Development Of Vehicle ESP Hardware-In-the-Loop Simulation Test Bench Based On XPC Target

Vehicle Electronic Stability Program (ESP) is a new active security control system, which is developed based on vehicle Anti-lock Brake System (ABS) and Traction Control System (TCS). It has the function of generating interventions to vehicle engine and brake system actively by observing the driver's intention, the road information and the estate of vehicle, to help controlling the vehicle. Especially in the limited conditions, ESP will prevent vehicle from dangerous situation. This can enhance the vehicle handling stability and driving safety more effectively and distinctly.The process of development of ESP product is complex and long-term work. It contains the compiler of the control algorithm, the design of software and hardware, the product test and so on. In all of them, road test is absolutely necessary. But it does not only need large expenditure, but also asks for a severe test environment. If the vehicle estate, road information or the design of control algorithm and strategy is bad, it is very dangerous. So, as the computer technique developing and the vehicle dynamic model updating, Hardware-In-the-Loop (HIL) technique has been an important method of develop ESP product gradually. Using the ESP HIL test bench will reduce times of road test and ensure the manipulator to be safe. It also saves the money and shortens the period of R&D. It has no doubt it is an effective method to develop ESP quickly.This dissertation, based on study the experiences and achievement of vehicle ESP HIL test bench, at home and abroad, presents in detail the layout of the test bench and the working principle of the parts in the test bench. The ESP HIL test bench is composed of two PC (host and target)and data acquisition card, being connected by TCP/IP, what make up of an xPC Target real time system that simulate the real vehicle. At the early stages of product research, the controller is built by MATLAB/Simulink. Later, when being tested, it will be replaced by single chip machine. The pressure enlarging circuit, solenoid valve drive circuit in the ESP controller developing system and the data acquisition card connect the hardware and software to make sure that the whole system can run in real time and form a closed control system.The develop period ESP HIL test bench is long. Because of time, allowed for the actual situation of the group, this dissertation mainly focuses on the first step of construction of simulation test bench. The general research work is described as followed:1 Learn the development history, current situation and trends of ESP and HIL test bench in detail. Consider the reality of the demand for research to determine the drection and progress.2 Based on analysing ESP HIL test bench at home and abroad and actual situation, make sure the overall layout and specific program of HIL test bench.3 According to the program, choose appropriate hardware to purchase. Construct the hardware part of the test bench. Build data acquisition card model with MATLAB/Simulink on target PC to test the real time ability and demarcate the signal.4 Do research on 15 degrees of freedom vehicle model and vehicle stability control algorithm. Build vehicle dynamic model and ESP model respectively with veDYNA and MATLAB/Simulink to finish the offline simulation program, which is composed of step input steering and double lane tests. Through the off-line simulation, the characters and the working principle could be deeply understand and mastered. At the same time, the practicality and effectiveness are testified.5 Transform the models into C codes with RTW, which is supplied by MATLAB, and download it to the target PC with xPC Target. Run the new models in the target PC to check its real time capability. Update the software model with adding hardware signal into the simulation model to check the feasibility of HIL test bench. This could lay the foundation for later work.The following conclusions can be derived from the study of vehicle stability control system and the construction of HIL simulation test bench:1 Yaw angle rate and slip-angle are very important control parameter of vehicle stability control system.The lateral stability of vehicle can be enhanced by controlling yaw angle rate and slip-angle.2 The HIL simulation test bench, which is constructed based on xPC Target, can both save expenditure and do research work well. With its real time capability and reliability, the HIL test bench is an effective basic equipment for further work.The overall developing work of HIL test bench is not finished because of the lack of time. The task, including manufacturing single chip machine, developing CAN and doing research on the animation of the HIL test bench, is to be done in futher work.