SEMI-ACTIVE SUSPENSION CONTROL IN A PASSENGER CAR USING A GA-FUZZY APPROACH

A quarter-car hydraulic semi-active suspension system is designed and built for investigating its dynamic model and control behavior. For improving the dynamic response performance, controllers that use a fuzzy logic scheme and a GA-fuzzy strategy are adopted and compared experimentally. Generally, the fuzzy logic controller (FLC) has a limitation on the best performance it can deliver. Therefore, the authors used a genetic algorithm (GA) to determine the optimal parameters of FLC. The experimental results for the vibration amplitude of the car body clearly indicate that the proposed GA-fuzzy controller can achieve good driving quality. However, the power spectral density (PSD) of the sprung mass acceleration shows that with this scheme, riding comfort is improved only restrictively. Therefore, a efficient method is proposed and simulated.