Adaptive Fuzzy Control for Active Suspension Systems with Stochastic Disturbance and Full State Constraints*

In this paper, an adaptive fuzzy control scheme is proposed for one-quarter automotive active suspension system with full sate constraints and stochastic disturbance. In the considered active suspension system, to further improve the driving security and comfort, the problems of stochastic perturbation and full state constraints are considered simultaneously. In the framework of backstepping, the barrier Lyapunov function is proposed to constrain full state variables. Consequently, by combing the Itô differential formula and stochastic control theory, an adaptive controller is designed to adopt the uneven pavement surface. Ultimately, on the basis of Lyapunov stability theory, it proves that the designed controller not only can constrain the bodywork, the displacement of tires, the current of the electromagnetic actuator, the speeds of the car body and the tires within boundaries, but also can eliminate the stochastic disturbance.