Improvement of Bus Ride Comfort via Active Suspension and Connected Dampers

The paper deals with a theoretical study to present a new sort of the buses suspension systems employs a hydraulic connection between the front and rear dampers together with active suspension actuator at the front axle. The theoretical investigation based on a half vehicle model of the bus suspension system includes the engine mounting system. The hydraulic connection between the front and rear dampers is created according to the capillary tubes theory. Furthermore, the active suspension system control algorithm based on the optimal control theory is derived. The Genetic Algorithm optimization routine is applied to generate the active suspension control algorithm parameters. A comparison between the connected dampers suspension system, active suspension system, active-connected dampers suspension system, and the passive suspension system in terms of ride comfort and road holding at constant suspension working space is performed. The results showed that, the proposed active-connected dampers suspension system and active suspension system provides significant improvements in both ride comfort and road holding. Furthermore, the connected dampers suspension system has a preview control effect on the rear ride quality.