Trajectory Tracking Control of Omni-directional Wheeled Robot for Lower Limbs Rehabilitative Training
YANG Junyou1, BAI Dianchun1, WANG Shuoyu2, ZHAO Wenzeng1
1. School of Electrical Engineering, Shenyang University of Technology, Shenyang 110870, China;
2. Department of Intelligent Mechanical Systems Engineering, Kochi University of Technology Kochi, 7828502, Japan
Omni-directional wheeled robot for lower limbs rehabilitative training needs to track trajectory which is set by doctors.The uncertainties of the robot and the disturbances caused by trained patient affect the tracking performances. A nonlinear robust L2 controller is presented to solve disturbance rejection problems.Kinematics model of lower limbs rehabilitative training robot is presented,thereby,a kinematics model of the position error system is established.The tracking and uncertain disturbance rejection are formulated as an L2 control question to design control law with backstepping algorithm in a built storage function.A trajectory tracking controller meeting the disturbance rejection requirement is constructed. Simulation and experiment results show that the proposed controller is effective.
[1] Barbeau H,Norman K,Fung J,et al.Does neurorehabilitation play a role in the recovery of walking in neurological populations[J].Annals of the New York Academy of Sciences,1998,860(1):377-392.
[2] 陈仲武.我国现代康复医学事业的发展历程[J].中国康复理论与实践,2001,7(3):97-100.Chen Z W.Development of mordem rehabilitation medicine in China[J].Chinese Journal of Rehabilitation Theory and Pracrice,2001,7(3):97-100.
[3] Reinkensmeyer D J,Timoszyk W K,de Leon R D,et al.A robotic stepper for retraining locomotion in spinal-injured rodents[C]//IEEE International Conference on Robotics and Automation.Piscataway,NJ,USA:IEEE,2000:2889-2894.
[4] Bejczy A K.Towards development of robotic aid for rehabilitation of locomotion-impaired subjects[C]//lst Workshop on Robot Motion and Control.Piscataway,NJ,USA:IEEE,1999:9-16.
[5] Yang J Y,Bai D C,Bai S,et al.Design of mechanical structure and tracking control system for lower limbs rehabilitative training robot[C]//6th International Conference on Mechatronics and Automation.Piscataway.NJ,USA:IEEE,2009:1824-1829.
[6] Kim S D,Hyun C H,Cho Y W,et al.Tracking control of 3-wheels omni-directional mobile robot using fuzzy azimuth estimator[C]//10th WSEAS International Conference on Robotics,Control and Manufacturing Technology.Athens,Greece:WSEAS Press,2010:47-51.
[7] Purwin O,D'Andrea R.Trajectory generation and control for four wheeled omnidirectional vehicles[J].Robotics and Autonomous Systems,2006,54(1):13-22.
[8] Ferrara A,Rubagotti M.Sliding mode control of a mobile robot for dynamic obstacle avoidance based on a time-varying harmonic potential field[C]//ICRA Workshop on Planning,Perception and Navigation for Intelligent Vehicles.2007.
[9] Morbidi E Prattichizzo D.Sliding mode formation tracking control of a tractor and trailer-car system[C]//International Conference on Robotics:Science and Systems.Cambridge,MA,USA:MIT Press,2007:126-134.
[10] 闫茂德,吴肯云,贺昱曜.非完整移动机器人的自适应滑模轨迹跟踪控制[J].系统仿真学报,2007,19(3):579-581.Yan M D,Wu Q Y,He Y Y.Adaptive sliding mode tracking control of nonholonomic mobile robot[J].Journal of System Simulation,2007,19(3):579-581.
[11] Doyle J C,Glover K,Khargonekar P P,et al.State-space solutions to standard H《,2》 andH《,∞》 control problems[J].IEEE Transactions on Automatic Control,1989,34(8):831-847.