Research on Steering Stability Control Strategy of Four-wheel Independent Electric Drive Special Vehicles

In order to solve the steering stability problem of a special four-wheel independent electric vehicle, a dynamic model of the vehicle was established to analyze the cause of vehicle instability. A steering stability controller was designed, which included the upper yaw moment controller and the lower driving force distribution controller. Based on the sliding mode control algorithm, the yaw moment controller determines the yaw moment required while the vehicle is moving by controlling the yaw rate and sideslip angle. Based on the safety distribution method, the driving force distribution controller selects the sum of tire utilization rate as the optimization function to realize the optimal distribution of yaw moment. Software of MATLAB/Simulink and CarSim were used to build a co-simulation platform, and the designed steering stability controller was analyzed and verified. The simulation results show that the steering stability controller is helpful to improve the steering ability and handling stability of the vehicle in the extreme working conditions.