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

Abstract

Vehicle suspension systems are important for significantly improving passenger comfort and handling characteristics. A well-designed suspension system can promote the whole performances of automobile chassis. In this paper, an adaptive vibration control strategy is proposed for the nonlinear uncertain suspension systems to stabilize both the vertical and pitch motions of the car, and thus to contribute to the ride comfort. Simultaneously, the ride holding performances are preserved within their 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 the active forces into suspension systems. Furthermore, to overcome the "exploration of terms" problem existing in standard backstepping, a filterbased 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.Index Terms-Active control, adaptive control, backstepping control, vehicle suspension system. 0018-9545 (c) 2015 IEEE. Personal use is permitted, but republication/redistribution requires IEEE permission. See http://www.ieee.org/publications_standards/publications/rights/index.html for more information.This article has been accepted for publication in a future issue of this journal, but has not been fully edited. Content may change prior to final publication. Citation information: DOI 10.1109/TVT.2015.2437455, IEEE Transactions on Vehicular Technology 2 0018-9545 (c)

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