Design And Analysis Of The Spatial Four-degree-of-freedom Lower Limb Rehabilitation Robot

With the increasing proportion of cerebrovascular disease,the lower limb rehabilitation robot which assists physicians in rehabilitation training has become a research hotspot.The design and research of the lower limb rehabilitation robot mechanism has important practical significance for improving the rehabilitation quality of patients,reducing the pressure on physicians and improving the training efficiency.Therefore,a multi-functional serial-parallel hybrid lower limb rehabilitation robot is proposed for patients with lower movement dysfunction.Firstly,based on the current background of many patients with lower limb functional disorders caused by various factors and based on the market requirements for the performance of lower limb rehabilitation robots,a spatial four-degree-of-freedom lower limb rehabilitation based on serial-parallel hybrid mechanism was proposed.The robot can achieve rehabilitation training for the flexion of the hip,knee,ankle and extension of the hip.By establishing a human-machine model and determining the basic parameters of the mechanism,the three-dimensional design of the lower limb rehabilitation robot was carried out.Secondly,the forward kinematics and inverse kinematics were carried out for the lower limb rehabilitation robot.The kinematics model of the human-machine system was established and the Jacobian matrix of the model was analyzed.The dynamic model of the mechanism was established.The simulation has been conducted to verify the kinematics and the Jacobian matrix by ADAMS.Thirdly,the motion path of the robot was designed and three training trajectories of linear trajectory,circular trajectory and combined trajectory were designed.In order to make the trajectory continuous and smooth,the displacement,velocity and acceleration were designed and the rationality of human joint movement were verified.The static analysis of the mechanism was carried out,and the selection of key components of the mechanism was completed based on the results of static analysis.Finally,the prototype of lower limb rehabilitation robot was developed,the hardware control system of the prototype was built,the upper computer program of the control system was programmed and the prototype was debugged.The passive training and active training control scheme were proposed.A lower limb rehabilitation evaluation standard based on analytic hierarchy process was established and a rehabilitation evaluation model was established.The local evaluation and overall rating of functional patients with lower limb were realized.Based on the built system,the trajectory tracking experiments of three trajectories were carried out,which verified the correctness and rationality of trajectory planning.