Research On Configuration Of Knee Joint Rehabilitation Robot Based On Cable Transmission

In knee rehabilitation,rehabilitation training is one of the important treatment strategies.It has the functions of improving joint mobility,preventing joint adhesion,enhancing muscle strength and forming nerve synapses.The rehabilitation effect is completely dependent on the clinical experience and technical level of the rehabilitation therapist by using traditional rehabilitation training methods.The inadequate clinical experience and low technical level of the rehabilitation therapist lead to low rehabilitation efficiency and easily cause secondary knee injury,which is not good for the functional restoration of the knee joint.The robot assists rehabilitation therapist to complete knee joint rehabilitation training,reduce the work intensity of rehabilitation therapist,improve the efficiency of rehabilitation training,and enhance the effect of knee joint rehabilitation.This thesis takes the configuration of knee joint rehabilitation robot as the research object.The research content includes the research on the movement mechanism of knee joint and the establishment of its physical model;the research on the three-degree-of-freedom motion law of knee joint in sagittal plane,and the coupling relationship of motion law among three degrees of freedom;the structural innovation of knee rehabilitation robot;the kinematics analysis and kinematics simulation of knee rehabilitation robot;the research on prototype experiment of knee rehabilitation robot.The main work and research content are as follows.(1)Research on the movement mechanism of the knee joint.According to the physiological structure of the knee joint and the cooperation mechanism of various tissues in the process of knee joint movement,the physical model of the knee joint is constructed by referring to the knee joint motion model(the variable axis rotating pair with the rotating axis perpendicular to the sagittal plane but the instantaneous center changed continuously).It provides a theoretical basis for the structural design of knee rehabilitation robots.(2)Research on the motion law of knee joint.According to the knee joint movement mechanism,the knee joint gait parameters and kicking motion parameters are measured by using the time-varying coordinate method.On the one hand,it is determined that the main motion of the knee joint is the flexion and extension of the sagittal plane;On the other hand,the motion law of each degree of freedom of the tibia relative to the femur in the sagittal plane was measured,and with the help of MATLAB curve fitting function,the coupling relationship of motion law between each degree of freedom was analyzed.It provides a data support for the structure design of knee joint rehabilitation robot.(3)Structural design of knee joint rehabilitation robot.According to the physical model of the knee joint and the coupling relationship of motion law between the each degree of freedom of the knee joint,the overall configuration of the knee joint rehabilitation robot is constructed by using the double-fork bar structure as the design core and constructing the cable transmission system.It ensures the structural strength of the knee joint rehabilitation robot by using ANSYS software to check the strength of key components,selecting important component models and checking the related parameters of the important component.(4)Kinematics analysis and kinematics simulation of knee joint rehabilitation robot.Based on the screw theory,the kinematics analysis of the knee joint rehabilitation robot is completed.The forward kinematics equation was derived,and the inverse kinematics inverse solution was solved.Based on virtual prototype technology,the kinematics simulation of knee joint rehabilitation robot is realized with the help of ADAMS software.Compared with theoretical values,the simulation results prove the rationality of the structure of the knee joint rehabilitation robot theoretically.(5)Research on prototype experiment of knee joint rehabilitation robot.The prototype of knee rehabilitation robot was built,the experimental platform was built,and the knee rehabilitation robot was driven to achieve knee extension.By using time-varying coordinate method and MATLAB software,the motion law of knee rehabilitation robot is analyzed.According to the theoretical curve and fitting curve,the feasibility of the structure of knee rehabilitation robot is verified.The innovation of the work is reflected in the construction of a new physical model of the knee joint by referring to the new knee joint motion model.The time-varying coordinate method was used to measure the motion law of each degree of freedom of the knee joint in the kicking movement,and the curve fitting theory was used to analyze the coupling relationship of motion law between each degree of freedom of the knee joint.A physical model of the knee rehabilitation robot is built by using the double-fork bar structure according to the coupling relationship of motion law between each degree of freedom of the knee joint,so as to realize the motion law of the knee in each degree of freedom.