This article proposes an integrated sliding mode control–two-point wheelbase preview strategy for semi-active air suspension system with gas-filled adjustable shock absorber. First of all, a vehicle suspension model with rolling lobe air spring and gas-filled adjustable shock absorber is built, following with a road input model for the front wheel. By describing the detailed structure and working process of the gas-filled adjustable shock absorber, the regulating mechanism between the stepper motor and the designed gas-filled adjustable shock absorber is established. Subsequently, the sliding mode control algorithm is applied to generate the desired damping force with the real-time state of the vehicle. Moreover, to predetermine the road profile for the rear wheel, a two-point wheelbase preview approach is proposed and its superiority is also illustrated as compared with the conventional single-point wheelbase preview approach. To evaluate the performance of the proposed system, numerical analysis is conducted with other three comparative schemes, namely, passive suspension system, active suspension system with H infinity control, and sliding mode control–controlled semi-active air suspension system with adjustable shock absorber. Simulation results show that the integrated sliding mode control–two-point wheelbase preview strategy can be successfully utilized in the semi-active air suspension system with stepper motor-driven gas-filled adjustable shock absorber, and the vehicle performance with the proposed system can be greatly improved.
Effect of Design Parameter of Hydraulic Shock Absorber of Heavy Truck Air Suspension System on Road Surface Friendliness
