Research on random vibration control of vehicle based on semi-active suspension system

In this paper, a new research for semi-active suspension system of vehicle is proposed. Assuming the stochastic excitations are Gauss white noises, we establish a stochastic model on semi-active suspension system. Here we consider two kinds of stochastic excitations: one is the inner multiplicative excitation brought by the inner system such as the spring and damper, the other is the outer excitation brought by outs-side world. The model we defined is considered as a weak damp and weak excitation quasi Hamiltonian system. The max Lyapunov exponent was calculated by quasi non-integrable Hamiltonian theory and Oseledec multiplicative ergodic theory, the local stability conditions had been obtained; the global stability conditions had also been obtained by judging the modality of the singular boundary; the stochastic Hopf bifurcation was analyzed from the sharp change of stable probability density, and the condition of stochastic Hopf bifurcation had been discussed.