Comparison of H-8 and Optimized-LQR Controller in Active Suspension System

The objectives of this paper are to establish the mathematical model and the robust control technique of the active suspension system for a quarter-car model. The aim of a car suspension system is to improve riding quality while handling characteristics subject remain good to uneven or rude road surface. The purpose of designing the controller for the car suspension system is to reduce the traditional design as trade-off between ride comfort and handling by directly controlling the suspension force to road and driving conditions. The H-∞ and LQR controllers are used to reject the effects of road disturbances. H-∞ controller is able to reject the uncertainty of the system and remain the system robustness while road disturbance enter to suspension system. The controller and suspension system performances are simulated to proof the effectiveness of the proposed controllers. Simulink Response Optimization toolbox in matlab is used to optimize the best gain for the controller feedback. The performance of the H-∞ controller is compared with the LQR controller, LQR optimize and the passive suspension systems.