Structure Design And Gait Planning Of Lower Limbs Powered Exoskeleton Robot

With the advancement of science and technology,the application of human-computer interaction,assisted medical technology and robot technology in daily service field is increasing,which brings convenience for people's life.This article focuses on the above areas,and carries out research on the design of the lower limbs powered exoskeleton robot,based on the practical significance of assisting people in long-distance walking movements and reducing their physical energy consumption,as well as the design goals of simple and flexible structure,high system stability,and comfortable wear.Firstly,starting with the analysis of the structure of the lower limbs,the article designs the overall mechanical structure of the lower limb exoskeleton on the premise of following the parameters of the body structure and size,according to the module division mode of the ankle joint,the knee joint,the hip joint and the waist.In order to achieve the purpose of compact structure and system stability,the hydraulic drive scheme is selected,and the genetic algorithm is used to optimize the design of the hydraulic cylinder and the cylinder balance mechanism,and the hydraulic cylinder parameters are selected according to the optimization results.Secondly,the finite element analysis of the flexible parts of the ankle and waist is carried out by Workbench software.The simulation result shows that the maximum stress of the flexible element in the ankle joint and the waist is lower than the allowable stress of the material.And it also shows that the maximum shape variables conformed to the design requirements.Then,the D-H model of exoskeleton is established to solve the positive kinematics and inverse kinematics,and the Lagrange dynamics method is used to establish and analyze the dynamic equation.Finally,the gait of the exoskeleton is solved and analyzed using the cubic polynomial interpolation method,and the gait of the lower limb skeleton is modeled and planned with Matlab software.By analyzing the angular displacement.angular velocity,angular acceleration and terminal trajectory during the movement of the model,the feasibility and correctness of the gait planning are verified,and it is concluded that the designed exoskeleton has good wearing comfort and high practicality.The main features of the lower limbs powered exoskeleton designed in this article include:the joint structure is flexible design,which fits the body structure when wearing,and has the advantages of high comfort;the driving structure of the hip joint and knee joint adopts the humanoid balancing mechanism of hydraulic cylinder and cylinder,which has the advantages of large driving torque and stable operation;the planning and design based on the human body's actual walking posture has advantages of high anthropomorphism.