并联踝康复机器人的设计与运动性能评价

Design and Kinematic Performance Evaluation of Parallel Ankle Rehabilitation Robot

对于足下垂和马蹄足内/外翻患者,均需对踝关节进行大量、重复性的康复训练,踝康复机器人是弥补人工康复训练不足、降低医师工作强度的关键设备。将踝关节的解剖结构及运动特性考虑在内,提出并研制2-UPS/RRR型并联踝康复机器人样机,可保证人-机转动中心近似重合。同时,搭建了作用力/矩信息采集平台,实现踝关节的被动、主动及人机交互训练,提高了机器人、患者及医师之间的交互能力。建立了踝康复机器人的运动学模型,通过求解其位置逆解,得到了机器人的理论工作空间。借助机器人样机的3转动自由度,精确地测量得到踝关节全域范围内的生理运动范围。通过机器人样机的全范围自主运动,记录并获得装置的有效工作空间,机器人有效工作空间小于理论工作空间,有效工作空间的测量具有较大的实际意义。进一步,对比分析机器人样机的有效工作空间和踝关节生理运动范围可知,两者在踝全域运动范围内的吻合度可达95%,较好地保障了踝关节康复所需要的运动空间。基于并联踝康复机器人的量纲一速度雅可比矩阵,对机器人的可操作度、灵巧性等运动学性能进行了分析,结果表明踝康复机器人在工作空间内不存在奇异位形且具有良好的运动学性能。

The ankle rehabilitation exoskeleton is a critical equipment for foot drop and talipes valgus patients requiring extensive and repetitive rehabilitation training to make up deficiencies of the manual rehabilitation training and reduce the workload of rehabilitation physicians.According to the anatomical structure and motion characteristics of the ankle,an ankle rehabilitation robot with 2-UPS/RRR configuration has been proposed and developed which can realize the approximate coincidence between the centers of the ankle and the rehabilitation robot.Meanwhile,a force/torque information collection platform is constructed to improve the interactivity among the robot,patients and physicians.The kinematic model of this rehabilitation robot is established.The corresponding theoretical workspace is obtained through solving inverse kinematics.The physiological range of activity of the ankle is accurately measured in the whole movement area with the help of the 3-degree-of^freedom of the prototype.According to the autonomous motion of the prototype,the effective workspace is recorded and obtained.The effective workspace of the robot is less than the theoretical workspace.Furthermore,the results show that the percent of contact area in the effective workspace and the physiological range can reach 95%and the rehabilitation robot can provide enough space for the injured ankle.Finally,based on the velocity Jacobian matrix of the robot,the kinematic performance such as the maneuverability and dexterity is acquired.The results show that this rehabilitation robot has no singular position and processes good kinematic performance in the effective workspace.