Coordination control of semi-active suspension and multi-motor torque distribution for anti-roll and anti-pitch performance

Abstract

A new roll angle state observer is proposed based on a 7-degree-of-freedom (7-DOF) suspension model to estimate the vehicle’s roll angle and roll rate. Using the estimated roll angle, the 7-DOF model and H-infinity controller predict roll angle changes, enabling the rollover warning function through integration with the lateral load transfer rate (LTR). Additionally, the semi-active suspension system, which incorporates the effect of controllable damping force on wheel vertical force, is integrated with the distributed drive system through wheel vertical force as a mediating factor. For high-speed cornering and straight-line sharp acceleration/deceleration scenarios, differential simplifications are applied to the suspension model and drive motor, accompanied by distinct H-infinity control and torque distribution strategies. The method is validated through co-simulations using Carsim and Matlab/Simulink, as well as hardware-in-the-loop experiments (HIL). The experiment results indicate that, in comparison with the passive suspension system, the proposed cooperative control method significantly enhances the vehicle’s ride comfort, handling stability, and driving safety.