKASAKI Masaya; ISHINO Yuji; YAMAGUCHI Daisuke; HARA Masayuki
  Dynamics and Design Conference : D & D, Volume：2015, First page："443, Last page：1"-"443-7", 25 Aug. 2015
  Zero-compliance mechanism is applied to micro-force measurement. The system makes it possible to estimate the force from the displacement of a detection point without displacing the point of force. The efficacy was proved by an experimental apparatus uses a parallel springs and a voice coil motor as an actuator. However, the accuracy of measurement was limited because of independent four single-axis measurement units. To solve such a problem, a structurally-integrated measurement unit to is developed. In this work, an apparatus for 3-component force measurement is designed and fabricated.
  The Japan Society of Mechanical Engineers, Japanese
  ISSN：1348-0235, CiNii Articles ID：110010054212, CiNii Books ID：AA11901770
• 214 Study on AC Magnetic Suspension Using Magnetic Resonant Coupling : 4th report: Evaluation of Suspension Characteristics　　　　　　　　　　　　　　　
  KORIKAWA Tomoyuki; MIZUNO Takeshi; TAKASAKI Masaya; ISHINO Yuji; HARA Masayuki; YAMAGUCHI Daisuke
  Dynamics and Design Conference : D & D, Volume：2015, First page："214, Last page：1"-"214-6", 25 Aug. 2015
  The characteristics of the AC magnetic suspension system using magnetic resonant coupling are studied experimentally. The treated suspension system has self-stabilization characteristics so that noncontact suspension can be achieved without any active control. An experimental apparatus has been fabricated which has three pairs of primary and secondary electromagnets for three-axis suspension; the three primary electromagnets are fixed to the stator, and the three secondary electromagnets are fixed to the floator. Stable noncontact suspension has been achieved by supporting the stator through springs and dampers from the base. The characteristics of the achieved suspension system are studied experimentally.
  The Japan Society of Mechanical Engineers, Japanese
  ISSN：1348-0235, CiNii Articles ID：110010051810, CiNii Books ID：AA11901770
• B202 Lateral Vibration Control in Attractive Magnetic Suspension System : 2nd report: Experimental study on the lateral vibration control　　　　　　　　　　　　　　　
  MIZUNO Takeshi; TANABE Jun; ISHINO Yuji; TAKASAKI Masaya
  Dynamics and Design Conference, Volume：2015, Number：14, First page：281, Last page：284, 22 Jun. 2015
  A switching stiffness control was applied to reduce vibration in the lateral directions in active magnetic suspension system with electromagnets operated in the differential mode. The magnetic suspension system using the attractive force between magnetized bodies is inherently unstable in the normal direction so that feedback control is necessary to achieve stable suspension. In contrast, it is usually stable in the lateral directions because of the edge effects in the magnetic circuits. However, damping in the lateral directions is poor so that vibration is easily induced. In this work, a switching stiffness control was applied to attenuate such vibration. The effectiveness of the switching stiffness control was confirmed experimentally. In addition, a modified control method that varies stiffness continuously was proposed to overcome problems occurring in switching. The efficacy of the modified control method was also confirmed experimentally.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110010050252, CiNii Books ID：AA11902241
• 20210 Study on AC Magnetic Suspension Using Magnetic Resonant Coupling : 3rd report: Realization of Noncontact Suspension　　　　　　　　　　　　　　　
  KORIKAWA Tomoyuki; ISHINO Yuji; TAKASAKI Masaya; MIZUNO Takeshi
  Volume：2015, Number：21, First page："20210, Last page：1"-"20210-2", 20 Mar. 2015
  AC Magnetic suspension system using magnetic resonant coupling has been proposed which has the performance of noncontact energy transfer to the suspended object (floator). This system has the self-stabilization property so that passive suspension is possible. In this paper, an experimental apparatus is fabricated which has three pairs of primary and secondary electromagnets for three-axis suspension; three primary electromagnets are fixed to the stator, and three secondary electromagnets are fixed to the floator. The floator is successfully suspended without any mechanical contact. Stable suspension is achieved by supporting the stator through springs and dampers.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110009948298, CiNii Books ID：AA11902161
• Development of Prototype Pen Tablet Type Tactile Display Using Stylus with Built-in Ultrasonic Transducer　　　　　　　　　　　　　　　
  HASEBE Kazuhiko; ISHINO Yuji; HARA Masayuki; YAMAGUCHI Daisuke; TAKASAKI Masaya; MIZUNO Takeshi
  Technical report of IEICE. HIP, Volume：114, Number：483, First page：11, Last page：14, 02 Mar. 2015
  When rubbing an object surface like wood or paper with stylus, we can feel tactile sensation such as rough feeling through a stylus. For presenting the sensation, pen tablet interface using surface acoustic wave tactile display has been proposed. The display has difficulty in expanding the presentation area since a single crystal of lithium niobate is used as the display and the manufacture of large one is difficult. In this research, pen tablet type tactile display using a stylus with built-in ultrasonic transducer which is based on the same principle is prototyped.
  The Institute of Electronics, Information and Communication Engineers, Japanese
  ISSN：0913-5685, CiNii Articles ID：110010022154, CiNii Books ID：AN10487237
• 2P4-7 Pump Effect by Ultrasonic Transducer and Opposing Surface(Poster Session)　　　　　　　　　　　　　　　
  Shinada Hiroaki; Ishino Yuji; Yamaguchi Daisuke; Takasaki Masaya; Mizuno Takeshi
  Proceedings of Symposium on Ultrasonic Electronics, Volume：35, First page：299, Last page：300, 03 Dec. 2014
  Steering committee of symposium on ultrasonic electronics, English
  ISSN：1348-8236, CiNii Articles ID：110009981215, CiNii Books ID：AA1240726X
• 1D15 Realization of diamagnetic levitation of column-shaped graphite(The 12th International Conference on Motion and Vibration Control)　　　　　　　　　　　　　　　
  IIDA Keisuke; NARISAWA Yoshinori; ISHINO Yuji; TAKASAKI Masaya; MIZUNO Takeshi
  Dynamics and Design Conference, Volume：2014, Number：12, First page："1D15, Last page：1"-"1D15-9", 03 Aug. 2014
  The completely passive levitation of a column-shaped graphite object is achieved. Graphite is a typical diamagnetic material. Diamagnetic materials have a property of generating repulsive force in magnetic field. Most diamagnetic levitation systems use high-oriented pyrolytic graphite (PG) sheets because sufficient force for levitation is obtained easily. In contrast, a column-shaped graphites are the target of levitation in this work. Experimental apparatus for diamagnetic levitation is fabricated. The apparatus uses a two-dimensional Halbach array made of cubic neodymium magnets. The magnetic fields in the apparatus are analyzed numerically and measured for comparison. It is shown that the stable diamagnetic levitation of a column-shaped graphite is achieved. The floator is fabricated by combining the pencil leads made of graphite. The diamagnetic forces acting on the floator are measured. In addition, the effects of anisotropy of graphite on the levitation characteristics are discussed.
  The Japan Society of Mechanical Engineers, English
  CiNii Articles ID：110009976539, CiNii Books ID：AA11902241
• 1D25 Mass Measurement Using the Fixed-Point of a Spring-Mass System with a Dynamic Vibration Absorber and an Inertial-Mass Vibrator(The 12th International Conference on Motion and Vibration Control)　　　　　　　　　　　　　　　
  KORIKAWA Tomoyuki; ISHINO Yuji; TAKASAKI Masaya; MIZUNO Takeshi
  Dynamics and Design Conference, Volume：2014, Number：12, First page："1D25, Last page：1"-"1D25-12", 03 Aug. 2014
  A mass-spring system with a dynamic vibration absorber has a fixed point in its frequency response curves. A method of measuring mass using this property was proposed. It has an advantage that mass is estimated independently of the damping in the absorber. The developed system was characterized by using a phase-looked loop to achieve the tuning condition. However, because the actuator producing the harmonic force was mounted on the base, the reaction force was transmitted to the surrounding structure. It may cause a severe vibration of the surrounding structure. Therefore, it is necessary to prevent transmission of force to the surrounding structure in measuring. In this paper, a new type of mass measurement system is proposed which uses an inertial-mass vibrator to reduce the transmitted vibration. The tuning conditions are derived for both systems with a damped absorber and with an undamped absorber. The principles of measurement are described based on a mathematical model. An experimental apparatus is designed and fabricated. The efficacy of the measurement system with an inertial mass-type vibrator is studied both analytically and experimentally.
  The Japan Society of Mechanical Engineers, English
  CiNii Articles ID：110009976544, CiNii Books ID：AA11902241
• 1P1-J05 Tactile Display Using Sheet-like Ultrasonic Transducer : 4st report Valuation of Couplant for Sheet-Like Transducer(Tactile and Force Sensing (1))　　　　　　　　　　　　　　　
  SATO Daiki; TAKASAKI Masaya; MIZUNO Takeshi; ISHINO Yuji
  Volume：2014, First page："1P1, Last page：J05(1)"-"1P1-J05(2)", 24 May 2014
  Recently, the touch panel has been widespread as computer interface. Using the touch panel is easy because of intuitive operation, but it is difficult for a visually impaired person who cannot get the visual information. In order to improve this problem, tactile display using sheet-like ultrasonic transducer has been developed in previous research. By this device, when a touch panel is operated, user can get tactile feedback, and it is possible to recognize an icon and a window. However, at the present stage, it cannot be mounted on a large-sized touch panel. So, we aim at development of tactile display using sheet-like transducer which can be mounted on a large-sized touch panel. In this paper, evaluation of the couplant used for the sheet-like ultrasonic transducer is reported.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110009966715, CiNii Books ID：AA11902933
• 20704 Diamagnetic Levitation of an Object Consisting of Pencil Leads　　　　　　　　　　　　　　　
  NARISAWA Yoshinori; AKIYAMA Tomohiro; MIZUNO Takeshi; TAKASAKI Masaya; ISHINO Yuji
  Volume：2014, Number：20, First page："20704, Last page：1"-"20704-2", 14 Mar. 2014
  The completely passive levitation of a special-shaped graphite object is achieved. Graphite is a typical diamagnetic material. Because the diamagnetic materials have a property of causing repulsive force in magnetic field, it can be stabilized with a set of permanent magnets. Most recently reported diamagnetic levitation systems use high oriented pyrolytic graphite sheets because enough force for levitation is obtained easily. In contrast, this work targets objects with different shapes such as spherical or cylindrical. This paper presents several examples of the design and analysis of magnetic field produced by permanent magnetic and ferromagnetic materials. It is also shown that the stable diamagnetic levitation of pencil leads is achieved by the fabricated magnetic stator.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110009949444, CiNii Books ID：AA11902161
• 20917 Active Vibration Isolation System with an Active Dynamic Vibration Absorber : 5th report: Realization of Acceleration Feedback by Combining MEMS-Sensed Signal　　　　　　　　　　　　　　　
  SEKIYA Hiroaki; MIZUNO Takeshi; TAKASAKI Masaya; ISHINO Yuji
  Volume：2014, Number：20, First page："20917, Last page：1"-"20917-2", 14 Mar. 2014
  An active vibration isolation system has been proposed that uses an active dynamic absorber as a servo-accelerometer in a low frequency range and a vibration control device in a high frequency range. Complimentarily, it uses an air actuator as a control device in a low frequency range and a low cost accelerometer as a sensing device in a high frequency range. It aims to develop a high performance active vibration isolation system that is lower in cost than conventional active vibration system. This report shows the effects of acceleration feedback by combining MEMS-sensed signal compared with acceleration feedback by combining servo-accelerometer signal.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110009949480, CiNii Books ID：AA11902161
• 10702 Compensation for Unbalance Using Exogenous Signal Synchronized with Rotation to a Rotary Gyro with Hybrid Suspension　　　　　　　　　　　　　　　
  AKIYAMA Tomohiro; MIZUNO Takeshi; TAKASAKI Masaya; ISHINO Yuji
  Volume：2014, Number：20, First page："10702, Last page：1"-"10702-2", 14 Mar. 2014
  This paper presents an application of unbalance compensation for unbalance using exogenous signal synchronized with rotation to a rotary gyro with hybrid suspension. In this gyro, a disk-type rotor is connected to a synchronous motor through a fluid bearing and the motor is fixed to the frame of the floator. The four-degree-of-freedom motions of the floator are constrained by a cross spring and a gimbal. The two rotational motions of the floator are controlled by four electromagnets. Such hybrid suspension makes the system less damped. Therefore, high-accuracy measurement is possible by this gyro. However, one of the problems is that an oscillating component due to unbalance appears in the estimated angular velocity because the estimation is based on the control currents for regulating the relative displacement of the rotor to the stator. To solve this problem, unbalance compensation is applied to remove the oscillating component. It is confirmed experimentally that the estimated signal agrees well with the reference signal.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110009949303, CiNii Books ID：AA11902161
• 10703 Microforce Measurement Using a Zero-compliance Mechanism : 3rd report: Discussion about the measurement frequency range　　　　　　　　　　　　　　　
  TAKABAYASHI Atsushi; MIZUNO Takeshi; ISHINO Yuji; Takasaki Masaya
  Volume：2014, Number：20, First page："10703, Last page：1"-"10703-2", 14 Mar. 2014
  A zero-compliance mechanism is applied to force measurement. In the proposed force measurement system, the force is estimated from the displacement of a detection point without displacing the point of force. The efficacy was demonstrated by an experimental apparatus using series magnetic suspension. Because the apparatus used magnetic force to achieve zero-compliance, the accuracy of measurement was limited because of the nonlinearity. To solve such a problem, a single-axis measurement unit has been developed which uses a parallel spring and a voice coil motor as an actuator. In this paper, the control system is designed based on the pole assignment method. The relation between the closed-loop poles and the measurement bandwidth is investigated experimentally.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110009949304, CiNii Books ID：AA11902161
• B14 Examination of Difference of Dummy Fingers for Tele-touch System　　　　　　　　　　　　　　　
  SATO Daiki; ISHINO Yuji; TAKASAKI Masaya; MIZUNO Takeshi
  Dynamics and Design Conference, Volume：2013, Number：13, First page："B14, Last page：1"-"B14-7", 25 Aug. 2013
  In recent years, exchanging the large amount of accurate information is required. Various tactile display has been investigated as the method of informing tactile sensation, which is one of the five senses. Tactile display using surface acoustic wave (SAW) has been studied, and Tele-touch system on tactile sensation during rubbing physical surface has been also proposed. In this system, dummy finger is proposed as tactile sensor where the dynamical vibration of the dummy skin is transformed to electrical signal while the finger is exploring on the physical surface. These dummy fingers were fabricated to simulate human finger as for their structure, form and hardness. However, vibration transmitted to the dummy finger is different in rubbing on physical surface, because each dummy finger has different stiffness and dumping. In this paper, dynamical model of the dummy finger and their different characteristic are studied for establish of Tele-touch system.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110009976190, CiNii Books ID：AA11902241
• B09 Development of Self-Spinning Floator for Wind-Tunnel Using Magnetic Suspension　　　　　　　　　　　　　　　
  JIBIKI Yonosuke; MIZUNO Takeshi; TAKASAKI Masaya; ISHINO Yuji
  Dynamics and Design Conference, Volume：2013, Number：13, First page："B09, Last page：1"-"B09-10", 25 Aug. 2013
  A wind-tunnel system for spinning body has been proposed to measure aerodynamic forces acting on the body. In the proposed system, the body is suspended and rotated by electromagnets. The forces are measured from the control signal for suspension. Three-dimensional positioning and rotation of the body were achieved. However, due to the non-uniformity of the magnetic fields, the rotation around a horizontal axis suffered from drag torque caused by eddy current. In this paper, a self-spinning floating body with a function of adjusting the angle of the spinning axis is developed. The floator was suspended successfully with spinning around various axes.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110009976185, CiNii Books ID：AA11902241
• B11 Development of a 2-DOF Active Magnetically Suspended Micro Gyro : 1st report:Basic Concepts and Measurement Principle　　　　　　　　　　　　　　　
  AKIYAMA Tomohiro; MIZUNO Takeshi; TAKASAKI Masaya; ISHINO Yuji
  Dynamics and Design Conference, Volume：2013, Number：13, First page："B11, Last page：1"-"B11-8", 25 Aug. 2013
  A new configuration for rotating gyros using magnetic suspension is proposed in this study. Gyro is one of inertial sensor and measuring instrument for angular velocity. In a magnetically suspended gyro (MSG), a disk-type rotor is connected to a synchronous motor through a fluid bearing and the motor is fixed to the frame of the floator. The floator is suspended by magnetic force without any mechanical contact so that high-accuracy measurement is possible. According to this concept, a 6-degree-of-freedom (DOF) active MSG was developed. However, because the MSG used magnetic attraction pulling upward against gravity, it has high power consumption. In addition, the miniaturization of the MSG was difficult because four pairs of electromagnets were arranged on opposite sides of the floator. To solve these problems, a 2-DOF active magnetically suspended micro gyro (MSMG) is designed and fabricated. In this gyro, the 4-DOF motions of the floator are constrained by a cross spring and a gimbal. The two rotational degrees of motion of the floator is controlled by four electromagnets. The gyro with such configuration is suitable for miniaturization and low-cost fabrication. This paper shows basic concepts and measurement principle of the 2-DOF active MSMG.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110009976187, CiNii Books ID：AA11902241
• B02 Zero-power Control of Double Parallel Magnetic Suspension System with Parallel Connected Coils　　　　　　　　　　　　　　　
  NARISAWA Yoshinori; MIZUNO Takeshi; TAKASAKI Masaya; ISHINO Yuji
  Dynamics and Design Conference, Volume：2013, Number：13, First page："B02, Last page：1"-"B02-10", 25 Aug. 2013
  Parallel magnetic suspension has been proposed where multiple floators are controlled with a single power amplifier. The feasibility of voltage-controlled double parallel magnetic suspension with parallel connected coils has been already demonstrated in the previous work. This study focuses on the zero-power control in a voltage-controlled double parallel suspension system with parallel connected coils. In this system, there are three methods of achieving zero-power control: feeding back the control voltage, either or the sum of the coil currents. This paper shows the conditions for the system with each zero-power controller to be controllable, and compares their performances.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110009976178, CiNii Books ID：AA11902241
• B01 Development of Tri-axial Microforce Measurement Apparatus Using Series Magnetic Suspension　　　　　　　　　　　　　　　
  ISHII Kazunari; TAKASAKI Masaya; ISHINO Yuji; MIZUNO Takeshi
  Dynamics and Design Conference, Volume：2013, Number：13, First page："B01, Last page：1"-"B01-10", 25 Aug. 2013
  Series magnetic suspension is applied to force measurement. In a double series magnetic suspension system, two floators are suspended with a single electromagnet. When PID control is applied to the lower (second) floator and force acts on the lower floator, the upper (first) floator displaces whereas the lower floator is maintained at the original position. Therefore, the force can be estimated for the displacement of the upper floator. When the parameters are set appropriately, small force leads to large displacement so that the proposed measurement method is suitable for noncontact measurement of micro force. In this work, an apparatus for tri-axis force measurement was fabricated. Force measurements were carried out with the apparatus. The results show that three-dimensional forces were measured with a high resolution by the developed apparatus.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110009976177, CiNii Books ID：AA11902241
• C19 Active Vibration Isolation System with an Active Dynamic Vibration Absorber : 3rd Report:Realization of Acceleration Feedback　　　　　　　　　　　　　　　
  SEKIYA Hiroaki; MIZUNO Takeshi; TAKASAKI Masaya; ISHINO Yuji
  Dynamics and Design Conference, Volume：2013, Number：13, First page："C19, Last page：1"-"C19-7", 25 Aug. 2013
  This paper describes the effectiveness of an active vibration isolation system that uses an active dynamic absorber as a servo accelerometer in a low-frequency range and a vibration control device in a high-frequency range. Complimentarily, it uses an air actuator as a control device in a low-frequency range and a low-cost accelerometer as a sensing device in a high-frequency range. The main aim of this research is to develop a high performance active vibration isolation system that is lower in cost than conventional active vibration system. It was experimentally demonstrated that the acceleration in a low frequency range can be detected from the control input of the absorber. In addition, by feeding back the estimated acceleration, the vibration was actually attenuated.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110009976233, CiNii Books ID：AA11902241
• 2A1-A04 Measurement of Perceptual Threshold on Surface Acoustic Wave Tactile Display(Tactile and Force Sensing (1))　　　　　　　　　　　　　　　
  TAKADA Hiroki; TAMON Ryo; TAKASAKI Masaya; MIZUNO Takeshi
  Volume：2013, First page："2A1, Last page：A04(1)"-"2A1-A04(3)", 22 May 2013
  When we rub physical surface with pen or stylus, we can feel tactile sensation through it. The reproducing of such realistic tactile sensation is focused recently and some devices have been developed. On the other hand, many devices proposed only low frequency sensation, that frequency is considered as peak frequency of mechanoreceptor sensitivity. In this research, adding high frequency vibration to tactile sensation indication was proposed. To confirm high frequency vibration on surface acoustic wave (SAW) tactile display, its frequency response was measured. We conducted a psychological test to investigate the perceptual threshold that human can feel on SAW tactile display. We confirmed that human feel the high frequency vibration.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110009963185, CiNii Books ID：AA11902933
• (13)多重磁気浮上システム : 第1報,基本構想と基本定理(論文,日本機械学会賞〔2012年度(平成24年度)審査経過報告〕)　　　　　　　　　　　　　　　
  水野 毅; 高崎 正也; 石野 祐二
  Volume：116, Number：1134, First page：293, Last page：293, 05 May 2013
  Japanese
  ISSN：0021-4728, CiNii Articles ID：110009612051, CiNii Books ID：AN00187394
• 21413 Microforce Measurement Using a Zero-compliance Mechanism : 1st report: Fabrication of an Apparatus Using a Voice Coil Motor　　　　　　　　　　　　　　　
  TAKABAYASHI Atsushi; MIZUNO Takeshi; ISHINO Yuji; Takasaki Masaya
  Volume：2013, Number：19, First page：607, Last page：608, 14 Mar. 2013
  Zero-compliance system is applied to micro-force measurement. The system measures the force from the displacement of a detection point without displacing the point of force. The efficiency was proved by an experimental apparatus using series magnetic suspension. It could measure the force at high resolution under the condition that the displacement of the point of force was zero. However, it used magnetic force to achieve negative stiffness so that the accuracy of measurement was limited because of the non-linearity. To solve such a problem, this study develops an experimental apparatus that consists of a parallel spring device and a voice coil motor as an actuator. Measurement tests are earned out with the apparatus.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110009954695, CiNii Books ID：AA11902161
• 21102 Study on AC Magnetic Suspension Using Magnetic Resonant Coupling 1st report: Principles of Suspension　　　　　　　　　　　　　　　
  TAKAHASHI Kei; TAKASAKI Masaya; ISHINO Yuji; MIZUNO Takeshi
  Volume：2013, Number：19, First page：499, Last page：500, 14 Mar. 2013
  A novel AC magnetic suspension using magnetic resonant coupling is proposed and studied both theoretically and experimentally. The conventional AC magnetic suspension with energy transfer function has a problem that energy transfer efficiency is very low because it has a gap. In contrast, even if it has a gap, the energy transfer method using magnetic resonant coupling has high efficiency. In this paper, this method is combined with AC magnetic suspension. An experimental apparatus is fabricated for basic study. The floator was successfully suspended without control, and the self-stabilization characteristic is confirmed.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110009954641, CiNii Books ID：AA11902161
• 21110 Multiple Magnetic Suspension Systems 13 th report : Structure of Zero-power Controller for Parallel Suspension　　　　　　　　　　　　　　　
  NARISAWA Yoshinori; MIZUNO Takeshi; TAKASAKI Masaya; ISINO Yuji
  Volume：2013, Number：19, First page：515, Last page：516, 14 Mar. 2013
  Parallel magnetic suspension has been proposed where multiple floators are controlled with a single power amplifier. The feasibility of double parallel magnetic suspension with zero-power controller has been already demonstrated in the previous work. The zero-power control was achieved by feeding back the integral of the coil current. To achieve stable zero-power suspension, the feedback gain of the integral was positive in usual single magnetic suspension system, and negative in double magnetic suspension system. This paper shows analytically that the sign of the integral gain depends on the multiplicity (number of floators), it is positive for odd multiplicity whereas negative for even multiplicity.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110009954649, CiNii Books ID：AA11902161
• 21107 Measurement Sensitivity Evaluation of a Totally Active Magnetically Suspended Gyro　　　　　　　　　　　　　　　
  AKIYAMA Tomohiro; OBARA Kyosuke; TAKASAKI Masaya; ISHINO Yuji; MIZUNO Takeshi
  Volume：2013, Number：19, First page：509, Last page：510, 14 Mar. 2013
  A six-degree-of-freedom (DOF) active magnetically suspended gyro (MSG) is developed and its performances are estimated. In MSG, a disk-type rotor is connected to a synchronous motor through fluid bearing, the motor is fixed to the frame and the frame is suspended by magneticforce without any mechanical contact; According to this concept, a three-DOF active MSG was developed. However, because of poor damping in the passive suspension and low resolution of displacement sensor, measurement accuracy was relatively low. To solve these problems, a totally (six-DOF) active MSG was fabricated. In this paper, the influence of displacement sensor noise on angular velocity measurement is examined. Since the totally active MSG's displacement sensor is more sensitive than the three-DOF active MSG's, the totally active MSG has less noise of measurement angular velocity than the three-DOF active MSG.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110009954646, CiNii Books ID：AA11902161
• Realization of Zero-power Control in a Voltage-controlled Double Parallel Suspension System with Parallel Connection　　　　　　　　　　　　　　　
  成澤 慶宜; 高崎 正也; 石野 裕二
  Volume：2012, Number：63, First page：75, Last page：78, 13 Dec. 2012
  Japanese
  CiNii Articles ID：40019555945, CiNii Books ID：AA12475827
• Performance Evaluation of a Totally Active Magnetically Suspended Gyro　　　　　　　　　　　　　　　
  秋山 智広; 石野 裕二; 高崎 正也
  Volume：2012, Number：63, First page：71, Last page：74, 13 Dec. 2012
  Japanese
  CiNii Articles ID：40019555926, CiNii Books ID：AA12475827
• 836 Multiple Magnetic Suspension Systems : 12th report: Zero-power Control of Voltage-Controlled Parallel Suspension　　　　　　　　　　　　　　　
  MIZUNO Takeshi; NISHIMURA Kazuya; ISHINO Yuji; TAKASAKI Masaya
  Dynamics & Design Conference, Volume：2012, First page："836, Last page：1"-"836-9", 18 Sep. 2012
  This paper discusses the feasibility of zero-power control in voltage-controlled parallel magnetic suspension systems. Parallel magnetic suspension systems are classified into two types based on the connection of the multiple coils: series connection and parallel connection. To achieve zero-power control, the integral of current is fed back in the former type whereas the integral of voltage is fed back in the latter. It is proved that each parallel magnetic suspension system incorporating the zero-power controller can assign the poles arbitrarily when the original system is controllable. It is also shown analytically that the current converges to zero in the steady state even when stepwise disturbances act on the floators in both designed systems.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110009908206, CiNii Books ID：AA12120184
• 834 Development of Variable Flux-Path Magnetic Suspension System Using Flux Concentration　　　　　　　　　　　　　　　
  TAKABAYSHI Atsushi; MIZUNO Takeshi; TAKASAKI Masaya; ISHINO Yuji
  Dynamics and Design Conference : D & D, Volume：2012, First page：127, Last page：127, 17 Sep. 2012
  The Japan Society of Mechanical Engineers, Japanese
  ISSN：1348-0235, CiNii Articles ID：110009953325, CiNii Books ID：AA11901770
• 1A1-B05 Tactile Display Using Surface Acoustic Wave Excited by Pulse Wave(Tactile and Force Sensing(1))　　　　　　　　　　　　　　　
  TAMON Ryo; TAKADA Hiroki; TAKASAKI Masaya; MIZUNO Takeshi
  Volume：2012, First page："1A1, Last page：B05(1)"-"1A1-B05(4)", 27 May 2012
  Previously active type surface acoustic wave (SAW) tactile display has been proposed. SAW tactile display using glass substrate has been developed. SAW excitation by pulse wave has been also proposed. SAW can be excited by low-frequency pulse wave. Applying the SAW excitation by pulse wave to the SAW tactile display using glass substrate, the size of the display can be expanded. This paper describes tactile display using SAW excited by pulse wave. Vibration of the surface of tactile display and observation result of velocity change in rubbing motion are also reported.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110009907225, CiNii Books ID：AA11902933
• 1701 Multiple Electrostatic Suspension System : 5th report:Voltage control using variable capacitor　　　　　　　　　　　　　　　
  KATO Takaaki; MIZUNO Takeshi; ISHINO Yuji; TAKASAKI Masaya
  Volume：2012, Number：18, First page：5, Last page：6, 08 Mar. 2012
  Voltage control using variable capacitor was applied to multiple electrostatic suspension The multiple suspension indicates the simultaneous control of several electrostatic suspension systems with a single power amplifier In this work the power amplifier is replaced by the voltage control system using a variable capacitor, which is connected in series to the controlled objects and a constant power supply The characteristics of the proposed system were studied analytically Double parallel electrostatic suspension was achieved.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110009955188, CiNii Books ID：AA11902161
• 1704 Driving of Piezoelectric Actuator Using Variable Capacitor　　　　　　　　　　　　　　　
  MIZUNO Takeshi; TAKASAKI Masaya; ISHINO Yuji; KONNO Yuta
  Volume：2012, Number：18, First page：11, Last page：12, 08 Mar. 2012
  A new open-loop driving method of piezoelectric actuator is proposed which is characterized by using variable capacitor. The actuator and the variable capacitor is connected m series and a constant voltage is applied to this connection. The charge of the actuator is controlled by adjusting the value of the variable capacitor. In the experiment, the variable capacitor is realized by switching the connections of several prepared capacitors. The Experimental results demonstrate that hysteresis is rather small in the proposed driving system.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110009955191, CiNii Books ID：AA11902161
• 1702 Optimization of Variable Flux-Path Magnetic Suspension System Using Flux Concentration　　　　　　　　　　　　　　　
  TAKABAYASHI Atsushi; ISHINO Yuji; Takasaki Masaya; MIZUNO Takeshi
  Volume：2012, Number：18, First page：7, Last page：8, 08 Mar. 2012
  Variable flux-path magnetic suspension using flux concentration is studied analytically It was shown that flux-concentration type can produce larger suspension force than the conventional variable flux-path system using ferromagnetic control plate. However, it was difficult to achieve stable suspension, since the control (variable) force was not so large, To solve such a problem, the characteristics of the suspension system are studied by finite element analysis. In particular, the effects of the direction of motion, the operating positions and the shape of the control plates were investigated.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110009955189, CiNii Books ID：AA11902161
• 2009 Mass Measurement Using the Fixed-Point of a Spring-Mass System with a Dynamic Absorber : 4th report: Mass measurement　　　　　　　　　　　　　　　
  YAMAOTO Satoru; ISHINO Yuji; TAKASAKI Masaya; MIZUNO Takeshi
  Volume：2012, Number：18, First page：109, Last page：110, 08 Mar. 2012
  The performance of a mass measurement system with a damped dynamic vibration absorber was studied xperimentally. The measurement system utilizes the fixed point of a mass-spring system with a dynamic vibration absorber so that mass is estimated independently of damping in the absorber. It is characterized by using the phase-looked loop to achieve the tuning condition. The principle of measurement was described based on a mathematical model. A measuring apparatus was designed and fabricated. Several basic characteristics were studied experimentally. The average error of measurement was within 0.2%.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110009955240, CiNii Books ID：AA11902161
• G100072 Noncontact Microforce Measurement Using Series Magnetic Suspension : 1st report: Measurement Principle　　　　　　　　　　　　　　　
  SEKINE Daisuke; MIZUNO Takeshi; TAKASAKI Masaya; ISHINO Yuji
  Mechanical Engineering Congress, Japan, Volume：2011, First page："G100072, Last page：1"-"G100072-5", 11 Sep. 2011
  Series magnetic suspension is applied to force measurement. In a double series magnetic suspension system with PID control, the upper floator displaces when force acts on the lower floator. Therefore, the force can be estimated for the displacement of the upper floator. When the parameters are set appropriately, small force leads to large displacement so that the proposed measurement method can be suitable for noncontact measurement of microforce. An apparatus was fabricated to study the effectiveness of the proposed method experimentally.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110009758958, CiNii Books ID：AA12588255
• 141 Noncontact Microforce Measurement Using Series Magnetic Suspension : 2nd report : Fabrication of an Experimental Apparatus　　　　　　　　　　　　　　　
  MIZUNO Takeshi; SEKINE Daisuke; TAKASAKI Masaya; ISHINO Yuji
  Dynamics and Design Conference : D & D, Volume：2011, First page：27, Last page：27, 04 Sep. 2011
  The Japan Society of Mechanical Engineers, Japanese
  ISSN：1348-0235, CiNii Articles ID：110009689826, CiNii Books ID：AA11901770
• C203 Mass Measurement Using the Fixed-Point of a Spring-Mass System with a Dynamic Vibration Absorber : 2nd report: Fabrication of a Measuring Apparatus　　　　　　　　　　　　　　　
  MIZUNO Takeshi; TAKASAKI Masaya; YAMAMOTO Satoru; ISHINO Yuji
  Dynamics and Design Conference, Volume：2011, Number：12, First page：357, Last page：360, 28 Jun. 2011
  A new method of measuring mass under weightless has been proposed. It utilizes the fixed point of a mass-spring system with a dynamic vibration absorber so that mass is estimated independently of the damping in the absorber. It is characterized by using the phase-looked loop to achieve the tuning condition. The principal of measurement is described based on a mathematical model. A measuring apparatus is designed and fabricated. Several basic characteristics are studied experimentally.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110009619600, CiNii Books ID：AA11902241
• A101 Multiple Electrostatic Suspension Systems : 4th report: Experimental study on dynamic characteristics of a double suspension system　　　　　　　　　　　　　　　
  KATO Takaaki; MIZUNO Takashi; TAKASAKI Masaya; ISHINO Yuji
  Dynamics and Design Conference, Volume：2011, Number：12, First page：19, Last page：22, 28 Jun. 2011
  Multiple electrostatic suspension suspends multiple floator with a single power amplifier. The controllability of the parallel-connected double suspension system was previously analyzed, and the conditions to be controllable were shown. To test the analytical results, 1-DOF suspension systems were fabricated, and they composed a parallel-connected double electrostatic suspension system. The feasibility of double electrostatic suspension was demonstrated experimentally. This paper showed a basic model of proposed system, the controllability, and the realization of double electrostatic suspension with the fabricated suspension system. Dynamic characteristics of double electrostatic suspension was researched based on frequency responses.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110009619533, CiNii Books ID：AA11902241
• A103 Wind-Tunnel for Spinning Body Using Magnetic Suspension : 5th report: Wind-tunnel Tests　　　　　　　　　　　　　　　
  MIZUNO Takeshi; SAKAI Yasuhiro; TAKASAKI Masaya; ISHINO Yuji
  Dynamics and Design Conference, Volume：2011, Number：12, First page：29, Last page：32, 28 Jun. 2011
  A wind-tunnel system for spinning body has been proposed to measure hydrodynamic forces acting on the body. In the proposed system, the body is suspended and rotated by electromagnets. The forces are measured from the control signal for suspension. An experimental apparatus was developed which has eight electromagnets around a wind-tunnel and an differential-type optical displacement sensor for detecting the three-dimensional positions of the body. Stable suspension, three-dimensional positioning and rotation of the body were achieved. This paper reports the measurement of the hydrodynamic force acting on the spinning body.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110009619535, CiNii Books ID：AA11902241
• 208302 Variable Flux-Path Magnetic Suspension System Using Flux Concentration　　　　　　　　　　　　　　　
  YONENO Yuuki; MIZUNO Takeshi; TAKASAKI Masaya; ISHINO Yuji
  Volume：2011, Number：17, First page：263, Last page：264, 17 Mar. 2011
  Variable flux-path magnetic suspension system has been proposed as one of the magnetic suspension systems, which controls the attractive force by moving a pair of control plates located between the permanent magnet and the floator. In this paper, a new variable flux-path magnetic suspension system using flux concentration is proposed. This system has permanent magnet plates as control plates while conventional system has ferromagnetic plates, so that the increase of attractive force can be expected. To verify the prediction, distribution of flux density and attractive force were analyzed by using FEM. These analyses clarified the increase of attractive force and relations between the attractive force and the distance of the control plates. To test the analytical results, an experimental apparatus was fabricated. The measurement results support the analytical predictions.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110009663850, CiNii Books ID：AA11902161
• 207104 Wind-Tunnel for Spinning Body Using Magnetic Suspension : 3rd report : Development of 60×6Omm wind-tunnel system and realization of levitation　　　　　　　　　　　　　　　
  SAKAI Yasuhiro; MIZUNO Takeshi; TAKASAKI Masaya; ISHINO Yuji
  Volume：2011, Number：17, First page：213, Last page：214, 17 Mar. 2011
  A wind-tunnel system for spinning body has been proposed to measure hydrodynamic forces acting on the body. In the proposed system, the body is suspended and rotated by electromagnets. The forces are measured from the control signal for suspension. In the conventional apparatus, eight electromagnets were placed around the wind-tunnel. An optical displacement sensor was used to detect the three-dimensional positions of the body. Stable suspension and three-dimensional positioning of the body were achieved. However, the conventional apparatus has some problems. In this paper, a new wind-tunnel using magnetic suspension to improve such problems is fabricated. Stable suspension using fabricated apparatus is achieved.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110009663825, CiNii Books ID：AA11902161
• 207102 Multiple Electrostatic Suspension Systems : 3rd report : Realization of double electrostatic suspension　　　　　　　　　　　　　　　
  KATO Takaaki; MIZUNO Takeshi; TAKASAKI Masaya; ISHINO Yuji
  Volume：2011, Number：17, First page：209, Last page：210, 17 Mar. 2011
  The feasibility of multiple electrostatic suspension is demonstrated experimentally. The concept of the proposed suspension system is to suspend multiple floators with a single power amplifier. According to the structure of systems, they can be divided into series-connected systems or parallel-connected systems. The controllability of each system was previously analyzed, and the conditions to be controllable were shown. To test the analytical results, 1-DOF suspension systems were fabricated, and they composed a parallel-connected double electrostatic suspension system. This paper showed a basic model of proposed system, the controllability, and the realization of double electrostatic suspension with the fabricated suspension system.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110009663823, CiNii Books ID：AA11902161
• 207105 Development of Mass Measurement System Using Velocity Relay Feedback : 1st report : Mass Estimation Considering Stiffness　　　　　　　　　　　　　　　
  AIZAWA Hiromichi; MIZUNO Takeshi; TAKASAKI Masaya; ISHINO Yuji
  Volume：2011, Number：17, First page：215, Last page：216, 17 Mar. 2011
  This paper treats a relay-feedback mass measurement system that uses a relay with hysteresis and feedback the velocity of the object. A new apparatus is fabricated for precise measurement, in which a pair of plate springs are used for suspending the object without friction. The effect of these springs on mass estimation is investigated analytically. An estimating equation including this effect is derived. Experiments carried out with the apparatus demonstrates that the derived estimating equation is valid.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110009663826, CiNii Books ID：AA11902161
• 208301 Multiple Magnetic Suspension Systems : 11^ : Realization of Zero-power Control of a Double Parallel Magnetic Suspension with Different Magnetic Polarities　　　　　　　　　　　　　　　
  SAKURADA Takumi; MIZUNO Takeshi; TAKASAKI Masaya; ISHINO Yuji
  Volume：2011, Number：17, First page：261, Last page：262, 17 Mar. 2011
  Multiple magnetic suspension suspends multiple floators with a single power amplifier. It is classified into parallel magnetic suspension and series magnetic suspension. Parallel magnetic suspension systems are classified according to the output type of amplifier and the connection method of coils. This paper focuses on the current-controlled series-connected multiple suspension system. The feasibility of the zero-power control in the parallel magnetic suspension system with different polarities is demonstrated experimentally. The zero-power control is achieved by using PD control and introducing a minor feedback of the integral of the current. It was confirmed experimentally that the coil current converged to zero for constant disturbances in the designed control system.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110009663849, CiNii Books ID：AA11902161
• Fabrication of a Variable Magnetic Flux Unit Using a Single Voice Coil Motor　　　　　　　　　　　　　　　
  MIZUNO Takeshi; NAGANO Yuta; ISHINO Yuji; TAKASAKI Masaya
  Volume：2010, Number：73, First page：67, Last page：71, 16 Dec. 2010
  Japanese
  CiNii Articles ID：10031118808, CiNii Books ID：AN10074612
• 730 Study of Carrier with Magnetic Suspension using Negative Stiffness　　　　　　　　　　　　　　　
  ISHINO Yuji; Mizuno Takeshi; Takasaki Masaya
  Dynamics & Design Conference, Volume：2010, First page："730, Last page：1"-"730-6", 14 Sep. 2010
  This paper presents an application of negative stiffness to carrier suspension system. The suspension is located under the center of gravity of the carrier system, which is similar to that in automobiles. In the conventional positive stiffness suspension system, the loading platform tilts to the unstable direction by inertial force during acceleration and turning. deceleration and This problem can be solved by using a suspension with negative stiffness because, the platform tilts to the stable direction, which is similar to the pendulum-type carrier. The negative stiffness is realized by zero-power magnetic suspension with disturbance feed-forward control.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110008740683, CiNii Books ID：AA12120184
• 736 Multiple Magnetic Suspension Systems : 8^ report: Realization of Double Parallel Magnetic Suspension with Different Magnetic Polarity　　　　　　　　　　　　　　　
  SAKURADA Takumi; MIZUNO Takeshi; TAKASAKI Masaya; ISHINO Yuji
  Dynamics & Design Conference, Volume：2010, First page："736, Last page：1"-"736-5", 14 Sep. 2010
  Multiple magnetic suspension suspends multiple floators with a single power amplifier. It is classified into parallel magnetic suspension and series magnetic suspension. In this paper, the feasibility of parallel magnetic suspension is studied experimentally. Parallel magnetic suspension systems are classified into according to the output type of amplifier and the connection method of coils. However, the polarity of electromagnet has not been treated yet. This paper focuses on the current-controlled multiple suspension system with different polarities. Stable levitation with two floaters is achieved by using PD control.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110008740689, CiNii Books ID：AA12120184
• 2A16 Development of a Flux-Path Control Magnetic Suspension System with Swing-Type Control Plates　　　　　　　　　　　　　　　
  SAKAI Yasuhiro; ISHINO Yuji; TAKASAKI Masaya; MIZUNO Takeshi
  Dynamics and Design Conference, Volume：2010, First page："2A16, Last page：1"-"2A16-9", 17 Aug. 2010
  A new variable flux-path unit is developed for flux-path control magnetic suspension with multiple magnetic sources. The authors have proposed the variable flux-path magnetic suspension system as a unique magnetic suspension system using permanent magnet. This system has ferromagnetic plates between a permanent magnet and a floator. The flux from the permanent magnet to the floator, and the attractive force acting on the floator can be adjusted by the motion control of the control plates. Stable suspension and 2-DOF control with a single magnetic source was achieved. However, the horizontal control force was much less than the vertical control force. In this paper, flux-path control magnetic suspension with multiple magnetic sources is proposed. An experimental apparatus with a variable flux-path unit is developed for realizing multiple-magnetic-source systems. Basic characteristics of the apparatus are measured. Stable levitation is achieved by applying PD and PID controls. In addition, stable levitation with zero-power control is also achieved.
  The Japan Society of Mechanical Engineers, English
  CiNii Articles ID：110009976712, CiNii Books ID：AA11902241
• 2A11 Series-Type Multiple Magnetic Suspension System　　　　　　　　　　　　　　　
  MIZUNO Takeshi; MARUYAMA Yutaka; TAKASAKI Masaya; ISHINO Yuji; OSHIBA Yusuke
  Dynamics and Design Conference, Volume：2010, First page："2A11, Last page：1"-"2A11-12", 17 Aug. 2010
  In this paper, series-type multiple magnetic suspension systems are studied. Several floators are suspended in series by one electromagnet in these systems. The nearest floator by the electromagnet is directly suspended by the electromagnet. The others are indirectly suspended by the attractive force due to the magnetization of the floators. The controllability and observability of series-type multiple magnetic suspension systems that have arbitrary number of floators, and in which the nearest floator by the electromagnet is detected are proved mathematically. A series-type multiple magnetic suspension system was fabricated in order to verify the analyses experimentally. In the fabricated system, magnetic suspension units that are equipped with a sensor and an electromagnet are used instead of the normal floators to study on various conditions. As the first step to realize the levitation of multi floators using one electromagnet and one sensor, a basic trial is carried out in the fabricated system.
  The Japan Society of Mechanical Engineers, English
  CiNii Articles ID：110009976707, CiNii Books ID：AA11902241
• 2A22 Application of Switching Stiffness Control to Magnetic Suspension System for Increasing Load Capacity　　　　　　　　　　　　　　　
  ISHINO Yuji; MIZUNO Takeshi; TAKASAKI Masaya
  Dynamics and Design Conference, Volume：2010, First page："2A22, Last page：1"-"2A22-13", 17 Aug. 2010
  This paper presents a method of increasing the load capacity of magnetic suspension systems. The limits of coil current and suspension gap determine the load capacity. In PID-controlled systems, the displacement is kept zero and the coil current increases when load is added to the floator. In contrast, the current is kept zero and the gap decreases in zero-power controlled systems. As a result, the load capacity is determined by the current limit in the former and the gap limit in the latter. It can be increased by switching them each other. The switching stiffness control is applied for this purpose. Experimental results demonstrate the operating range is extended almost twice.
  The Japan Society of Mechanical Engineers, English
  CiNii Articles ID：110009976714, CiNii Books ID：AA11902241
• 11813 Multiple Magnetic Suspension System : 5^ report : Current-controlled Parallel-connected Parallel Suspension　　　　　　　　　　　　　　　
  SAKURADA Takumi; MIZUNO Takeshi; TAKASAKI Masaya; ISHINO Yuji
  Volume：2010, Number：16, First page：49, Last page：50, 09 Mar. 2010
  Multiple magnetic suspension suspends multiple floators with a single power amplifier. It is classified into parallel magnetic suspension and series magnetic suspension. In this paper, the feasibility of parallel magnetic suspension is studied experimentally. Parallel magnetic suspension systems are classified into series-connected and parallel connected according to coil connection. This paper focuses on the current-controlled multiple suspension system with parallel connected coils. Stable levitation with two floaters is achieved by using PD control.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110008743515, CiNii Books ID：AA11902161
• Observability of Parallel Magnetic Suspension Systems　　　　　　　　　　　　　　　
  MIZUNO Takeshi; TAKASAKI Masaya; ISHINO Yuji
  Volume：2009, Number：56, First page：39, Last page：42, 17 Dec. 2009
  Japanese
  CiNii Articles ID：10026073650, CiNii Books ID：AN10074612
• B21 Angular Velocity Measurement in Magnetically Suspended Gyro　　　　　　　　　　　　　　　
  MARUYAMA Yutaka; MIZUNO Takeshi; TAKASAKI Masaya; ISHINO Yuji
  Dynamics and Design Conference, Volume：2009, Number：11, First page：287, Last page：290, 01 Sep. 2009
  This paper presents a new-structure rotating gyros using magnetic suspension. A rotating gyro based on an active magnetic bearing (AMB-based gyro) was proposed. However, the miniaturization of the AMB-based gyro is technically difficult because of the limitations on its design and structures. A new structure has been proposed to solve the problem. A prototype of the new gyro has been designed and fabricated. In this paper, the performance of the magnetic suspension of the prototype is evaluated from a viewpoint of frequency response. In addition, angular velocity measurement using the prototype is curried out. The accuracy of measurement is reported.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110008010571, CiNii Books ID：AA11902241
• B24 Stiffness Control by a Local Current Feedback in Magnetic Suspension Systems　　　　　　　　　　　　　　　
  ISHINO Yuji; MIZUNO Takeshi; TAKASAKI Masaya
  Dynamics and Design Conference, Volume：2009, Number：11, First page：299, Last page：302, 01 Sep. 2009
  A control method of adjusting the stiffness of suspension was proposed for magnetic suspension systems whose bias flux is provided by permanent magnets. In such magnetic suspension systems, zero-power control has often been applied. Since the zero-power magnetic suspension system behaves as if it has negative stiffness. So that it is applied to vibration isolation system. However, the amplitude of negative stiffness cannot be adjusted. In this paper, a proportional feedback is incorporated into the minor current feedback loop of the zero-power controller. It is shown that the stiffness can be adjusted by the gain of the added current feedback. This system improves static load performance for magnetic suspension system. The principle and experiment results are presented. When a gap changes in this system, the stiffness also changes. Therefore a nonlinear compensation is included in this system to improve the linearity.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110008010574, CiNii Books ID：AA11902241
• B26 Multiple Magnetic Suspension Systems : 3rd report : Proof of Basic Theorems　　　　　　　　　　　　　　　
  MIZUNO Takeshi; TAKASAKI Masaya; ISHINO Yuji; MARUYAMA Yutaka
  Dynamics and Design Conference, Volume：2009, Number：11, First page：448, Last page：451, 01 Sep. 2009
  The controllability of parallel multiple magnetic suspension systems is discussed based on their basic analytical models. The multiple magnetic suspension systems are classified according to power amplifier and coil connection. This paper focuses on the voltage-controlled multiple suspension system with parallel connected coils. The conditions are clarified under which the system becomes controllable.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110008010604, CiNii Books ID：AA11902241
• 437 Development of a Flux-Path Control Magnetic Suspension System with Swing-Type Control Plates : 2nd Report, Realization of Zero-Power Control　　　　　　　　　　　　　　　
  SAKAI Yasuhiro; ISHINO Yuji; TAKASAKI Masaya; MIZUNO Takeshi
  Dynamics & Design Conference, Volume：2009, First page："437, Last page：1"-"437-4", 03 Aug. 2009
  The variable flux path suspension system is a magnetic suspension system using the force of attraction between a permanent magnet and a ferromagnetic suspension object. Stable suspension and three-dimensional positioning was realized when a single magnetic source was used. However, the horizontal control force was much less than the vertical control force. This paper proposes a variable flux-path suspension system with multiple magnetic sources to make the horizontal force in the same range of the vertical force. A variable flux path module applicable to such multiple magnetic source system is developed. Stable suspension is achieved with this module. In addition, zero-power control is achieved by the feeding back the integral of current of the actuator.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110008087502, CiNii Books ID：AA12120184
• 442 Development of Multiple Magnetic Suspension Systems : 2nd report: Controllability and Observability of Tandem-Type Multiple System　　　　　　　　　　　　　　　
  MARUYAMA Yutaka; OSHIBA Yusuke; ISHINO Yuji; TAKASAKI Masaya; MIZUNO Takeshi
  Dynamics & Design Conference, Volume：2009, First page："442, Last page：1"-"442-5", 03 Aug. 2009
  Tandem-type multiple magnetic suspension system is studied in this paper. In this system, several floators are suspended in series by an electromagnet. The controllability and observability of the system that has arbitrary number of floators are proved. A tandem-type multiple magnetic suspension system was fabricated in order to exam the controllability and observability experimentally. In the fabricated system, magnetic suspension units that include a sensor and an electromagnet are used instead of floators. To realize the complete tandem-type multiple magnetic suspension, basic trial is carried out using the fabricated system.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110008087507, CiNii Books ID：AA12120184
• 20205 Microassembly Using Surface Tension : 4^ report: Effects of Surface Tension on the Formation of Drops　　　　　　　　　　　　　　　
  Haga Tetsuya; Takasaki Masaya; Ishino Yuji; Mizuno Takeshi
  Volume：2009, Number：15, First page：151, Last page：152, 05 Mar. 2009
  A method of picking up a small component by using liquid surface tension is studied. In the previous works ultra-pure water was used as working fluid. This reports investigates on isopropanol (IPA) and its water mixtures. It is found that the maximum wetting angles increase as the ratio of IPA to water decreases and the adsorptive force decrease as the outer diameter of nozzle decrease.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110007722160, CiNii Books ID：AA11902161
• 20206 Development of a Multi-degree-of-Freedom Vibration Isolation System Using Zero-Power Magnetic Suspension Units　　　　　　　　　　　　　　　
  NODA Sho; ISHINO Yuji; TAKASAKI Masaya; MIZUNO Takeshi
  Volume：2009, Number：15, First page：153, Last page：154, 05 Mar. 2009
  The vibration isolation system (VIS) using zero-power magnetic suspension has been investigated toward practical use. In the previous research, a 1-DOF VIS unit used zero-power magnetic suspension for achieving negative stiffness. However, its stiffness could not be adjusted. In this research, a stiffness control technique is applied to the unit for adjusting negative stiffness. In addition, a 3-DOF VIS is constructed by combining three units. The basic characteristics are studied experimentally.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110007722161, CiNii Books ID：AA11902161
• 20210 Electrostatic Actuator Control System Using a Variable Capacitor Mechanism : 5th report: Position Detection Using a Variable Capacitor　　　　　　　　　　　　　　　
  KATO Takaaki; ISHINO Yuji; TAKASAKI Masaya; MIZUNO Takeshi
  Volume：2009, Number：15, First page：161, Last page：162, 05 Mar. 2009
  The voltage applied to the actuator is controlled by varying the capacitance. Non-contact suspension has been achieved by using this control system. In this paper, a method of position detection is proposed. The voltage across the actuator is determined by the capacitance of the actuator and the capacitance of the variable capacitor. Therefore, position of the floator can be estimated by them. This paper shows the principle and basic experiments.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110007722165, CiNii Books ID：AA11902161
• AC Magnetic Suspension System Using a Transformer with a Variable Coupling Factor　　　　　　　　　　　　　　　
  MIZUNO Takeshi; NODA Shou; ISHINO Yuji; TAKASAKI Masaya
  Volume：2008, Number：173, First page：63, Last page：66, 04 Dec. 2008
  Japanese
  CiNii Articles ID：10025672368, CiNii Books ID：AN00346647
• 658 Increasing the Load Capacity of Magnetic Suspension by a Stiffness Switching Control　　　　　　　　　　　　　　　
  ISHINO Yuji; Mizuno Takeshi; Takasaki Masaya
  Dynamics & Design Conference, Volume：2008, First page："658, Last page：1"-"658-6", 02 Sep. 2008
  This paper presents a method of increasing the load capacity of magnetic suspension system with a PID or zero-power controller. In the magnetic suspension systems, load capacity is determined by coil current and suspension gap. In the PID controlled system, the displacement is kept zero and the coil current increases when load is added to the floater. In the zero-power controlled system, the current is kept zero and the gap decrees. The load capacity is therefore determined by the current limit in the former and the gap limit in the latter. This paper shows that the load capacity can be increased by combining both the controls.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110007121393, CiNii Books ID：AA12120184
• 弾性表面波リニアモータの低速高精度速度制御に関する研究　　　　　　　　　　　　　　　
  高崎正也
  2008
• 弾性表面波リニアモータの低速高精度速度制御に関する研究　　　　　　　　　　　　　　　
  高崎正也
  Volume：6 (平成19年度), 2008
• 弾性表面波リニアモータの低速高精度速度制御に関する研究　　　　　　　　　　　　　　　
  高崎正也
  総合研究機構研究プロジェクト成果発表会 : ポスター展示, 2008
• 弾性表面波リニアモータの低速高精度速度制御に関する研究　　　　　　　　　　　　　　　
  高崎正也
  総合研究機構研究プロジェクト研究成果報告書, Volume：6 (平成19年度), 2008
• Principles and Experimental Study of Electrostatic Suspension Using a Variable Capacitor　　　　　　　　　　　　　　　
  MIZUNO Takeshi; TSUKADA Sinya; ISHINO Yuji; TAKASAKI Masaya
  Volume：2007, Number：123, First page：59, Last page：63, 06 Dec. 2007
  Japanese
  CiNii Articles ID：10025671191, CiNii Books ID：AN00346647
• 415 Proposal of Diagnosis using Ultrasonic Dental Scaler with Resonance Frequency Tracing System　　　　　　　　　　　　　　　
  MARUYAMA Yutaka; TAKASAKI Masaya; Kutami Tomonori; ISHINO Yuji; MIZUNO Takeshi
  Dynamics & Design Conference, Volume：2007, First page："415, Last page：1"-"415-4", 25 Sep. 2007
  Ultrasonic dental scalar is the instrument to remove dental calculus using ultrasonic vibration of a transducer. The transducer is used in resonant condition. However, it's resonance frequency change with value of input voltage to the transducer and condition of contact with a tooth or gum, so we produced the system that traces change of resonance frequency and generates driving signal at the frequency. In addition, we proposed to diagnose dental abnormality using the system and transducer. This paper reveals its possibility.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110006651860, CiNii Books ID：AA12120184
• 425 Flux Path Control Magnetic Suspension : 6th report : Attractive force measurement and three-dimensional positioning　　　　　　　　　　　　　　　
  FURUTACHI Munehiro; INABA Shunsuke; TAKASAKI Masaya; ISHINO Yuji; MIZUNO Takeshi
  Dynamics & Design Conference, Volume：2007, First page："425, Last page：1"-"425-5", 25 Sep. 2007
  In the flux-path control magnetic suspension system, the force acting on the floator is controlled by moving a control plates made of ferromagnetic material, which is located between the permanent magnet and the floator. In this paper, the three-dimensional attractive forces acting on the floator were measured with a manufactured load cell. In addition, stable three-dimensional positioning was achieved by applying PD control. Several dynamic characteristics were measured in each direction
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110006652005, CiNii Books ID：AA12120184
• 424 Microassembly using Surface Tension : 1st report:Principle and Basic Experiments　　　　　　　　　　　　　　　
  TAKAGI Hiroshi; TAKASAKI Masaya; ISHINO Yuji; MIZUNO Takeshi
  Dynamics & Design Conference, Volume：2007, First page："424, Last page：1"-"424-4", 25 Sep. 2007
  This paper proposes a new method of handling microchips. In this method, a chip is picked up with a water drop at the head of a nozzle. According to the self-centering effect, the chip comes to the bottom of the water drop automatically. This method has an advantage of catching up and positioning the chip even if there is a deflection between the nozzle and the chip. Fundamental performances of this method are studied experimentally.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110006651945, CiNii Books ID：AA12120184
• 1113 Velocity control of surface acoustic wave linear motor using two-degree-of-freedom control　　　　　　　　　　　　　　　
  KOTANI Hiroyuki; TAKASAKI Masaya; ISHINO Yuji; MIZUNO Takeshi
  Dynamics and Design Conference, Volume：2007, Number：10, First page：12, Last page：15, 08 Aug. 2007
  Surface acoustic wave (SAW) linear motor is a kind of ultrasonic motors. The advantages of the SAW linear motor are thin structure, high thrust force, high velocity and precise positioning. Relationship between applied voltage and output velocity, however, has non-linearity in a low-velocity area due to friction drive principle. Therefore the SAW linear motor cannot obtain stable driving without feedback control in the low-velocity area. Previously, to realize such low velocity, PWM control and flexible slider structure were employed. Flexible structure was installed to cancel vibration due to PWM carrier frequency. In this research, we change calculation algorithm for slider velocity measurement. As a result, SAW linear motor can be driven at a low velocity of 30mm/s. Additionally, driving characteristics is improved by using a feedforward controller.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110007083259, CiNii Books ID：AA11902241
• 2211 Measurement Bandwidth of a Gyroscopic Sensor using Active Magnetic Bearing　　　　　　　　　　　　　　　
  MARUYAMA Yutaka; MIZUNO Takeshi; ISHINO Yuji; TAKASAKI Masaya; ISHIGAMI Takayuki; KAMENO Hironori
  Dynamics and Design Conference, Volume：2007, Number：10, First page：220, Last page：223, 08 Aug. 2007
  A gyroscopic sensor using active magnetic bearing (AMB) is studied in this paper. This sensor has been proposed to realize a compact, high-accuracy, multi-axis, and low-cost sensor. It utilizes the control function of AMB and works as a two-axis gyroscopic sensor and also as a three-axis servo-type accelerometer. Angular velocity measurement is focused in this paper. Angular velocities are estimated from the control signals for canceling gyroscopic and inertial torque acting on the shaft of AMB. In measuring two-axis angular velocity simultaneously, there is the upper limit to the measurement range since the estimation equation has zero as a frequency. Several numerical simulations and experiments with a conventional-size AMB are used to investigate the properties of the zero extensively.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110007083224, CiNii Books ID：AA11902241
• 21615 Improvement of driving characteristics for ultra-low speed surface acoustic wave linear motor　　　　　　　　　　　　　　　
  KOTANI Hiroyuki; TAKASAKI Masaya; ISHINO Yuji; MIZUNO Takeshi
  Volume：2007, Number：13, First page：7, Last page：8, 15 Mar. 2007
  Surface acoustic wave (SAW) linear motor is a kind of ultrasonic motors. The advantages of the SAW linear motor is thin structure, high thrust force, high velocity and precise positioning. Relationship between applied voltage and output velocity, however, has non-linearity in a low-velocity area due to friction drive principle. Therefore the SAW linear motor cannot obtain stable driving without feedback control in the low-velocity area. Previously, to realize such low velocity, PWM control and flexible slider structure were employed. Flexible structure was installed to cancel vibration due to PWM carrier frequency. In this research, we change calculation algorithm for slider velocity measurement. As a result, SAW linear motor can be driven at a low velocity of 35μm/s. Additionally, driving characteristics is improved by using a feedforward controller.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110007083269, CiNii Books ID：AA11902161
• 21614 Control of Negative Stiffness by a Local Current Feedback in Magnetic Suspension Systems : (2nd Report) Switching Control of Stiffness with a Saturation Element　　　　　　　　　　　　　　　
  ISHINO Yuji; TAKASAKI Masaya; MIZUNO Takeshi
  Volume：2007, Number：13, First page：5, Last page：6, 15 Mar. 2007
  A control method of realizing negative stiffness that uses local current feedback is modified to widen its operation range. The modified controller changes stiffness from negative to positive for large disturbance. The switching function is realized with a saturation element added to the integrator. The efficacy of the modified controller is shown experimentally.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110007083268, CiNii Books ID：AA11902161
• 21612 Electrostatic Actuator Control System Using a Variable Capacitor Mechanism : 3rd report: Experiment for electrostatic levitation　　　　　　　　　　　　　　　
  TSUKADA Shinya; TAKASAKI Masaya; ISHINO Yuji; MIZUNO Takeshi
  Volume：2007, Number：13, First page：1, Last page：2, 15 Mar. 2007
  Electrostatic levitation is achieved with the control system that is characterized by using a variable capacitor mechanism. In the control system, a variable capacitor is connected with an electrostatic actuator in series. A constant high voltage is applied to this connection. The voltage applied to the actuator is controlled by changing the capacitance of the variable capacitor. An apparatus was fabricated for electrostatic levitation. The capability of electrostatic levitation by the proposed control system was verified experimentally.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110007083266, CiNii Books ID：AA11902161
• 21623 Study on Magnetic Suspension Using a Variable Flux-Path Mechanism : 5th Report, Suspension of a Kg-order Object　　　　　　　　　　　　　　　
  INABA Shunsuke; FURUTACHI Munehiro; MIZUNO Takeshi; ISHINO Yuji; TAKASAKI Masaya
  Volume：2007, Number：13, First page：23, Last page：24, 15 Mar. 2007
  A new magnetic suspension using a variable flux-path has been proposed. The flux of the permanent magnet to floator is controlled by moving ferromagnetic plates between them. The lateral position of ferromagnetic plates is changed by an actuator. In the previous works, a 100-g steel ball was supported and controlled in three dimensions using this mechanism. The purpose of this study is to suspend a kg-order object and controlled it in three dimensions. This study shows that a one-kg steel ball can be supported by magnetic suspension using a variable flux-path mechanism.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110007083430, CiNii Books ID：AA11902161
• 4216 Control of Negative Stiffness by a Local Current Feedback in Magnetic Suspension Systems : (3rd Report) Study on dynamic characteristics　　　　　　　　　　　　　　　
  ISHINO Yuji; TAKASAKI Masaya; MIZUNO Takeshi
  Volume：2007, Number：3, First page：301, Last page：302, 2007
  Japanese
  CiNii Articles ID：110007113400, CiNii Books ID：AA12113972
• 4219 Vibration Isolation System Using Zero-Power Control : Fabrication of a Vibration Isolation Unit with a Weight Support Mechanism　　　　　　　　　　　　　　　
  INABA Shunsuke; MIZUNO Takeshi; ISHINO Yuji; TAKASAKI Masaya
  Volume：2007, Number：3, First page：307, Last page：308, 2007
  Japanese
  CiNii Articles ID：110007113429, CiNii Books ID：AA12113972
• 4224 Experimental study of Fundamental Characteristic of Ultrasonic Cutter　　　　　　　　　　　　　　　
  YAMAMOTO Kazuya; HARA Toshiaki; TAKASAKI Masaya; ISHINO Yuji; MIZUNO Takeshi
  Volume：2007, Number：3, First page：317, Last page：318, 2007
  Japanese
  CiNii Articles ID：110007113402, CiNii Books ID：AA12113972
• 4217 Mass Measurement Using the Oscillation of a Relay Control System with Velocity Feedback : Experimental Study of the Effects of Disturbance on Mass Measurement　　　　　　　　　　　　　　　
  ADACHI Takahiro; MIZUNO Takeshi; ISHINO Yuji; TAKASAKI Masaya
  Volume：2007, Number：3, First page：303, Last page：304, 2007
  Japanese
  CiNii Articles ID：110007113416, CiNii Books ID：AA12113972
• Realization of Electrostatic Levitation by Voltage Control Using a Variable Capacitor　　　　　　　　　　　　　　　
  MIZUNO T.; TSUKADA Shinya; TAKASAKI Masaya; ISHINO Yuji
  Proc. 10th Symaposium on Motion and Vibration Control, 2007, First page：236, Last page：239, 2007
  A novel control method of electrostatic actuators is applied to electrostatic suspension. This method uses a variable capacitor, which is connected with an electrostatic actuator in series. A constant high voltage is applied to this connection. The voltage applied to the actuator is controlled by varying the capacitance of the connected capacitor. An experimental apparatus was fabricated for studying the controllability of the electrostatic force by the proposed method. The experimental results showed that electrostatic force can be controlled both statically and dynamically. Another apparatus was fabricated for checking the feasibility of electrostatic suspension. Noncontact electrostatic suspension was achieved with the developed control system.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110007083221, CiNii Books ID：AA11902241
• 21620 Micro Gyroscopic Sensor using Active Magnetic Bearing : 3rd Report: Estimation of Tow-axis Angular Velocity Measurement in Frequency Domain　　　　　　　　　　　　　　　
  MARUYAMA Yutaka; MIZUNO Takeshi; ISHINO Yuji; TAKASAKI Masaya; ISHIGAMI Takayuki; KAMENO Hironori
  First page：17, Last page：18, 2007
  This paper estimates the principle of two-axis angular velocity measurement in gyroscopic sensor using active magnetic bearing. In the sensor, angular velocities are measured based on the control signals to cancel gyroscopic toques operated to the shaft in the AMB. In measuring two-axis angular velocity at the same time, the control signals to cancel inertial toques must be considered in addition to the gyroscopic toques for precise measurement. However, effect of the considering the control signal to cancel the inertial toque never been revealed. The effect is studied in this paper.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110007083433, CiNii Books ID：AA11902161
• Magnetic Suspension Using a Transformer with a Variable Coupling Factor　　　　　　　　　　　　　　　
  MIZUNO Takeshi; ITANI Yusuke; ISHINO Yuji; TAKASAKI Masaya
  Volume：2006, Number：167, First page：51, Last page：54, 07 Dec. 2006
  Japanese
  CiNii Articles ID：10018460410, CiNii Books ID：AN00346647
• 21011 Modular Vibration Isolation System Using Zero-Power Magnetic Suspension : Vibration Isolation Unit with a weight support mechanism　　　　　　　　　　　　　　　
  Kawachi Y.; Ishino Y.; Takasaki M.; Mizuno T.
  Volume：2006, Number：12, First page：73, Last page：74, 09 Mar. 2006
  A vibration isolation unit with a weight support mechanism is developed for an active vibration isolation system using a parallel mechanism. The basic characteristics of the unit are measured for designing the zero-power controller. The zero-power control was achieved in the developed unit. It is experimentally shown that the unit has high stiffness against s static direct disturbance.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110006638515, CiNii Books ID：AA11902161
• 21008 Low velocity driving for surface acoustic wave linear motor　　　　　　　　　　　　　　　
  KOTANI Hiroyuki; TAKASAKI Masaya; ISHINO Yuji; MIZUNO Takeshi
  Volume：2006, Number：12, First page：67, Last page：68, 09 Mar. 2006
  Surface acoustic wave (SAW) linear motor is a kind of ultrasonic motors. The advantages of the SAW linear motor is thin structure, high thrust force, high velocity and precise positioning. Relationship between applied voltage and output velocity, however, has non-linearity in a low-velocity area due to friction drive principle. Therefore the SAW linear motor cannot obtain stable driving without feedback control in the low-velocity area. Previously, to realize such low velocity, PWM control and flexible slider structure were employed. Flexible structure was installed to cancel vibration due to PWM carrier frequency. In this research, we change calculation algorithm for slider velocity measurement. As a result, SAW linear motor can be driven at a low velocity of 0.05mm/s.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110006638512, CiNii Books ID：AA11902161
• 21009 Development of a Three-axis Active Magnetic Bearing Using the Motion Control of Permanent Magnets : 2nd report : Improvement of the experimental apparatus and basic experiments　　　　　　　　　　　　　　　
  Hirai Y.; Ishino Y.; Takasaki M.; Mizuno T.
  Volume：2006, Number：12, First page：69, Last page：70, 09 Mar. 2006
  A new repulsive-type magnetic bearing system is developed which uses the motion control of a permanent magnet for the stabilization of an axial motion and two radial motions. The developed actuator units for motion control are studied experimentally. Stabilization is tried when the motion of the floator is mechanically constrained.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110006638513, CiNii Books ID：AA11902161
• 518 Micro Gyroscopic Sensor using Active Magnetic Bearing : 1st Report: Principle of Detecting Angular Velocity and Basic Experiments　　　　　　　　　　　　　　　
  MARUYAMA Yutaka; TAKASAKI Masaya; ISHINO Yuji; MIZUNO Takeshi; ISHIGAMI Takayuki; KAMENO Hironori
  Dynamics & Design Conference, First page："518, Last page：1"-"518-4", 2006
  The paper proposes to apply Active Magnetic Bearing (AMB) for developing compact, multi-axis, high-accuracy and low-cost gyroscopic sensors. In the proposed sensor, angular velocity and in addition acceleration are measured based on the control signal for maintaining the relative position of the shaft to the stator in the AMB. It works as two-axis gyroscopic sensor and in addition three-axis servo-type accelerator so that the cost performance of the proposed sensor is expected to be high enough. In order to investigate its feasibility, several basic studies are carried out with a conventional-size AMB.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110006656402, CiNii Books ID：AA12120184
• 診断機能を備えた歯科用超音波スケーラの開発(<小特集>運動と振動の制御の21世紀への新展開)　　　　　　　　　　　　　　　
  丸山 裕; 高崎 正也; 久田見 朋範; 水野 毅
  日本機械学會論文集. C編, Volume：72, Number：721, First page：2727, Last page：2731, 2006
  DOI：https://doi.org/10.1299/kikaic.72.2727
  DOI ID：10.1299/kikaic.72.2727, ISSN：0387-5024, CiNii Articles ID：110004811589
• 磁路制御形磁気浮上の提案と基礎実験　　　　　　　　　　　　　　　
  水野毅; 星野博; 高崎正也; 石野裕
  Volume：14, Number：3, First page：346, Last page：352, 2006
• Active Type Surface Acoustic Wave Tactile Display　　　　　　　　　　　　　　　
  TAKASAKI Masaya; KOTANI Hiroyuki; ENDO Takeshi; NARA Takaaki; MIZUNO Takeshi
  Transactions of the Society of Instrument and Control Engineers, Volume：4 (17年度), Number：4, First page：327, Last page：333, 2006
  Reproduction of human haptic sensation has lately attracted attention for various fields, such as virtual reality, remote control of robots, computer interfaces and so on. Previously, a novel method to provide human tactile sensation using surface acoustic wave (SAW) was proposed. A pulse modulated driving voltage excites temporal distribution of standing SAW on a stator transducer. The distribution generated fluctuating friction on the surface of SAW substrate. When the surface with burst SAW is explored by fingertip through a slider, the fluctuation can be transformed into vibration and perceived as tactile sensation at mechanoreceptors in our finger skin. A prototype of the SAW tactile display is fabricated according to the principle. Rubbing the substrate through the slider, we can feel tactile sensations under a control depending on the rubbing motion. A controller for the prototype is developed. For evaluation of slider steel ball vibration, steel ball velocity under the control is measured. Two sets of the control parameters are selected so that operators can discriminate two kinds of roughness sensation. Effectiveness of the selection is evaluated through an experiment with a large number of subjects.
  The Society of Instrument and Control Engineers
  DOI：https://doi.org/10.9746/sicetr1965.42.327
  DOI ID：10.9746/sicetr1965.42.327, ISSN：0453-4654, CiNii Articles ID：130003971555
• 磁路制御形磁気浮上の提案と基礎実験　　　　　　　　　　　　　　　
  水野毅; 星野博; 高崎正也; 石野裕
  日本AEM学会誌, Volume：14, Number：3, First page：346, Last page：352, 2006
• アクティブタイプ弾性表面波皮膚感覚ディスプレイによる情報提示への応用に関する研究　　　　　　　　　　　　　　　
  高崎正也
  総合研究機構研究プロジェクト研究成果報告書, Volume：4 (17年度), Number：4, First page：327, Last page：333, 2006
  Reproduction of human haptic sensation has lately attracted attention for various fields, such as virtual reality, remote control of robots, computer interfaces and so on. Previously, a novel method to provide human tactile sensation using surface acoustic wave (SAW) was proposed. A pulse modulated driving voltage excites temporal distribution of standing SAW on a stator transducer. The distribution generated fluctuating friction on the surface of SAW substrate. When the surface with burst SAW is explored by fingertip through a slider, the fluctuation can be transformed into vibration and perceived as tactile sensation at mechanoreceptors in our finger skin. A prototype of the SAW tactile display is fabricated according to the principle. Rubbing the substrate through the slider, we can feel tactile sensations under a control depending on the rubbing motion. A controller for the prototype is developed. For evaluation of slider steel ball vibration, steel ball velocity under the control is measured. Two sets of the control parameters are selected so that operators can discriminate two kinds of roughness sensation. Effectiveness of the selection is evaluated through an experiment with a large number of subjects.
  The Society of Instrument and Control Engineers
  DOI：https://doi.org/10.9746/sicetr1965.42.327
  DOI ID：10.9746/sicetr1965.42.327, ISSN：0453-4654, CiNii Articles ID：130003971555
• B33 VIBRATION ISOLATION SYSTEM USING ZERO-POWER MAGNETIC SUSPENSION : 6^ REPORT: EXPERIMENTAL STUDY ON SYSTEM WITH A WEIGHT SUPPORT MECHANISM　　　　　　　　　　　　　　　
  HOQUE Emdadul; DAISUKE Kishita; TAKASAKI Masaya; ISHINO Yuji; MIZUNO Takeshi
  Dynamics and Design Conference, Volume：2005, Number：9, First page：340, Last page：344, 22 Aug. 2005
  A vibration isolation system with weight support mechanism using zero-power control is presented in this paper. Zero-compliance to direct disturbance of the system can be achieved by connecting a normal spring in series with a spring of negative stiffness by zero-power control. To improve the performance of the system for direct disturbance, a weight support mechanism is introduced. In this research, analytical and experimental studies have been conducted to measure the effectiveness of the isolation system. It is showed that the system is capable to realize negative stiffness as well as to suppress the disturbances even using such additional mechanism.
  The Japan Society of Mechanical Engineers, English
  CiNii Articles ID：110006209536, CiNii Books ID：AA11902241
• 616 Speed Control of SAW Linear Motor　　　　　　　　　　　　　　　
  KOTANI Hiroyuki; TAKASAKI Masaya; ISHINO Yuji; MIZUNO Takeshi
  Dynamics & Design Conference, Volume：2005, First page："616, Last page：1"-"616-4", 22 Aug. 2005
  Surface acoustic wave (SAW) linear motor, which is a kind of ultrasonic motor, had many advantages such as high force, high speed and precise positioning. Relationship between motor speed and input voltage, however, had nonlinearity at lower speed due to its friction drive principle. Thus SAW linear motor could not obtain a stable drive at the low speed area. In this research, PWM (Pulse width modulation) was applied for controlling the slider speed. Lower speed in non-linearity area was realized. Furthermore precise positioning was also discussed.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110006655314, CiNii Books ID：AA12120184
• 620 An Active Six-axis Vibration Isolation System with a Parallel Mechanism Using Zero-power Magnetic Suspension　　　　　　　　　　　　　　　
  ISHIGAMI Takayuki; ISHINO Yuji; TAKASAKI Masaya; TOMIYA Takefumi
  Dynamics & Design Conference, Volume：2005, First page："620, Last page：1"-"620-5", 22 Aug. 2005
  A new active six-axis vibration isolation system is proposed which uses zero-power magnetic suspension and a parallel mechanism. It consists of six direct acting links, a table and a base. An active single-axis vibration isolation unit equipped with zero-power magnetic suspension works as a direct acting link. Several experiments are carried out with the developed vibration isolation units.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110006655318, CiNii Books ID：AA12120184
• 221 AN ACTIVE MICROVIBRATION ISOLATOR WITH MAGNETIC SUSPENSION TECHNOLOGY(General Session III) :　　　　　　　　　　　　　　　
  HOQUE Emdadul; TAKASAKI Masaya; ISHINO Yuji; MIZUNO Takeshi
  VS tech : the ... International Symposium on Advanced Technology of Vibration and Sound, Volume：2005, First page：299, Last page：304, 2005
  An active three-degree-of-freedom vibration isolator using zero-power magnetic suspension was developed to attenuate the effect of direct disturbances and to isolate vibrations transmitted from the ground. The zero-compliance of the isolator for direct disturbances was realized by connecting a conventional spring in series with an active suspension mechanism. In this research, analytical and experimental studies have been conducted to measure the effectiveness of the isolator under both types of disturbances. The transmissibility characteristics of the isolator from the floor showed that the vibration isolation performance could be improved by selecting suitable parameters of the zero-power controller and the damping between the base to middle table.
  English
  CiNii Articles ID：110006185963, CiNii Books ID：AA12120162
• 研究プロジェクト「マイクロ／ナノスケール計測制御テクノセンタ ー」活動報告<研究成果報告>　　　　　　　　　　　　　　　
  水野毅; 川橋正昭; 大八木重治; 加藤寛; 佐藤勇一; 堀尾健一郎; 豊岡了; 荒居善雄; 綿貫啓一; 池野順一; 小原哲郎; 高崎正也
  Volume：1, Number：38, First page：114, Last page：118, 2005
• エネルギ伝送機能を備えた永久磁石併用交流形磁気浮上　　　　　　　　　　　　　　　
  水野毅; 木下大輔; 高崎正也; 石野裕二
  Volume：13, Number：4, First page：322, Last page：327, 2005
• 研究プロジェクト「マイクロ／ナノスケール計測制御テクノセンタ ー」活動報告<研究成果報告>
  水野毅; 川橋正昭; 大八木重治; 加藤寛; 佐藤勇一; 堀尾健一郎; 豊岡了; 荒居善雄; 綿貫啓一; 池野順一; 小原哲郎; 高崎正也
  埼玉大学紀要, 工学部, 第1部論文集, Volume：1, Number：38, First page：114, Last page：118, 2005
  This report describes the outline and activities of the research project entitled by "Techno Center for Micro/Nano-Scale Control and Measurement". The research group consists of twelve members, most of which belong to the Department of Mechanical Engineering, Saitama University. The research topics of each member are presented, followed by two articles on micro-scale fluid measurement and high-precision vibration isolation system.
  Japanese
  ISSN：1880-4446, CiNii Articles ID：120001370521
• エネルギ伝送機能を備えた永久磁石併用交流形磁気浮上　　　　　　　　　　　　　　　
  水野毅; 木下大輔; 高崎正也; 石野裕二
  日本AEM学会誌, Volume：13, Number：4, First page：322, Last page：327, 2005
• Zero-Compliance System Using Negative Stiffness (4th report: System Using Pneumatic Actuators)　　　　　　　　　　　　　　　
  MIZUNO Takeshi; TAKASAKI Masaya; ISHINO Yuji; MURASHITA Masato
  Volume：2004, Number：10, First page：227, Last page：228, 03 Mar. 2004
  The vibration isolation system using negative stiffness realized by active control technique was studied experimentally. An apparatus with two pneumatic actuators was developed. The actuators were used for realizing negative stiffness and for adjusting positive stiffness and damping characteristics, respectively. It was experimentally confirmed that the equalization of the amplitude of negative and positive stiffness enabled the system to have zero-compliance against direct disturbance.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110004058621, CiNii Books ID：AA11902161
• Flux Path Control Magnetic Suspension : 3rd report : Control of Lateral Motion　　　　　　　　　　　　　　　
  MIZUNO Takeshi; HOSHINO Hiroshi; TAKASAKI Masaya; ISHINO Yuji
  Dynamics and Design Conference, Volume：2003, Number：8, First page：163, Last page：165, 30 Oct. 2003
  An experimental apparatus is developed for study on a new magnetic suspension method in which the attractive force of a permanent magnet is adjusted by a flux path control mechanism. The apparatus has a two-dimensional flux path control mechanism that enables the three-dimensional positioning of the suspension object. It is shown experimentally that the developed apparatus can achieve such positioning control.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110002502056, CiNii Books ID：AA11902241
• Zero-Compliance System Using Negative Stiffness 3rd report : Efficacy of Feedforward Control　　　　　　　　　　　　　　　
  MIZUNO Takeshi; SHIROTA Terumasa; TAKASAKI Masaya; ISHINO Yuji
  Dynamics and Design Conference, Volume：2003, Number：8, First page：531, Last page：535, 30 Oct. 2003
  The vibration isolation system using negative stiffness realized by active control technique was studied experimentally. An apparatus with two voice coil motors was developed; they were used for realizing negative stiffness and for adjusting positive stiffness and damping characteristics, respectively. The equalization of the amplitude of negative and positive stiffness enabled the system to have zero-compliance against direct disturbance. A feedforward control was introduced for improving the transient response to stepwise direct disturbance. The efficacy was confirmed experimentally.
  The Japan Society of Mechanical Engineers, Japanese
  CiNii Articles ID：110002502136, CiNii Books ID：AA11902241
• REALIZATION OF NEGATIVE STIFFNESS USING AN AIR ACTUATOR　　　　　　　　　　　　　　　
  MIZUNO Takeshi; MURASHITA Masato
  Volume：2003, First page：76, Last page：76, 15 Sep. 2003
  This paper shows a control method which enables a suspension mechanism with an air actuator to have negative stiffness. An experimental apparatus is manufactured for experimental study, in which the table is suspended and drived by an air actuator. Applying the proposed control method to this apparatus, we have confirmed that the steady-state displacement of the table is in the direction opposite to load, that is, the system has negative stiffness.
  The Japan Society of Mechanical Engineers, Japanese
  ISSN：1348-0235, CiNii Articles ID：110002483176, CiNii Books ID：AA11901770
• Flux Path Control Magnetic Suspension : 1st report : Principles of Suspension　　　　　　　　　　　　　　　
  Mizuno Takeshi; Hirota Satoru; Takasaki Masaya; Ishino Yuji
  Volume：2002, First page：177, Last page：178, 2002
  Japanese
  CiNii Articles ID：110002500655, CiNii Books ID：AA11902219
• Surface acoustic wave tactile display　　　　　　　　　　　　　　　
  T Nara; M Takasaki; T Maeda; T Higuchi; S Ando; S Tachi
  IEEE COMPUTER GRAPHICS AND APPLICATIONS, Volume：21, Number：6, First page：56, Last page：63, Nov. 2001
  We propose a tactile display using surface acoustic waves. We can change continuously change the fineness of the surface's grain by controlling the SAWs' burst frequency.
  IEEE COMPUTER SOC, English
  DOI：https://doi.org/10.1109/38.963461
  DOI ID：10.1109/38.963461, ISSN：0272-1716, eISSN：1558-1756, CiNii Articles ID：30019935372, Web of Science ID：WOS:000171739600009
• Study on larger output force of a surface acoustic wave linear motor　　　　　　　　　　　　　　　
  TAKASAKI Masaya; KUROSAWA Minoru; HIGUCHI Toshiro; Masaya TAKASAKI; Minoru KUROSAWA; Toshiro HIGUCHI
  Volume：9, Number：2, First page：189, Last page：194, 2001
  This paper deals with improvement in performance of a surface acoustic wave (SAW) linear motor. The relationship between the motor output force and silicon slider design was investigated. The slider that has the smaller projections and uniform distribution of the projections exhibited higher performance. By using the optimized silicon slider, the motor was driven at the output force of 6.4 N. A larger silicon slider, which can perform larger output force, was also discussed, for a larger slider has larger contact area. When a silicon slider which is longer along SAW propagation is driven, dump of SAW due to driving the slider is observed.
  Japanese
  ISSN：0919-4452, CiNii Articles ID：110003828872, CiNii Books ID：AN10457520
• 弾性表面波リニアモータの高出力化の検討　　　　　　　　　　　　　　　
  高崎正也; 黒澤実; 樋口俊郎
  日本AEM学会誌, Volume：9, Number：2, First page：189, Last page：194, 2001
  This paper deals with improvement in performance of a surface acoustic wave (SAW) linear motor. The relationship between the motor output force and silicon slider design was investigated. The slider that has the smaller projections and uniform distribution of the projections exhibited higher performance. By using the optimized silicon slider, the motor was driven at the output force of 6.4 N. A larger silicon slider, which can perform larger output force, was also discussed, for a larger slider has larger contact area. When a silicon slider which is longer along SAW propagation is driven, dump of SAW due to driving the slider is observed.
  Japanese
  ISSN：0919-4452, CiNii Articles ID：110003828872, CiNii Books ID：AN10457520
• Optimum contact conditions for miniaturized surface acoustic wave linear motor　　　　　　　　　　　　　　　
  M Takasaki; MK Kurosawa; T Higuchi
  ULTRASONICS, Volume：38, Number：1-8, First page：51, Last page：53, Mar. 2000
  This paper reports the successful operation of a 70 MHz driving surface acoustic wave (SAW) linear motor with a miniaturized stator transducer. This paper also deals with an investigation into an optimized slider design for the miniaturized SAW linear motor. The performance of three silicon type sliders, with different projection size, was compared. Output forces of the three sliders were measured with change of pre-load. It was found that the slider with smaller projection tended to produce greater output force. (C) 2000 Elsevier Science B.V. All rights reserved.
  ELSEVIER SCIENCE BV, English
  DOI：https://doi.org/10.1016/S0041-624X(99)00093-1
  DOI ID：10.1016/S0041-624X(99)00093-1, ISSN：0041-624X, CiNii Articles ID：80011701817, PubMed ID：10829627, Web of Science ID：WOS:000086662100011
• Miniaturization of surface acoustic wave linear motor　　　　　　　　　　　　　　　
  TAKASAKI Masaya; KUROSAWA Minoru Kuribayashi; HIGUCHI Toshiro
  Micromechatronics, Volume：44, Number：3, First page：11, Last page：17, 2000
  This paper describes the way of miniaturization of a surface acoustic wave(SAW)linear motor and characteristics of the miniaturized motor. A stator transducer can be miniaturized by operation at higher frequency. The miniaturized SAW linear motor could be successfully driven at the operating frequency of 50 MHz and 70 MHz. The limit of miniaturization, namely driving frequency limit, is also discussed. It seemsthat the limit depends on the surface roughness of the stator transducer.
  The Horological Institute of Japan, English
  DOI：https://doi.org/10.20805/micromechatronics.44.3_11
  DOI ID：10.20805/micromechatronics.44.3_11, ISSN：1343-8565, CiNii Articles ID：110002687164, CiNii Books ID：AA11546384
• 弾性表面波リニアモータの小型化に関する研究　　　　　　　　　　　　　　　
  高崎正也; 黒澤実; 樋口俊郎
  マイクロメカトロニクス, Volume：44, Number：3, First page：11, Last page：17, 2000
  This paper describes the way of miniaturization of a surface acoustic wave(SAW)linear motor and characteristics of the miniaturized motor. A stator transducer can be miniaturized by operation at higher frequency. The miniaturized SAW linear motor could be successfully driven at the operating frequency of 50 MHz and 70 MHz. The limit of miniaturization, namely driving frequency limit, is also discussed. It seemsthat the limit depends on the surface roughness of the stator transducer.
  The Horological Institute of Japan, English
  DOI：https://doi.org/10.20805/micromechatronics.44.3_11
  DOI ID：10.20805/micromechatronics.44.3_11, ISSN：1343-8565, CiNii Articles ID：110002687164, CiNii Books ID：AA11546384
• Optimum Contact Conditions for Miniaturized SAW Motor　　　　　　　　　　　　　　　
  Masaya Takasaki; Minoru K. Kurosawa; Toshiro Higuchi
  Ultrasonics, Volume：38, Number：1/8, First page：51, Last page：53, 2000
  DOI：https://doi.org/10.1016/S0041-624X(99)00093-1
  DOI ID：10.1016/S0041-624X(99)00093-1, ISSN：0041-624X, CiNii Articles ID：80011701817, PubMed ID：10829627
• A surface-acoustic-wave gyro sensor　　　　　　　　　　　　　　　
  M Kurosawa; Y Fukuda; M Takasaki; T Higuchi
  SENSORS AND ACTUATORS A-PHYSICAL, Volume：66, Number：1-3, First page：33, Last page：39, Apr. 1998
  This paper explains two novel methods to detect angular velocity by using a surface-acoustic-wave (SAW) device. In both methods, Coriolis forces, which act on the particles vibrating in the standing wave of a SAW, are applied. A novel gyro sensor is planned based on one of the two methods. For accurate fabrication, the dimensions of the electrodes are designed by using equivalent-circuit models. A SAW gyro sensor using a Rayleigh wave that propagated on a 128 degrees Y-cut LiNbO3 3 inch wafer with an operating frequency of 15 MHz has been designed and fabricated on trial. (C) 1998 Elsevier Science S.A. All rights reserved.
  ELSEVIER SCIENCE SA, English
  ISSN：0924-4247, Web of Science ID：WOS:000073204000006
• A surface-acoustic-wave gyro sensor　　　　　　　　　　　　　　　
  M Kurosawa; Y Fukuda; M Takasaki; T Higuchi
  SENSORS AND ACTUATORS A-PHYSICAL, Volume：66, Number：1-3, First page：33, Last page：39, Apr. 1998
  This paper explains two novel methods to detect angular velocity by using a surface-acoustic-wave (SAW) device. In both methods, Coriolis forces, which act on the particles vibrating in the standing wave of a SAW, are applied. A novel gyro sensor is planned based on one of the two methods. For accurate fabrication, the dimensions of the electrodes are designed by using equivalent-circuit models. A SAW gyro sensor using a Rayleigh wave that propagated on a 128 degrees Y-cut LiNbO3 3 inch wafer with an operating frequency of 15 MHz has been designed and fabricated on trial. (C) 1998 Elsevier Science S.A. All rights reserved.
  ELSEVIER SCIENCE SA, English
  ISSN：0924-4247, Web of Science ID：WOS:000073204000006

• 弾性表面波皮膚感覚ディスプレイ　　　　　　　　　　　　　　　
  2001
  Competitive research funding
• Surface Acoustic Wave Tactile Display　　　　　　　　　　　　　　　
  2001
  Competitive research funding