Experimental evaluation of a fuzzy logic controller on a quarter car test rig

This paper considers the experimental investigation of a multiple-input single-output fuzzy logic controller on an active suspension system based on a quarter car test rig. Prior to implementation of the controller, the quarter car test rig is described in detail. Afterward, the structure and design of the implemented fuzzy logic controller is presented. In this study, fuzzy logic control is preferred, since it does not require the exact mathematical model of the system and allows using expert knowledge about vehicle suspensions. Experimental results are presented and discussed via extensive time and frequency responses. Classical fuzzy logic controller is also utilized for comparison. Time responses of sprung mass displacements and accelerations, suspension deflections and actuator forces are compared for passive system and active controllers. Finally, the frequency responses of sprung mass displacements and accelerations are also compared. From the results it is deduced that the multiple-input single-output fuzzy logic controller performed well when compared with passive and classical fuzzy logic controlled systems.