Robust output fuzzy control for vehicle lateral dynamic stability improvement

This paper deals with the robust control for Four Wheels Steering (4WS) vehicle dynamics when the road adhesion conditions change and the sideslip angle is unavailable for measurement. The non-linear model of the vehicle is first represented by an uncertain Takagi-Sugeno model. Next, the robust output stabilisation of the vehicle is considered. The controller and the observer are designed in terms of Bilinear Matrix Inequalities (BMI) problem. A method is then proposed to get the LMI formulation resolved sequentially. The obtained simulation results indicate that considerable improvements in the vehicle handling can be achieved when the vehicle is governed by the proposed fuzzy observer-based controller.