下肢康复训练机器人膝踝协调运动控制方法  

Knee Ankle Coordinated Motion Control Method for Lower Limb Rehabilitation Training Robot

作　　者：邢艳丽[1] 亢瑾 XING Yan-li;KANG Jin(Hengshui University,Hebei Hengshui 053000,China;North China University of Science and Technology,Hebei Tangshan 063210,China)

机构地区：[1]衡水学院,河北衡水053000 [2]华北理工大学,河北唐山063210

出　　处：《机械设计与制造》2022年第3期287-291,共5页Machinery Design & Manufacture

基　　金：河北省老年体育健康产业发展研究(201803040136)。

摘　　要：针对当前下肢康复训练机器人膝踝协调运动控制方法未考虑训练机器人系统不确定性,导致膝踝运动的速度与位置误差较高,收敛速度较慢,训练机器人步态不协调的问题,提出下肢康复训练机器人膝踝协调运动控制方法。设置标识点数量与具体位置,建立下肢刚体模型局部坐标系,分别构建不同点在矢状面的运动学方程,计算相邻点之间连线长度。利用膝踝等关节的动力学表达式,求出步态特征参数,通过高斯函数扩展形式,拟合膝关节转角非中心对称双峰曲线,采用分段曲线拟合形式,拟合踝关节转角参数,完成膝踝关节转角数学建模。采用自适应迭代学习控制算法,设立迭代控制信号,对膝踝运动轨迹跟踪,计算输出误差,确定自适应迭代条件,通过迭代项克服机器人系统带来的不确定性,实现膝踝协调运动控制。仿真实验表明,该方法的训练机器人膝踝运动步态较为协调,具有较快的收敛速度,有效降低膝踝运动的速度与位置误差,确保膝踝协调运动。Aiming at the problem that the current control method of knee ankle coordinated motion of lower limb rehabilitation training robot didn’t consider the uncertainty of the training robot system,which led to higher error in the speed and position of knee ankle movement,and slower convergence speed as well as uncoordinated gait of training robot,a control method of knee ankle coordinated motion of lower limb rehabilitation training robot had been proposed. The number and location of identification points were set. The local coordinate system of lower limb rigid body model was established. The kinematics equations of different points in the sagittal section were constructed,and the connecting line length between adjacent points was calculated. The gait characteristic parameters were obtained by using the dynamic expression of knee and ankle joints. The non centrosymmetric bimodal curve of knee joint angle was fitted by Gaussian function expansion,and the ankle joint angle parameters were fitted by piecewise curve fitting to complete the mathematical modeling of knee and ankle joint angle. The adaptive iterative learning control algorithm was used in this paper. The iteration control signal was established. The trajectory of the knee and ankle was tracked.Based on this,the output error was calculated. The adaptive iteration conditions were determined. The uncertainty caused by the iterative robot system was overcome. Knee and ankle movements were reasonably controlled. The simulation results showed that the training robot’s knee and ankle movement gait in this method is more coordinated and had a faster convergence speed. This method can effectively reduced the speed and position error of the knee and ankle movement,and ensured the coordinated movement of the knee and ankle.

关 键 词：下肢康复训练机器人 膝踝协调运动 自适应迭代控制 刚体模型 步态特征 

分 类 号：TH16[机械工程—机械制造及自动化] TP212[自动化与计算机技术—检测技术与自动化装置]