下肢外骨骼膝关节优化及人机控制仿真

Optimization of Lower Limb Exoskeleton Knee Joint and Man-machine Control Simulation

为使所有人体差异的残疾和运动障碍患者术后达到舒适性康复的目的,避免患者穿戴下肢外骨骼多次尝试的困扰,提出一种快速获取人体步态优化算法,该算法首先以一人身高数据为例结合CGA数据,由四杆机构模拟人体膝关节运动,利用MATLAB优化算法得到四杆机构的杆长并得出人体膝关节的瞬心轨迹,将其应用于下肢外骨骼的可调膝关节使人体穿戴外骨骼组成人机模型,但人机耦合的膝关节角装配的机械误差较大。利用ADAMS和MATLAB-Simlink联合仿真的PID控制人机模型,使人机耦合模型的膝关节变化的角度误差尽可能减到最小。人机模型在优化后关节误差由2°减小至0.2°左右,使运动障碍患者在康复过程中达到人机交互舒适性的效果。

This study aims to help patients with different disabilities and movement disorders achieve comfortable rehabilitation after operation and avoid the trouble of wearing lower limb exoskeleton for many times.An algorithm that can quickly obtain human gait optimization is proposed.First,we take the height data of a person as an example and combine CGA data to simulate the movement of human knee joint by a four-bar mechanism.Next,MATLAB optimization algorithm is used to obtain the rod length of the four-bar mechanism and the instantaneous center trajectory of the human knee joint,which is applied to the adjustable knee joint of the lower limb exoskeleton.Then a man-machine model is made.However,the mechanical error of joint angle assembly with man-machine coupling is large.By using PID of ADAMS and MATLAB-Simlink co-simulation to control the man-machine model,the angle error of knee joint change in man-machine coupling model is minimized.The results show that the joint error of man-machine model is reduced from 2°to 0.2°after optimization.It can help patients with movement disorders achieve the effect of human-computer interaction comfort in the rehabilitation process.