Modeling and design on control system of lower limb rehabilitation exoskeleton robot

Abstract

Disable people requires the assistance of the motion, of their lower limbs to improve their movement ability. For patients with lower limb paralysis, spinal cord injury and other diseases, the use of the lower limb rehabilitation robot is to gain trajectory training, which is a good means of recovery. Among them, the passive control mode is to help patient's pre-adaptive training; which refers to the training of the patient's legs, that can be seen as a part of the exoskeleton leg walker, equivalent to the load exoskeleton robot, and ignoring leg muscles initiative. The description of the controller and simulations with the lower limb rehabilitation robot are presented in this paper. Firstly, the dynamics equations of lower extremity rehabilitation exoskeleton with people consisting of man-machine system are set up. Secondly the mathematical model of AC servo motor has been established. Then, according to the characteristics of the object model design, the corresponding proportion integral derivative (PID) controller; the model have also been built based on MATLAB/Simulink for lower limb rehabilitation exoskeleton robot control system simulation. This can decrease tracking errors to achieve desired trajectory. The results shows that, the trajectory tracking performance is excellent and the lower limb rehabilitation robot exoskeleton is capable of movement in accordance with the laws of human motion, so as to achieve the passive rehabilitation purpose.