Research On Structural Design And Gait Planning Of Lower Limb Exoskeleton Robot

With the progress of science and technology,the application of human computer interaction,assisted medical treatment and robotics are increasing in daily services area,bringing many conveniences to people's life.The purpose of article is to assist the elderly to walk on foot and reduce expenditure of energy,the design research of the lower extremity assisted exoskeleton robot with the design goals of simple structure and flexibility,system stability and wearing comfort.The main research contents are as follows:By analyzing the lower limb structure characteristics,movement mechanism and walking gait,the mechanical structure of the exoskeleton was bionic designed,the overall size of the exoskeleton was determined,the exoskeleton configuration scheme was designed,and the selection of the driving joint configuration and driving method was completed;virtual prototype of an exoskeleton was built using Solidworks,and a finite element static analysis was performed using the single leg support phase and the legs support phase in the transition period with Workbench software.The simulation results show that the robot's maximum stress is lower than the material,the allowable stress and the maximum deformation meet the design requirements.Based on the D-H parameter method and the closed solution algebra method,the forward and inverse kinematics analysis of the exoskeleton robot was performed to obtain the kinematic characteristics of the active joints;the Lagrange dynamics method was used for dynamic analysis,and the exoskeleton robot dynamic equation was established;According to the objects suitable for exoskeleton power assisted robots,fit the gait data curve suitable for the wearer,and establish an ADAMS based exoskeleton model and perform kinematic simulation to obtain the lower limb ankle,hip and knee trajectory curves,and exoskeleton walking the displacement and step curves were analyzed by analyzing the walking gait characteristics of the exoskeleton robot to verify the rationality of the structural design and gait parameters.Gait planning method based on ZMP stability criterion,the polynomial interpolation method is used to parameterize the movement curves of the exoskeleton ankle and hip joints,and then use genetic algorithm to optimize gait parameters,finally,solves the trajectory of hip joint and ankle joint;With the help of Matlab software,established motion trajectory model and the feasibility,and verified correctness of gait planning by analyzing the angular displacement and angular velocity change trajectory of the model.