Finite frequency fuzzy H∞ control for uncertain active suspension systems with sensor failure

This paper investigates the problem of finite frequency fuzzy H∞ control for uncertain active vehicle suspension systems, in which sensor failure is taken into account. Takagi-Sugeno (T-S) fuzzy model is established for considered suspension systems. In order to describe the sensor fault effectively, a corresponding model is introduced. A vital performance index, H∞ performance, is utilized to measure the drive comfort. In the framework of Kalman-Yakubovich-Popov theory, the H∞ norm from external perturbation to controlled output is optimized effectively in the frequency domain of 4Hz-8Hz to enhance ride comfort level. Meanwhile, three suspension constrained requirements, i.e., ride comfort level, manipulation stability, suspension deflection are also guaranteed. Furthermore, sufficient conditions are developed to design a fuzzy controller to guarantee the desired performance of active suspension systems. Finally, the proposed control scheme is applied to a quarter-vehicle active suspension, and simulation results are given to illustrate the effectiveness of the proposed approach.