Research On Vehicle Stability Control Based On Optimal Distribution Of Tire Force

When the vehicle steers at high speed or steers on a low adhesion coefficient road,it is easy to lose the stability due to the lateral force reaching the limit of adhesion.As a new vehicle active safety control technology,vehicle stability control system can effectively improve the lateral stability of the vehicle and prevent traffic accidents.In this paper,the research status of vehicle stability control system at home and abroad is analyzed,and the vehicle stability control strategy based on tire force optimization allocation is proposed.The stability control strategy proposed in this paper adopts the hierarchical structure control method.The upper yaw moment controller outputs the corrected yaw moment maintaining the stability of the vehicle in order to track the desired yaw rate;The lower control distributor is designed to optimally distribute the tire braking force to achieve the upper correction yawing moment.Among them,the upper controller is designed by sliding mode variable structure control theory,mainly solve the nonlinear problem of the vehicle system and the uncertain interference and noise in the control process.The lower control distributor is based on the optimal control allocation method,mainly solves the nonlinear problem of tire force and the redundancy problem of the optimal allocation of multiple tire force.Using Matlab/Simulink and Carsim co-simulation platform to verify the control effect of the stability control system,and compared with the rule-based single wheel and one-sided brake control method.The results show that the vehicle stability control strategy based on tire force optimization can effectively improve the lateral stability of the vehicle under complex operation conditions.Compared with single wheel and one-sided braking control method,the optimal allocation control can exert greater control potential through the combined action of multiple wheels,especially on low adhesion pavement;However,because the control algorithm of optimal allocation control is more complex,so the response speed of optimal allocation control is slower than single wheel and one-sided brake control method when the vehicle is driving on high adhesion pavement.