The Development And Application Of The Performance Test Bench Of The Vehicle Braking System

The braking system is one of the most important systems in the vehicle.A series of active safety braking systems based on the hydraulic braking system have been developed,such as Anti-Lock Braking System(ABS),Electronic Stability Control(ESC),Autonomous Braking System(AEB),et al,meanwhile,there are exist some other active safety systems,such as Active Yaw Control(AYC),and Traction Control System(TCS).In these systems,Hydraulic Control Unit(HCU)is one of the most important components,and all these active safety control targets are achieved by the control of the tire slip ratio and the generation of the vehicle yaw moment,which gained by the individual tire braking force utilizing the Hydraulic Control Unit.It is of great meaningful for the understand and development of the vehicle active safety systems to analyze the working principle of different working patterns of the braking system and the HCU,to analyze and measure the working performance parameters of HCU.At present,the market of the active safety systems is mainly monopolized by a few foreign companies,and the independent enterprises are still in the beginning stage,there is a need for the independent enterprises with the measurement and development tools,thus the vehicle braking system performance test bench is developed in this paper,it can measure the braking system performance parameters in high precision,supporting the development and calibration for the independent enterprise products,and offering the verification tools for the control theory of the pilot vehicle active safety systems.In this paper,the history and the classification of braking systems are summarized firstly,the most common and the pilot technology of the braking systems are introduced.The working principles of ABS,ESC,and et al,which based on the most common vehicle hydraulic braking system,are analyzed,and the concerned performance parameters are extracted.And then,the component parts of the HCU are introduced,the test principles of the performance parameters of different components are analyzed,the theoretical foundations of the test bench are formed.The test bench is constructed according to the structural feature of the braking system and the test principles of the performance test.The basic components,the hydraulic scheme and the signal flow are designed,the key part of the test bench are structural designed and type selected.In the last,the performances of the braking system are tested,part of the data are analyzed,the current signals of the HCU motor and the valve are modeled,simulated and analyzed,a method to estimate the rotation speed of the DC brush motor is presented.