Research on vehicle handling stability of variable steering ratio four-wheel-steer-by-wire system

According to the vehicle lateral motion dynamics model,the complete feedback control strategy is adopted.Considering the difference between people,the combination coefficients influencing control strategy are proposed,and the steering ratio and the steering gain are adjusted after the combination coefficients are chosen by people.Simulation results show that the side slip angle can reduce to zero,the lateral acceleration gain and yaw angle velocity gain can keep invariant,and the system fluctuation amplitude and the time entering into the steady state are also reduced.While maintaining the above-mentioned characteristics of the same circumstances,the choice may be user-friendly steering gear ratio and steering gain,in order to further enhance the vehicle′ s handling and stability,driving safety and driving comfort.