Abstract: Based on the whole vehicle’s design parameters and suspension design theories, the McPherson front suspension of an electric vehicle is designed. Based on UG/Motion and using the open interface of UG, a software system is developed to realize the parametric design of the McPherson suspension’s kinematics simulation models, matching design of vehicle toe-in and camber and simulation analysis of the simulation models. The software system’s correctness is verified by comparing the simulation results with ADAMS. By means of combining genetic algorithm with kinematics of multi-body system and taking the minimum variation of the front wheel alignment parameters as well as minimum lateral displacement of the tires as the optimal object, the McPherson suspension’s design parameters are optimized. The validity of the optimum method is verified by comparing the simulation results of initial design and optimum design. The optimization results show that the coordinates of the McPherson suspension swing arm’s front and rear points have effects on the changes curve of front wheel alignment parameters as well as lateral displacement of the tires to the run out of automotive wheels.

Key words: Electric vehicle, Genetic algorithm optimization, Kinematics analysis, McPherson suspension