Fault Detection Of Anti-lockbanking System Based Onsinglechip

Antilock Braking System(ABS)is one of the important braking devices to protect the safety of automobile.As the loading rate is higher and higher and gradually becomes one of the criteria of auto accessories,fault diagnosis of ABS has become increasingly important.The traditional way of diagnosis depends on the self-check function of ABS,but this way can only detect the electrical failure of ABS.It fails to detect its physical failure,and once ABS actuator fails,its threat is very serious on the traffic safety.Therefore,it is of great significance to explore and perfect the fault diagnosis of ABS actuator.This article first studied the progress made in the fault diagnosis of ABS at home and abroad in recent years,analyses the characteristics of various ways of fault detection,and finally chooses to build a test bench of ABS simulation to expand the research.The ABS electronic control modules in the test bed adopt the self-developed ABS control system based on Single Chip Micyoco(SCM).The control system can not only replace the Electronic Control Unit(ECU)in the ABS to complete calculation and analysis of the wheel speed signal and control solenoid valve to pressurize boost pressure,hold pressure and reduced pressure.It can also realize ABS start with zero speed start at a low speed by changing the controlling logic of single chip,the implementation and can explore the movement rule according to experiment requirement and autonomous control of ABS working rhythm,which makes it easy to better explore the ABS under the health and fault,and enriches the research methods of ABS fault diagnosis.Based on the independent physical simulation experiment platform of ABS,this paper simulates the two most common ABS actuator faults,the fault of brake fluid leakage and the system failure with air of hydraulic system.At the same time,on the test bench the pressure sensor system is also implanted,and the NI acquisition card and the LabVIEW software are used to build a set of signal acquisition system to collect and save the hydraulic signal in the brake cylinder.In the simulation of real vehicle braking,the pressure signal is collected,the data is processed through the drawing,interception,calibration by MATLAB,and the pressure signal diagram of different faults is obtained.After the processing of the signal diagram,the signal pattern of the vehicle in the brakefluid leakage,medium leakage and serious leakage is summarized.At the same time,it also gets the signal characteristics of the hydraulic system mixed into the air fault at high speed and low speed.The experimental results above are in accordance with the theoretical expectation,and verify the feasibility of the ABS fault diagnosis based on single-chip microcomputer drive and pressure sensing,and the investigation of fault diagnosis of ABS actuator is completed.