Simulation and Test Study on the Nonlinear Control for Vehicle Body Height with Hydropneumatic Active Suspension

To control the body height of vehicle with hydropneumatic active suspension system, this paper presents a new control strategy to eliminate the oscillation arising from friction force and occurring in conventional PID control.According to a nonlinear suspension model,this control strategy based on variable structure control and PID control is presented and a switch method of the coefficient of the integration part of PID control is proposed.The new control strategy comkining variable structure with PID control is developed.The simulation and test results show that this control strategy can obtain better control effects on vehicle body height than conventional PID control.