Modeling And Analysis Of Human Lower Limb Bionic Testing System Based On Six-axis Linkage

At present,the development of medical aids for lower extremity rehabilitation is in full swing,and patients can effectively improve their lost motor functions through treatment and training with rehabilitation aids.In this paper,by establishing a biomechanical bionic test device that simulates human motion function,through the developed human knee joint prosthesis simulation motion and mechanical testing function,various dynamic data of human hip,knee and other joints under different flexion angles are measured.,describe the motion curve of human lower limbs under different forces and functional actions;measure the force of human knee joint prosthesis,and optimize surgery,prosthesis and rehabilitation treatment.Therefore,it is of great significance and application value to design a flexion motion device that can perform bionic simulation of human lower limbs.The main research contents of this paper are as follows:First,the dynamics and kinematics of the human lower limb flexion motion model are analyzed.The Lagrangian method is used to analyze the dynamics of the lower limb flexion movement,and the dynamic equation is obtained through mathematical operations,and the dynamic analysis of the lower limb flexion movement is completed.The movement is analyzed by forward kinematics and inverse kinematics;it lays a theoretical foundation for the next study on the control problem of the bionic flexion motion device of human lower limbs.Secondly,the PID closed-loop control method is introduced into the drive control of the motor,and further combined with the fuzzy concept,the basic model of the fuzzy PID control of the stepping motor is established,and the simulation is carried out by using the Simulink module in MATLAB to verify the feasibility of the fuzzy PID control.The control algorithm foundation is laid for realizing precise control of the motor and fast driving of various muscle movements.Then,the mechanical structure and control system of the buckling device were designed,and the control program was developed with the Arduino microcontroller as the lower computer,which converted the movement of the muscle bundle with the pulse number of the stepping motor,and combined the fuzzy PID control algorithm to complete the experimental device’s construction.Finally,the construction and debugging of the experimental prototype and the writing of the control algorithm are completed,and the motion test and experimental verification of the device are carried out.The experimental results show that the bionic flexion device can complete the complete flexion movement and can perform the flexion movement according to the predetermined tension value,and obtain the relevant data of the contact pressure of the patella of the knee joint and the contact pressure of the meniscus.