Potential of low bandwidth active suspension control with continuously variable damper

In this paper, the performance potential of a new hardware combination for active suspension systems is presented. It consists of a low bandwidth actuator and a continuously variable damper, a setup that is shown to be competitive to high bandwidth active suspension systems especially if energy, cost and implementability aspects are taken into account. This is achieved by an iterative optimization procedure for the damping ratio and the weights of time-invariant LQR controllers for active quarter-car models. The results of the procedure are obtained by simulations employing a road disturbance model that is validated using measurements of a real highway profile. The achievable performance of the new hardware combination is compared to passive and high bandwidth active suspension systems by means of carpet plots. Based on the comparison results, it is shown that ride comfort can be significantly increased while satisfying given constraints for ride safety (maximum tire deflections) and suspension travel.