RIDE COMFORT ENHANCEMENT OF MR-DAMPED VEHICLE SUSPENSION SYSTEM BASED ON FRACTIONAL ORDER FUZZY PI plus D CONTROLLER

In this paper, a fractional order fuzzy proportional-integral plus differential (FOFPI+D) controller is presented for nonlinear vehicle semi-active suspension system (SAS). The control goal is to meliorate the ride quality level by minimizing the root mean square of vehicle body vertical acceleration (RMSVBVA) and maintaining suspension travel. The FOFPI+D controller is realized using non-integer differentiator operator in fuzzy proportional integral (FPI) controller plus the derivative (D) action with additional fractional differentiator. A dynamical model of four degrees of freedom vehicle suspension system incorporating magnetorheological dampers (MRD's) is derived and simulated using Matlab/Simulink software.' The performance of the semi active suspension system using FOFPI+D controller is compared to MR-passive suspension system. The simulation results prove that semi-active suspension system controlled using FOFPI+D outperform and offer better comfort ride under road profiles such as random and bump.