Optimization design on dynamic characteristics and fatigue life of automotive suspension system

A multi-body dynamic model of the suspension system was built in this paper. The vibration displacement of wheel center on running pavement was obtained by experiment and applied it into the multi-body dynamic model to simulate actual operation conditions. Then, vibration acceleration of suspension axle was extracted and compared with the experimental result. The dynamic load acting on the suspension jounce bumper was acquired by the multi-body dynamic model and applied to the finite element model of the jounce bumper. Then, the stress in the loading position was computed and imported into NASTRAN to conduct fatigue durability analysis of the jounce bumper. Afterwards, the dynamic characteristic and fatigue life of the jounce bumper were optimized based on the improved genetic algorithm. Finally, vibration isolation ratios of the suspension system before and after optimization were compared to verify optimization effect. In this way, the suspension system has a better dynamic characteristics and higher fatigue life.