Research On Lateral Control Of Vehicle With Tire Blow-out

The vehicle tire blow-out will lead to the occurrence of many serious traffic accidents. If a tire blow-out happens, the parameters of the tire will change greatly,which has a negative effect on the vehicle stability. This paper presents a lateral control method for the vehicle with a tire blow-out.First of all, the tire parameters of vehicle with tire blow-out were analyzed to determine the effect of tire parameters- cornering stiffness, vertical stiffness, and rolling resistance coefficient. The simulation based on high precision nonlinear vehicle dynamics software ve DYNA simulation is be used to determine the main effects on the vehicle dynamic when tire blow-out happens. Then select the vehicle lateral velocity,yaw angular velocity, yaw angle and lateral displacement as the state variables to establish the vehicle lateral dynamics model.According to the vehicle dynamics in the process of the actual situation, the system state constraints and control input constraints are determined.Then, according to the characteristics of the system,a constrained H-infinity state feedback controller based on differential braking has been chosen. According to the Hinfinity controller design theory, determine the matrix inequality needs to meet, and get the state feedback gain matrix through the LMI toolbox of MATLAB.Then, the distribution of braking torque is determined by analyzing the brake yaw moment. To make the vehicle with a tire blow-out can quickly stop, the rear wheel brake has been added to the control strategy, and the effect of the rear wheel brake is simulated and compared. At the same time, the ability of the controller to suppress the driver’s steering disturbance is simulated.Then the tire controller in the intervening time and control effect are analyzed, and the different controller intervention delay control effect is simulated and compared.Finally, the research on hydraulic control and vacuum assisted braking system-the important part in the control of burst control. Of the hydraulic system, analyzed the active pressurization characteristics and decompression characteristics, and the effect of braking general pump to the hydraulic circuits were considered, the feedforward and PI switching hydraulic controller is designed. Then, according to the brake wheel cylinder pressure and decompression characteristics, the wheel cylinder hydraulic control strategy has been designed. Then, through the hardware in the loop test, in the actual hydraulic system verify the performance of the controller. Of vacuum system, on the real vehicle for the vacuum pump and pumping characteristics of gas and vacuum system natural leakage characteristics were tested. Through the analysis of the identified under different working conditions of the vacuum pump activation threshold andthreshold closure. At the same time, because of the electric vehicle vacuum assisted braking system has more fault point, the vacuum power fault detection procedure has been designed.On the basis of the above, give out the final complete structure of lateral differential braking controller for vehicle with tire blow-out.