Simulation Study of Automobile ABS/EBD System
|School||Shandong University of Technology|
|Keywords||ABS/EBD system control strategy joint simulation slip ratio ADAMS/Car|
With the rapid development of automobile technology, the speed of automobile is higher and higher, the number of traffic accident becomes more and more, the braking performance directly affect the active safety of vehicle. ABS/EBD system can improve the braking performance and the active safety of vehicle. When the vehicle is braking, antilock braking system (ABS) can protect the wheels from locking, it can improve the direction stability and steering control capability of the car. Electronic brake force distribution (EBD) is developed on the basis of ABS system, it can auto adjust the braking force distribution among the wheels before ABS system start to work. EBD system makes the rear wheels to track front wheels. At the present, the research on the ABS system mainly use logic gate control method based on slip ratio and angular deceleration in our country, the study of EBD system is on the initial stage. In order to further study the control strategy of ABS/EBD system, this paper uses the slip ratios of front and rear wheels as the target control and respectively study ABS system and EBD system, the study includes the following sections:(1) According to vehicle motion parameters and Newtonian mechanics, the vehicle model is established in MATLAB/Simulink, besides, vehicle hydraulic braking system is studied and hydraulics and tyre models are established.(2) The control strategy and method of ABS system and EBD system are studied, ABS controller uses sliding mode control method and stateflow control method, while, EBD controller makes use of fuzzy control method and PID control method.(3) ABS system、EBD system and ABS/EBD system controllers are established in MATLAB/Simulink, after that, the controllers are simulated on different road conditions in MATLAB/Simulink.(4) Based on virtual prototype technology, a model which is more close to the real vehicle was established by using ADAMS/Car software; it can reflect the dynamic characteristics of vehicle more truly. ADAMS/Car software and MATLAB/Simulink software are united to simulate the performance of the designed control system. Through the comparision of the simulation curve, it shows the controllers builded in MATLAB/Simulink are right.Through the simulation study of ABS/EBD system, the results show that the control strategy of ABS system、EBD system and ABS/EBD system are right, they can able to meet the vehicle’s demand when the vehicle is braking.