Yaw stability control through independent driving torque control of mid and rear wheels of an articulated bus

Abstract

This paper describes a novel yaw stability control strategy for a four-wheel-independent-drive electric articulated bus with four motors at the middle and rear wheels. The proposed control strategy uses a hierarchical control architecture. In the upper layer, a 3 degree-of-freedom reference model is established to obtain the desired vehicle states and the desired yaw moments of the front and rear compartments are determined by means of sliding mode control, respectively. The lower layer distributes differential longitudinal forces according to the desired yaw moments based on quadratic programming theory. The tire utilization rate is used as the optimization goal considering the actual constraints. To verify performance, three test cases are designed on the dSPACE-ASM simulation platform. The test results show the proposed control strategy can improve the yaw stability and the trajectory following performance of the bus under different driving conditions.