7-DOF外骨骼式上肢康复机器人整机静态误差分析

Static error analysis of 7-DOF exoskeleton upper limb rehabilitation robot

静态误差分析在7-DOF外骨骼式上肢康复机器人的设计、制造、装配中起着关键的作用,其结果影响着尺寸参数的选择和优化.对7-DOF外骨骼式上肢康复机器人末端运动规律进行了探究,通过理论计算得到末端位姿误差表达式,然后利用控制变量法来研究长度误差和角度误差对位姿的影响.借助MATLAB绘制出末端位姿误差曲线.经过比较分析发现角度误差比长度误差对康复机器人末端的位姿精度影响更大,所以在保证长度精度的同时尽可能提高角度的精度,从而减少加工成本和降低造成二次伤害的风险.

Static error analysis plays a significant role on design,manufacturing and assembly of 7-DOF exoskeleton upper limb rehabilitation robot. The result of static error analysis usually affects the choice of measurement and optimization. The end movement of 7-DOF exoskeleton upper limb rehabilitation robot was investigated. The expression of terminal position and orientation error was obtained by theoretical calculation,and control variate method was applied to investigate the influences of length error and angle error. The terminal position and orientation error curve was drawn by MATLAB. The comparison analysis shows that angle error has more enormous impact than that of length error on terminal position and orientation accuracy. The angle accuracy should be pledged as high as possible for reducing processing cost and lessening risk of secondary injury.