Abstract: A robust steering system and suspension model are built.In the model some coordinated movements between vehicle steering system and suspension system are considered.The length of steering trapezoid arm,the angle of trapezoid mechanism,inclination angle,caster,camber and toe are defined as controllable variables,while the using conditions of load,driving force and steering torque are defined as noise factors.The optimization objectives are the minimum wheel movement deviation in some running condition.The robust optimized model is solved based on the response surface method and the robustness is analyzed based on the Monte Carlo method.Results are shown that the variances of objective functions are decreased in the robust optimization method than those results in the genetic optimization method and the robustness wheel tracks under different working condition are improved.

Key words: steering system, suspension, robust design, optimization