A tunable fuzzy logic controller for vehicle-active suspension systems

A novel fuzzy-logic-based control for vehicle-active suspension is suggested. The vehicle vibration and disturbance are reduced considerably with a fuzzy logic controller, to enhance comfort in riding faced with uncertain road terrains. A quarter-car active suspension system is controlled to reduce the vertical acceleration to a level of, that of, a hypothetical reference model. A new look-up table for the rule base of the fuzzy logic controller has been developed. The parameters, like, the spread, flex and centre of the bell-shaped membership functions associated with the different linguistic variables are fine tuned by trial and error method to get the suspension acceleration and deflection on par with that of the model. Simulation studies clearly demonstrate the effectiveness of the fuzzy logic controller for active suspension systems. The performance of the fuzzy logic controller under variations in the suspension component characteristics are also studied and was found to give reasonably good responses.