Filter-Based Adaptive Vibration Control for Active Vehicle Suspensions With Electrohydraulic Actuators

Vehicle suspension systems are important for significantly improving passenger comfort and handling characteristics. A well-designed suspension system can improve the entire performance of the automobile chassis. In this paper, an adaptive vibration control strategy is proposed for nonlinear uncertain suspension systems to stabilize both the vertical and pitch motions of the car and, thus, to contribute to ride comfort. Simultaneously, ride holding performance is preserved within allowable limits in the controller design. Moreover, differing from the existing results, in most of which the effect of actuator dynamic is neglected, this paper considers the electrohydraulic systems as actuators to supply active forces into suspension systems. Furthermore, to overcome the "exploration of terms" problem existing in standard backstepping, a filter-based adaptive control strategy is subsequently proposed. Finally, a design example is shown to illustrate the effectiveness of the proposed active controllers, where different road conditions are considered in order to reveal the closed-loop system performance in detail.