The Flexible Control Research Of Ankle Rehabilitation Parallel Robot Based On Impedance Control

Ankle rehabilitation robot is a kind of intelligent medical equipment,which assists patients with functional disordered ankle joint to complete rehabilitation training.It is an important part of the medical robot,which can greatly improve the rehabilitation efficiency and effect,so it's important to reduce the social and family burden.Being the research subject,the 3-RSS/S ankle rehabilitation parallel robot has three rotation degrees of freedom,which can achieve three directions of the rotary motion of human ankle.Above all,the paper's main work centring on the robot includes:(1)According to the function of the rehabilitation of parallel robot studied in the research group and rehabilitation training characteristics of injuried ankle,the flexible control method of robot is put forward.(2)It uses the D-H method determining the kinematic model of the ankle joint,which laies the foundation for the further research of the rehabilitation robot.Furthermore,it bulids the Matlab/Simulink model of rehabilitation robot and its DC torque motor MATLAB/Simchanics model,which is the foundation of the whole system simulation platform.(3)By comparing and analyzing the flexible control method of robot,it selects the impedance control method finally.Meanwhile,it briefly analyzes the impedance control method in two modes: based on the position and based on the force.For the control method mode which based on the position,it establishes the system simulation platform based on Simulink,and make the corresponding simulation analysis.Finally,the simulation results prove that the impedance controller design can achieve training trajectory control of the rehabilitation robot moving platform compliantly.By adjusting the parameters of the impedance,it can make the robot show different compliant characteristics.(4)For patients' different stages of recovery,it will design corresponding impedance parameters self adjusting fuzzy controller.The fuzzy controller can select the best impedance parameters according to the formulation of fuzzy rules,and can also adjust the impedance parameters online according to the change of contact stiffness,making the whole system show a better anti-interference ability and good dynamic performance.Based on MATLAB/Simulink simulation platform,the impedance control method is analyzed and verified.Finally,the result has proved its feasibility.The main purpose is to realize compliance control for ankle rehabilitation robot,avoiding the users suffer the secondary injury in the use process.