Study On Robust Control Of An Automobile Active Suspension Based On T-S Fuzzy Model

The suspension is one of important automotive assembly, which has prodigious influence on performance of ride quality and handing stability. So it is crucial to design excellent suspension system for automotive quality. Passive suspension is difficult to met requirements for a car which pursuit under levity perplexing environments. The active suspension is development direction and has become a kinetic research topic of automotive field in the world. Automotive suspension is a nonlinear system, as for nonlinear systems, it is difficult to get the accurate mathematic model. Even we can build mathematic model for those systems, it may be too complicated to design a controller with conventional means.A half-automotive 4 degrees of freedom active suspension T-S fuzzy model is established in this paper and study on the T-S fuzzy model of an automotive active suspension system:A suspension fuzzy H_∞controller based on the model is proposed. Considering some states can not be measured, the state observer is designed and the fuzzy control law is obtained by solving the linear matrix inequalities (LMIs). The closed-loop fuzzy system achieves global asymptotic stability by the fuzzy controller presented, and H_∞control performance is also gained. Thesimulation shows that the system can achieve stability fast, the ride performance and safety of automotive are effectively improved.An optimal fuzzy guaranteed cost controller is proposed based on the model. A satisfied result is got for controlling suspension system with parametric uncertainties. The result shows that the active suspension is superior to the passive suspension in reducing vibrate and improving the ride comfort.