Mechanism and Control of Knee Power Augmenting Device with Backdrivable Electro-Hydrostatic Actuator

Wearable robots that assist human mobility are actuated according to human intention. The estima- tion of the intention is difficult that the direct measurement is not possible. Especially the force control of the robot require quick response and highly non-repeatable. Biolog- ical signals such as electromyography are often used but they lack stability. Sensitivity function gain maximization is yet another approach, but high backdrivability is neces- sary to realize comfort, which was difficult in conventional gear driven actuators. In this paper, we apply backdrivable electro-hydrostatic actuator to realize intrinsic backdriv- ability, which is then enhanced with low-impedance con- troller consisting of inertia scaling and disturbance ob- server based friction compensation. Power augmenting controller was realized with sensitivity function gain maxi- mization. Numeric analysis and evaluation tests on actual prototype were carried out.

[1]  Hiroshi Kaminaga,et al.  Backdrivability analysis of Electro-Hydrostatic Actuator and series dissipative actuation model , 2010, 2010 IEEE International Conference on Robotics and Automation.

[2]  O. Lindahl,et al.  The "screw-home" movement in the knee-joint. , 1966, Acta orthopaedica Scandinavica.

[3]  Alessandro De Luca,et al.  Actuator failure detection and isolation using generalized momenta , 2003, 2003 IEEE International Conference on Robotics and Automation (Cat. No.03CH37422).

[4]  Hiroshi Kaminaga,et al.  Backdrivable miniature hydrostatic transmission for actuation of anthropomorphic robot hands , 2007, 2007 7th IEEE-RAS International Conference on Humanoid Robots.

[5]  Ryuichi Kaneko,et al.  Population Projections for Japan : 2006-2055 Outline of Results , Methods , and Assumptions , 2008 .

[6]  H. Kobayashi,et al.  Development of muscle suit and application to factory laborers , 2009, 2009 International Conference on Mechatronics and Automation.

[7]  Hiroshi Kaminaga,et al.  Anthropomorphic robot hand with hydrostatic cluster actuator and detachable passive wire mechanism , 2009, 2009 9th IEEE-RAS International Conference on Humanoid Robots.

[8]  Hiroshi Kaminaga,et al.  Development of backdrivable hydraulic joint mechanism for knee joint of humanoid robots , 2009, 2009 IEEE International Conference on Robotics and Automation.

[9]  Jerry E. Pratt,et al.  The RoboKnee: an exoskeleton for enhancing strength and endurance during walking , 2004, IEEE International Conference on Robotics and Automation, 2004. Proceedings. ICRA '04. 2004.

[10]  B J Makinson.  Research and Development Prototype for Machine Augmentation of Human Strength and Endurance. Hardiman I Project , 1971 .

[11]  Yoshiyuki Sankai,et al.  Control method of robot suit HAL working as operator's muscle using biological and dynamical information , 2005, 2005 IEEE/RSJ International Conference on Intelligent Robots and Systems.

[12]  Keijiro Yamamoto,et al.  Development of Power Assisting Suit for Assisting Nurse Labor , 2002 .

[13]  Hiroshi Kaminaga,et al.  Electro-hydrostatic actuators with Series Dissipative property and their application to power assist devices , 2010, 2010 3rd IEEE RAS & EMBS International Conference on Biomedical Robotics and Biomechatronics.

[14]  Lihua Huang,et al.  On the Control of the Berkeley Lower Extremity Exoskeleton (BLEEX) , 2005, Proceedings of the 2005 IEEE International Conference on Robotics and Automation.

[15]  Alin Albu-Schäffer,et al.  A passivity based Cartesian impedance controller for flexible joint robots - part I: torque feedback and gravity compensation , 2004, IEEE International Conference on Robotics and Automation, 2004. Proceedings. ICRA '04. 2004.

[16]  Carlos Canudas de Wit,et al.  A new model for control of systems with friction , 1995, IEEE Trans. Autom. Control..

[17]  Carlos Canudas de Wit,et al.  A survey of models, analysis tools and compensation methods for the control of machines with friction , 1994, Autom..

[18]  Clark J. Radcliffe,et al.  Robust nonlinear stick-slip friction compensation , 1991 .

[19]  Homayoon Kazerooni,et al.  Human induced instability in powered hand controllers , 1992, Proceedings 1992 IEEE International Conference on Robotics and Automation.

[20]  Colin D. Schauder,et al.  Current Control of Voltage-Source Inverters for Fast Four-Quadrant Drive Performance , 1982, IEEE Transactions on Industry Applications.

[21]  Hiroshi Kaminaga,et al.  Development of knee power assist using backdrivable electro-hydrostatic actuator , 2010, 2010 IEEE/RSJ International Conference on Intelligent Robots and Systems.

[22]  Alessandro De Luca,et al.  Friction observer and compensation for control of robots with joint torque measurement , 2008, 2008 IEEE/RSJ International Conference on Intelligent Robots and Systems.

[23]  Alessandro De Luca,et al.  Sensorless Robot Collision Detection and Hybrid Force/Motion Control , 2005, Proceedings of the 2005 IEEE International Conference on Robotics and Automation.