Precision Cascade Force Control of Multi-DOF Hydraulic Leg Exoskeleton

Hydraulic exoskeleton is a kind of the human robot interaction system, which can augment the human performance in the application of heavy load carrying. Due to the existence of complicated multi-joint nonlinear dynamics and various uncertainties, traditional robust control of these systems is hard to be realized in most of the practical research. In this paper, an adaptive robust cascade force controller is proposed for 3-DOF hydraulic leg exoskeleton to achieve accurate tracking of human motion. Specifically, the control strategy includes two levels. The desired joint positions, which can be assumed as the human motion intent as well, are generated in the high-level by attenuating the integral of human–machine interaction force. And in the low-level, an observer-based MIMO motion controller is developed for 3-DOF dynamics to track the generated human motion intent accurately. Adaptive robust control algorithms are developed in both control levels to address the strongly coupled high-order dynamics under parametric uncertainties and uncertain disturbances. Comparative simulations show that the human–machine interaction force can be attenuated exactly and robust performance to various uncertainties can be guaranteed, validating the effectiveness of the proposed scheme.

[1]  M. Tomizuka,et al.  Control of Exoskeletons Inspired by Fictitious Gain in Human Model , 2009, IEEE/ASME Transactions on Mechatronics.

[2]  E. Paljug,et al.  Some important considerations in force control implementation , 1992, Proceedings 1992 IEEE International Conference on Robotics and Automation.

[3]  Chang-Soo Han,et al.  Human–robot cooperation control based on a dynamic model of an upper limb exoskeleton for human power amplification , 2014 .

[4]  Tianyou Chai,et al.  Nonlinear Disturbance Observer-Based Control Design for a Robotic Exoskeleton Incorporating Fuzzy Approximation , 2015, IEEE Transactions on Industrial Electronics.

[5]  R. Volpe,et al.  An experimental evaluation and comparison of explicit force control strategies for robotic manipulators , 1992, Proceedings 1992 IEEE International Conference on Robotics and Automation.

[6]  Daniel Vélez Día,et al.  Biomechanics and Motor Control of Human Movement , 2013 .

[7]  Chang-Soo Han,et al.  Human-robot cooperative control based on pHRI (Physical Human-Robot Interaction) of exoskeleton robot for a human upper extremity , 2012 .

[8]  Bin Yao,et al.  Accurate Motion Control of Linear Motors With Adaptive Robust Compensation of Nonlinear Electromagnetic Field Effect , 2013, IEEE/ASME Transactions on Mechatronics.

[9]  Yang Song,et al.  Cascade force control of lower limb hydraulic exoskeleton for human performance augmentation , 2016, IECON 2016 - 42nd Annual Conference of the IEEE Industrial Electronics Society.

[10]  Huijun Gao,et al.  Filter-Based Adaptive Vibration Control for Active Vehicle Suspensions With Electrohydraulic Actuators , 2016, IEEE Transactions on Vehicular Technology.

[11]  Bin Yao,et al.  $\mu$-Synthesis-Based Adaptive Robust Control of Linear Motor Driven Stages With High-Frequency Dynamics: A Case Study , 2015, IEEE/ASME Transactions on Mechatronics.

[12]  Masayoshi Tomizuka,et al.  Adaptive Control of Robot Manipulators in Constrained Motion , 1993, 1993 American Control Conference.

[13]  Bin Yao,et al.  Time Optimal Contouring Control of Industrial Biaxial Gantry: A Highly Efficient Analytical Solution of Trajectory Planning , 2017, IEEE/ASME Transactions on Mechatronics.

[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]  Homayoon Kazerooni,et al.  Control of a lower extremity exoskeleton for human performance amplification , 2003 .

[16]  Masayoshi Tomizuka,et al.  Adaptive robust control of SISO nonlinear systems in a semi-strict feedback form , 1997, Autom..

[17]  焦宗夏,et al.  A practical nonlinear adaptive control of hydraulic servomechanisms with periodic-like disturbances , 2015 .

[18]  Fanping Bu.  Nonlinear model based coordinated adaptive robust control of electro-hydraulic systems , 2001 .

[19]  Bin Yao,et al.  High performance adaptive robust control of nonlinear systems: a general framework and new schemes , 1997, Proceedings of the 36th IEEE Conference on Decision and Control.

[20]  Huijun Gao,et al.  Transient-Performance-Guaranteed Robust Adaptive Control and Its Application to Precision Motion Control Systems , 2016, IEEE Transactions on Industrial Electronics.

[21]  Masayoshi Tomizuka,et al.  Adaptive robust control of MIMO nonlinear systems in semi-strict feedback forms , 2001, Autom..

[22]  Xiaoou Li,et al.  PID admittance control for an upper limb exoskeleton , 2011, Proceedings of the 2011 American Control Conference.

[23]  Chuxiong Hu,et al.  Advanced GTCF-LARC Contouring Motion Controller Design for an Industrial X–Y Linear Motor Stage With Experimental Investigation , 2017, IEEE Transactions on Industrial Electronics.

[24]  Ya-Jun Pan,et al.  Integrated adaptive robust control for multilateral teleoperation systems under arbitrary time delays , 2016 .

[25]  Zongxia Jiao,et al.  Adaptive Control of Hydraulic Actuators With LuGre Model-Based Friction Compensation , 2015, IEEE Transactions on Industrial Electronics.

[26]  Yang Song,et al.  Adaptive Robust Cascade Force Control of 1-DOF Hydraulic Exoskeleton for Human Performance Augmentation , 2017, IEEE/ASME Transactions on Mechatronics.

[27]  Bin Yao,et al.  Observer based coordinated adaptive robust control of robot manipulators driven by single-rod hydraulic actuators , 2000, Proceedings 2000 ICRA. Millennium Conference. IEEE International Conference on Robotics and Automation. Symposia Proceedings (Cat. No.00CH37065).

[28]  George T.-C. Chiu,et al.  Adaptive robust motion control of single-rod hydraulic actuators: Theory and experiments , 1999, Proceedings of the 1999 American Control Conference (Cat. No. 99CH36251).

[29]  Ming Zhang,et al.  Performance-Oriented Precision LARC Tracking Motion Control of a Magnetically Levitated Planar Motor With Comparative Experiments , 2016, IEEE Transactions on Industrial Electronics.

[30]  Yacine Amirat,et al.  Observer-based active impedance control of a knee-joint assistive orthosis , 2015, 2015 IEEE International Conference on Rehabilitation Robotics (ICORR).

[31]  Umashankar Nagarajan,et al.  Integral Admittance Shaping for exoskeleton control , 2015, 2015 IEEE International Conference on Robotics and Automation (ICRA).