Research on Automobile Suspension Performance Evaluation System with Adjusting-Frequency Method

Suspension is a crucial assembly for automobile controlling stability and safety. For achieving the effective and precise detection the suspension system, the simulation model based on 1/4 vehicle dynamic model is constructed. The model includes linear sinusoidal frequency excitation signal, 1/4 vehicle suspension´s two degree of freedom vibration system, body acceleration, relative dynamic load, the output model of suspension´s dynamic deflection. Simulation results show that in the condition of linear sinusoidal frequency excitation, the amplitude-frequency curves of vibration response values such as the vehicle body´s acceleration, the wheel´s relative dynamic load and suspension´s dynamic deflection which obtained by simulation accords with the law of 1/4 vehicle suspension´s vibration model and theoretical analysis. Vibration response value causes resonance phenomenon and generates peak values in the vicinity of 1 Hz and 11 Hz. From amplitude-frequency curve, we can determine frequency components and frequency distribution range of vibration signals, define the amplitude and energy of every frequency components, and accordingly carry out fault diagnosis on the vehicle´s suspension system.