The Research On Automobile Electronic Stability Program Fault Tol Erant Control Based On Constraints Of Wheel Slip Rate

The electronic stability program is developed on the basis of ABSand TCS.When solenoid valve malfunction of the wheel, it will seriouslyaffect the ESP. Analyze ESP hydraulic regulator solenoid valvemalfunction, and study the effect of fault on the vehicle dynamics. Takethe corresponding fault-tolerant control strategy, and keep the vehiclestable after the fault.The longitudinal and lateral forces of wheel is decided by slip rate,side-slip angle and wheel vertical pressure. The lateral force generated byside-slip angle is reduced with the increase of the slip rate, and this featurecan be used to control the lateral force and the yaw moment. Analyzebraking force of each wheel and look for the relationship that each wheel can provide, then classify the yaw moment according to different steeringconditions. Brake the wheel that can provide the opposite yaw momentwhen a wheel failure caused by abnormal brake in order to offset theexcessive yaw moment. Similarly, brake the wheel that can provide thesame yaw moment in order to compensate inadequate yaw moment. Thenthis method can keep the vehicle stable in the case of ESP actuator failure.In the fault-tolerant control strategy, use the longitudinal and lateral forceof the wheel as the intermediate variable, and according to the change oflongitudinal force and lateral force to find the relationship between the sliprate and yawing moment. Then we can calculate the slip ratecorresponding to certain additional yaw moment, so we can converted thecontrol of yaw moment into the control of the slip rate. Thus, we canreduced the control complexity.