Structure optimization and finite element analysis of the human body exoskeletons lower limb power

Abstract

The lower limbs is carrying subject mechanical structure for the human body exoskeletons, and the hydraulic cylinder provides motivation; Three hinge point to the knee joint structure is the best layout and mechanical structure bearing performance as the research target; According to the human body bone and joint constitute, human exoskeletons lower limb power structure 3 d model is established and the function relationship between the hydraulic cylinder bearing capacity and the weight is established. The hydraulic cylinder bearing capacity is taken as optimal objective function components for outside bone size constraint conditions; Through the self-adapting inertia update and update the simulated annealing particle position particle swarm algorithm by analyzing and solving the three hinge point exoskeletons that the structure of the optimal solution; Entities modeling is erected through the ANSYS software and one knee two typical motion is taken for working attitude. Finite element analysis of strength is taken for foreign bone lower limb power structure. Structure and finite element analysis results show that the simulated annealing particle swarm algorithm in the iteration to 150 generations when convergence to optimal solution, and this operation finds the optimal solution, the algorithm and reliable; Exoskeletons upright maximum stress is produced in the knee, for 128 MPa, closed to the allowable stress value, structural design is reasonable; The hydraulic cylinder maximum stress for 5.76 Mpa, far less than the allowable stress value, hydraulic cylinder force minimum, achieve the objective function optimization indexes; To one knee, the greatest stress produced in the right leg knee, the greatest stress for 252 MPa, greater than the allowable stress value, and puts forward the measures to strengthen local knee structures. © 2012 Springer-Verlag.