Coordinated Control of Longitudinal, Lateral and Vertical Motions for Active Suspension Based on Vehicle Dynamic Model

In order to realize the vertical cooperative control of active suspension considering the lateral and longitudinal motion of the vehicle and solve the uncertainty disturbance problem in the vehicle suspension system. In this paper, a 14 degree of freedom vehicle dynamics model is established, and an active suspension control strategy based on the vehicle model is proposed. The proposed active suspension control strategy can adaptively deal with the uncertain disturbance of the suspension system to improve the ride comfort of the vehicle. Firstly, the vehicle dynamics model, which includes six degrees of freedom of the body and spin and vertical motion of the wheel total 14 degrees of freedom is established. Secondly, the uncertainty disturbances that may exist in the vehicle suspension system model are fully considered, and the expanded state observer (ESO) is used to observe the uncertainty disturbances. Finally, the extended state observer and model predictive control (MPC) are combined to realize the uncertain disturbance adaptive active suspension control. Through simulation, the proposed control strategy is compared with the passive suspension, the active suspension that does not consider the horizontal vertical coordinated control and the uncertain disturbances. The simulation results show that the active suspension control strategy proposed in this paper, which considers the horizontal longitudinal vertical coordination and disturbance control of the whole vehicle, effectively reduces the acceleration, body roll angle and pitch angle of the body, and can achieve better ride comfort under the conditions of single lane change and double lane change.