Abstract: Aiming at the adverse effects of in-wheel-motor on the design of front suspension structure and vehicle handling stability, the design of front suspension structure and parameters optimization are carried out. Firstly a steering knuckle structure suitable for the front suspension of in-wheel-motor drive vehicle is designed within available space and the coordinates of key hard-points are preliminarily determined. Then with steering handiness as optimization objective and steering returnability as constraint, an optimization model for wheel alignment parameters is established and a parameter optimization is conducted on the hard-points coordinates of steering knuckle by using integrated platform of Isight and Adams/Car. Finally both numerical simulation and real vehicle test are performed on steering handiness and returnability. The results show that after optimization the overall steering performances of vehicle are obviously improved

Key words: electric vehicles, parameters optimization, in-wheel-motor, steering performance, wheel alignment parameters