下肢康复机器人按需辅助自适应控制方法

摘要

The control of lower limb rehabilitation robot mostly is lacking in human active participation during gait rehabilitation,which can not provide suitable assistance based on the human impairment level.A novel adaptive assistance control strategy according to human need is presented for lower limb rehabilitation robot.The rehabilitation degree of human subjects is learnt in real time following the tracking errors between the man-machine movement trajectory and the ideal rehabilitation trajectory,so that the rehabilitation robot can adaptively provide the assist-as-needed.The man-machine dynamic model of the lower limb rehabilitation robot system is established and the assist-as-needed controller of lower limb rehabilitation robot is designed.The simulation for the proposed algorithm is conducted and the experiment with healthy subjects is implemented on single mechanical leg prototype.The results show that the assist-as-needed controller can adaptively attenuate the assist torque of rehabilitation robot according to human rehabilitation level as long as the forgetting term remains non-zero to serve the purpose of assistance according to human need.%针对现有下肢康复机器人步态康复训练控制缺乏患者的主动参与、不能按患者的康复程度提供按需辅助的问题,提出了一种新的下肢康复机器人按需辅助自适应控制方法.该方法通过人机运动轨迹与理想康复目标轨迹的跟踪偏差实时学习受试者的康复程度,从而使康复机器人能根据受试者的康复程度,自适应地提供按需辅助.首先建立了下肢康复机器人的人机系统动力学模型,其次设计了按需辅助自适应控制器,最后进行了按需辅助控制仿真实验,并在单腿实物样机上对健康受试者进行了实验.结果表明:按需辅助自适应控制器在有遗忘因子项的情况下,能够根据轨迹跟踪偏差学习受试者的康复程度,自适应地衰减机器人对受试者的辅助力矩,满足按需辅助的目的.