Optimal fuzzy control of a semi-active suspension of full-vehicle model

The study focuses on a semi-active control of two steps to isolate the vibration of a full vehicle suspension with 4 MR (Magneto-Rheological) dampers installed between the vehicle bodywork and four un-sprung masses. The first step is to design 4 pairs of control forces through independently designing the LQG control and Kalman filter. And the second step is to make the 4 pairs of restoring forces of those MR dampers approach to the 4 pairs of control forces by using the fuzzy control. The numerical simulations demonstrate the better performance of the optimal fuzzy control in the semi-active vibration control of the full vehicle suspension compared with the current clipped-optimal control. For instance, the optimal fuzzy control works effectively in reduction of the vertical acceleration and the roll angular acceleration of the vehicle body, as well as the dynamic Deflection of the suspension, such that the vehicle receives better ride comfort and handling stability. The fuzzy controller is quite easy to be realized on line as the design of the fuzzy controller is independent of the optimal control law of the suspension. Furthermore, it can also be combined with other control strategies, and extended to other applications of MR dampers.