Research on Semi-Active Suspension Attitude Control for Commercial Vehicle Cab Under Braking and Steering Conditions

During transient maneuvers such as emergency braking and steering, the cab attitude of a commercial vehicle may change abruptly, thereby posing a potential risk to driving safety. To address this issue, this study investigates a cab attitude control method for a specific commercial vehicle under braking and steering conditions based on a semi-active suspension system. First, full-vehicle road tests were conducted under emergency braking and steering conditions. The measured signals at the lower mounting points of the cab suspension were collected, preprocessed, and used as disturbance inputs to the system. Subsequently, performance tests were carried out on a continuous damping control (CDC) damper, and forward and inverse interpolation-based lookup table models of the damper, together with a three-degree-of-freedom predictive model of the cab, were established. In addition, a model predictive control (MPC) controller for the semi-active suspension was designed based on the predictive model, with different performance indices formulated for the braking and steering conditions. Finally, the control effectiveness of the MPC method on the cab attitude responses under braking and steering conditions was evaluated using the MATLAB/Simulink platform. The results show that the proposed control method can effectively improve the dynamic responses of the cab in terms of vertical acceleration, pitch angular acceleration, and roll angular acceleration, thereby mitigating braking- and steering-induced cab attitude deviations.