Research On Hardware-in-the-loop Simulation And Test Of Electronic Parking Brake System

Electronic Parking Brake is called for short EPB,as an important branch of Brake-by-wire technology,aiming at improving vehicle's safety and driver's comfort.As a result,more and more researchers turn their attention to the study of electronic parking brake system.At present,the development of EPB is mainly based on the road test of vehicle or hardware-in-the-loop test.Although it can be evaluated more directly and effectively to the performance of EPB,however there are many factors limit the practical application of road test,such as long cycle time,expensive cost and repeatability of test.EPB HIL can simulate almost all the actual vehicle test conditions,and it ensures the smooth of road test,aiming at shortening the cycle time of development and reducing the cost of development.(1)The article analyzed the research background and current situation of EPB,briefly described the mechanical structure and working principle of it.Through analysis and comparison to the practical solutions which were formed at home and abroad,the dSPACE is chosen as the simulation and test platform at last,and the architecture of EPB hardware is designed based on this platform.(2)According to EPB control strategy,the control strategy model of it has been established.The actuator model of EPB is mainly on the DC motor and the screw nut mechanism,and in MATLAB/Simulink the static clamping control is simulated,which indicates the accuracy of the model.(3)The EPB hardware-in-the-loop test platform is divided into two aspects:hardware and software design.The hardware design includes the introduction of dSPACE real-time simulation platform,the choice of hardware board,the design of ramp simulation test bench and the calibration of pressure sensor.Then,in terms of software design,this thesis firstly introduces the software environment of MATLAB/Simulink,ASM vehicle dynamic models and real-time interface of RTI.Then build the I/O interface model based on MATLAB/Simulink and design ControlDesk test management interface and control strategy of ramp simulation test bed.(4)Based on the hardware-in-the-loop test platform of EPB,which is extended,building the control function test platform and the fault diagnosis function test platform,and the control function and fault diagnosis function of EPB electronic control unit are tested according to the simulation test conditions respectively.The experiment results not only prove the validity of EPB hardware-in-the-loop test method,but also validate the effectiveness of EPB hardware-in-the-loop test platform.