Optimal vibration control for active suspension systems with actuator and sensor delays

The problem of optimal vibration for time-delay systems is considered. The delayed system is transformed into a non delayed one by using functional transformations. The optimal control law consisting of state feedback and feedforward compensator is derived from a Riccati equation and a Sylvester equation. The feedforward control compensates for the effect of road vibration. A control memory term is designed to compensate the effect of the actuator delay. An observer is constructed to make the controller physically realizable. Simulations for the full-car suspension system illustrate the effectiveness of the proposed controller.