Optimal Vibration Control For Vehicle Active Suspension Systems

Driving comfort and handling stability are the main performance requirements of vehicle suspension systems,while the requirements of driving comfort and handling stability to the suspension are contradictory.In this paper,based on presentation of the models for active suspension system and road roughness disturbance,the optimal vibration control problem for vehicle active suspension systems is researched.This study is summarized as follows:1.The basic structure of automotive suspension and the impacts of the automobile suspension for the car driving comfort and handling stability were analyzed,the mathematical model of linear and nonlinear two-degree-freedom quarter-car suspension system and the mathematical model of the impacts of the road roughness disturbance on the suspension system vibration were set up2.The problem of optimal vibration control for vehicle active suspension systems under road roughness disturbance is considered.Firstly,the optimal feedforward and feedback vibration control law for vehicle active suspension systems is designed and the existence and uniqueness of the optimal control law is proved.A full state observer is constructed to make the feedforward compensator physically realizable.Numerical simulations illustrate the effectiveness of the optimal control law.3.The problem of optimal vibration control for vehicle active suspension systems under road roughness disturbance is considered.Firstly,based on the theory of successive approximation approach(SAA),the nonlinear optimal control law is designed.Numerical simulations illustrate that,the nonlinear suspension optimal control law is more effective than the linear suspension optimal control law.4.The major work of this thesis was summarized,and the direction of future research was pointed out.