Semi-active fuzzy sliding mode control of full vehicle and suspensions

The suspension of a vehicle is the support system between a vehicle body and wheels. The purpose of a suspension system is to support the vehicle body and increase ride comfort. Care must be taken in the design of a suspension system because if the attenuation force becomes large, the passenger will be subjected to a very rough ride under high-frequency disturbances, and if the attenuation force becomes small, the ride will feel overly soft at low frequencies. Furthermore, if the spring constant is too low, the vehicle's natural frequency of vibration will be low, and thus the heave, rolling, and pitching will be large. In this study, a fuzzy sliding mode controller for a real vehicle has been designed. A new method for designing the fuzzy sliding mode switch hyperplane has been proposed. Experiment results are presented to confirm the effectiveness of this new algorithm.