The Influence Of Engine Torque Management On Handling Stability Of Vehicle

ESP(Electronic Stability Program),through online vehicle sensor system,in real-time,monitors the intent of driver and driving condition,identifies and assesses the vehicle steering character and the trend of control-losing,through engine torque and wheels brake control and prevents vehicle from understeering and oversteering. ESP enables vehicle to realize driver`s steering intent and at the same time,improves its stability and direction performance.Since ESP was installed as vehicle initiative safety device,it has prevented a large number of traffic accidents,and has created significant social and economic benefits.At present,ESP,ABS(Anti-lock Braking System)and TCS(Traction Control System)have been integrated into a new generation of ESP,whose key technology and market have been mastered in Europe,North America,Japan,and other countries enjoying more developed auto industry.However,in China,both the ESP assembly rate and the research on ESP technological development are in the initial stages.In this paper,basis of foreign car ESP technology research experience,the content and implementation of research are settled,and according to"The influence of engine torque management on handling stability of vehicle",the main contents are described as below:At first,the paper builds a fifteen degree of freedom vehicle model based on the AMESim software. Vehicle model comprise several key parts of vehicle,such as engine,transmission,tire and whole vehicle and etc. We verified the optimization theory can be used in ESP to improve the stability of the car by the vehicle model.Secondly, ESP control mostly includes two aspects content--research of ESP brake control and engine management.ESP brake control could solve most situation and ESP engine control can make stability better sometimes,so engine management is an important part of ESP.The key point of this paper is the influence of engine torque management on vehicle of handling stability control.According to the ESP system requiring the realization of the driver`s desirable track and the maintaince of the stability of driving control, the vehicle side slip angle and the yaw rate are the control variables to be considered in the paper.The ESP minimizes the difference between the actual side slip angle,yaw rate and the normal side slip angel,normal yaw rate to make sure the good maneuverability .The engine torque management control rising or decline of output torque of engine to make the vehicle in good maneuverability and good slide rate. We simulated the system at MATLAB/Simulink and AMESim software in co-simulation environment.At last, from the simulation,we found the ESP system designed with optimization theory can guarantee the manoeuvrability.It can make the car running safely in a high speed or low friction and make the driver drive the car normally. The results shows that, according to control of brake of wheels,the stability of car could get better.Also,the results shows that joint engine management and brake of ESP could make yaw rate better. So ESP with engine management could get better handling stability in some special time.