Research on Active Steering Control Strategy of Tractor-Trailer Combination Based on Co-Simulation

In order to improve lateral stability of the tractor-trailer combination in high-speed driving, while avoiding the occurrence of swing instability. In this paper, the optimal active steering angle of the upper level control is obtained by building the model of the vehicle combination, taking the yaw rate as the reference rear amplification coefficient (RWA) and the sideslip angle of the vehicle combination as the control objective of the fitness function, using the genetic algorithm(GA) to optimize the weight of the linear quadratic controller (LQR) in Simulink and adjusting it. According to the Ackerman steering principle, the steering angle relationship between the left and right wheels is determined, and the optimal active steering angle is used for the lower level control, which is allocated to each wheel of each vehicle unit of the tractor-trailer combination. Compared with the non active steering control, the co-simulation control makes the RWA values of the vehicle combination drop by 37.25% and 40% respectively. The co-simulation shows that the active steering can improve the lateral stability of the vehicle combination, which lays the foundation for the application of the active steering control strategy of the heavy vehicles.