Ohnishi, Kouhei



Keio Frontier Research & Education Collaborative Square (K-FRECS), K-FRECS at Shin-Kawasaki (Mita)


Project Professor (Non-tenured)

External Links

Career 【 Display / hide

  • 1980.04

    慶應義塾大学工学部電気工学科 ,助手

  • 1982.04

    慶應義塾大学工学部電気工学科 ,専任講師

  • 1988.04

    慶應義塾大学理工学部電気工学科 ,助教授

  • 1992.04

    兼慶應義塾大学就職部(矢上支部) ,委員

  • 1993.10

    慶應義塾大学学生部(矢上) ,委員

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Academic Background 【 Display / hide

  • 1975.03

    The University of Tokyo, Faculty of Engineering, 電気工学科

    University, Graduated

  • 1977.03

    The University of Tokyo, Graduate School, Division of Engineering, 電気工学専門課程

    Graduate School, Completed, Master's course

  • 1980.03

    The University of Tokyo, Graduate School, Division of Engineering, 電気工学専門課程

    Graduate School, Completed, Doctoral course

Academic Degrees 【 Display / hide

  • 工学 , The University of Tokyo, 1980.03


Books 【 Display / hide

  • Mechatronics and Robotics: New Trends and Challenges

    Ohnishi K., et al, CRC Press, 2020.11,  Page: 266

    Scope: 12 Human–Robot Interaction

  • Motion Control Systems


    Scope: 364

  • 「コンピュータの数理」

    矢向 高弘,村上 俊之,大西 公平 , 朝倉書店, 2000.10

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  • 丸善

    堀 洋一、大西公平, 1998.06

  • 「制御工学の基礎」

    堀 洋一、 大西公平, 丸善, 1997.10

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Papers 【 Display / hide

  • Stability and Robustness of the Disturbance Observer-Based Motion Control Systems in Discrete-Time Domain

    Sariyildiz E., Hangai S., Uzunovic T., Nozaki T., Ohnishi K.

    IEEE/ASME Transactions on Mechatronics (IEEE/ASME Transactions on Mechatronics)  26 ( 4 ) 2139 - 2150 2021.08

    ISSN  10834435

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    This article analyses the robust stability and performance of the disturbance observer (DOb) based digital motion control systems in the discrete-time domain. It is shown that the phase margin and the robustness of the digital motion controller can be directly adjusted by tuning the nominal plant model and the bandwidth of the observer. However, they have the upper and lower bounds due to robust stability and performance constraints as well as the noise sensitivity. The constraints on the design parameters of the DOb change when the digital motion controller is synthesized by measuring different states of a servosystem. For example, the bandwidth of the DOb is limited by the noise sensitivity and waterbed effect when the velocity and position measurements are employed in the digital robust motion controller synthesis. The robustness constraint due to the waterbed effect is removed when the DOb is implemented by acceleration measurement. The design constraints on the nominal plant model and the bandwidth of the observer are analytically derived by employing the generalized Bode integral theorem in discrete time. The proposed design constraints allow one to systematically synthesize a high-performance DOb-based digital robust motion controller. The experimental results are given to verify the proposed analysis and synthesis methods.

  • Multi functional drill incorporating linear motor for haptic surgical instrument and simulator

    Matsunaga T., Shimono T., Ohnishi K., Takano S., Kobayashi H., Yagi M., Nakamura M.

    2021 IEEE International Conference on Mechatronics, ICM 2021 (2021 IEEE International Conference on Mechatronics, ICM 2021)   2021.03

    ISSN  9781728144429

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    In orthopedic surgery, tasks to cut the vertebra by surgical drills involve the risk of the spinal cord injury. Since the spinal cord injury causes motor and sensory disorder to patients, orthopedists who perform spine surgery must have skills to achieve tasks using surgical drills. Although robotic technologies is being applied to orthopedic surgical operations, support for surgeons in delicate tasks requiring surgeon's skills is insufficient. In this study, a multi functional drill available for both a surgical instrument and a simulator is presented. A linear motor incorporated in the proposed device used as a surgical instrument provides support for operators, while measuring position information and estimating force information. Furthermore, environmental information can be abstracted by haptic information such as position and force information. Virtual environment reproduced by the environmental information is presented by the proposed device used as a simulator. The feasibility of the multi functional drill is confirmed by utilizing functions as a surgical instrument and a simulator.

  • Development of multi degrees-of-freedom haptic forceps robot with three actuated fingers

    Matsunaga T., Shimono T., Ohnishi K.

    IEEJ Journal of Industry Applications (IEEJ Journal of Industry Applications)  10 ( 2 ) 247 - 253 2021.03

    ISSN  21871094

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    Surgical robots have been studied and developed to assist surgeons. Master-slave flexible forceps robots that are components of a flexible endoscopic surgical robot are useful to realize novel minimally invasive surgical procedures that are difficult for conventional rigid medical devices. Although driving force for the tip portion of a flexible forceps robot is mechanically transmitted by wires through the flexible portion, friction and backlash changed by the posture of the flexible portion make it difficult to realize precise end effector control. Furthermore, transmission of haptic sensation is necessary to realize safer operation. In this study, a multi degrees-of-freedom (DoF) haptic forceps robot with three fingers is presented as an end effector of a flexible forceps robot. Transmission of driving force in flexible structure that causes performance deterioration is eliminated by arranging motors near the end effector. To transmit haptic sensation to operators, bilateral control is implemented to a master-slave system composed of the haptic forceps robot and a multi DoF input device. Additionally, control on modal space is implemented to verify finger dexterity. The utility of the haptic forceps robot is experimentally validated.

  • Bilateral teleoperatìon system with extension of information based on visual information

    Matsunaga T., Shimono T., Ohnishi K.

    Seimitsu Kogaku Kaishi/Journal of the Japan Society for Precision Engineering (Seimitsu Kogaku Kaishi/Journal of the Japan Society for Precision Engineering)  87 ( 4 ) 380 - 387 2021

    ISSN  09120289

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    Master-slave teleoperatìon robots are useful for tasks that require human judgments and skills. Haptic sensation can be transmitted between a master and a slave by implementing bilateral control. Besides, visual information of the slave side that cannot be directly seen from the master side is presented by devices such as cameras, endoscopes, and displays. Therefore, advanced support of the teleoperatìon robots for operators can be expected by utilizing extended visual and haptic information. In this paper, a master-slave teleoperation system with ability to extend information transmitted to operators is proposed. The teleoperation system consists of one degree of freedom master-slave system implementing bilateral control based on robust acceleration control and an image processing system. To support operators, visual and haptic augmented reality is generated by image processing, micro-macro bilateral control, and compliance control. In addition, a design method of position and force scaling for micro-macro bilateral control according to magnification ratio of image is presented. The utility of the proposed bilateral teleoperation system is verified by experiments.

  • Online Motion Modification by Operator in Motion Reproduction System

    Sun X., Nozaki T., Ohnishi K., Murakami T.

    IECON Proceedings (Industrial Electronics Conference) (IECON Proceedings (Industrial Electronics Conference))  2020-October   668 - 673 2020.10

    ISSN  9781728154145

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    © 2020 IEEE. This paper proposes a novel online motion modification method in motion reproduction system. Motion reproduction is used to reproduce human motion saved through bilateral control. Bilateral control is a teleoperation which can transmit both position and force. Human judgement is needed for compensating the saved motion when the environment is different. However, conventional motion reproduction system only relies on saved motion or environment in slave side. Therefore operators in master side cannot modify the motion after motion has been saved. Instead of just reproducing the motion data, the proposed method adds master system at motion reproduction phase so that an operator can modify the motion. If the master system is simply added to motion reproduction system, the operator's motion and saved motion will interfere each other. Therefore, we propose to use weightings to suppress the interference. Simulated results validates the effectiveness of the proposal.

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Papers, etc., Registered in KOARA 【 Display / hide

Reviews, Commentaries, etc. 【 Display / hide

Presentations 【 Display / hide

  • 精子形成能判定のための精巣の硬さ測定装置の開発~ハムスター精巣を用いての検討


    日本コンピュータ外科学会 (東京、日本) , 2016.11, Oral Presentation(general), 日本コンピュータ外科学会

  • The Control Scheme of Underactuated Master System in Bilateral Control for Operation of Fragile Environment


    The 41st Annual Conference of IEEE Industrial Electronics Society,IECON (横浜) , 2016.11, Oral Presentation(general), IECON

  • Development of haptic prosthetic hand for realization of intuitive operation


    The 42nd Annual Conference of the IEEE Industrial Electronics Society,IECON 2016 (Firenze,Italy) , 2016.10, Oral Presentation(general), IEEE

  • Simultaneonus Locomation of Biped Robot with the Transmission of Human Motion


    The 42nd Annual Conference of the IEEE Industrial Electrnics Society,IECON 2016 (Firenze,Italy) , 2016.10, Oral Presentation(general), IEEE

  • Robotic Finger Rehabilitation System for Stroke Patient Using Surface EMG Armband


    The 42nd Annual Conference of the IEEE Industrial Electronics Society,IECON 2016 (Firenze Italy) , 2016.10, IEEE

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Research Projects of Competitive Funds, etc. 【 Display / hide

  • Real haptics system without any sensors at slave side


    MEXT,JSPS, Grant-in-Aid for Scientific Research, 大西 公平, Grant-in-Aid for Scientific Research (B), Principal Investigator

  • Revolution of integrated platform on medicine and engineering by haptic technology


    MEXT,JSPS, Grant-in-Aid for Scientific Research, 大西 公平, Grant-in-Aid for Scientific Research (S), Principal Investigator

Awards 【 Display / hide

  • Fujihara Award

    大西公平, 2019.06, 藤原科学財団

    Type of Award: International Academic Awards.  Country: 日本

  • 電気学会功績賞

    2017.06, 電気学会

    Type of Award: Awards of National Conference, Council and Symposium.  Country: 日本

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  • 紫綬褒章

    大西公平, 2016.11, Japanese Gavernment, 多年学術の分野においてよく努め発展に寄与したことについて

    Type of Award: Other Awards.  Country: Japan

  • 産業応用部門賞

    嶌本慶太・谷田和貴・野崎貴裕・大西公平, 2014.08, 電気学会, 腱駆動型球体間接機構による力覚伝達

    Type of Award: Awards of National Conference, Council and Symposium

  • 日本学術会議会長賞

    青山藤詞郎・柿沼康弘, 2013.09, 日本学術会議 産学官連携推進会議, 「外乱オブザーバー応用技術」の開発

    Type of Award: Awards of Publisher, Newspaper Company and Foundation.  Country: 日本

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Social Activities 【 Display / hide

  • IEEE 'Transactions on Industrial Electronics'


Memberships in Academic Societies 【 Display / hide

  • IEEE Industrial Electronics Society, 

  • Institute of Electrical Engineers of Japan, 

  • 日本コンピュータ外科学会, 

  • 電気学会, 

  • IEEE Industrial Electronics Society, 


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Committee Experiences 【 Display / hide

  • 2015.05

    会長, 電気学会

  • 2014.12

    委員, 電気学会実世界ハプティクスの高度化に関する協同研究委員会

  • 2014.05

    有識者会議役員, 電気学会

  • 2014.05

    会長代理, 電気学会理事会

  • 2014.02

    代議員, 電気学会

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