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With the progress of science and technology, cars have become an important part inmodern life in the car, which’s safety performance is growing more and more concern. Brakeconducts as a key component of vehicle brake system, and the braking performance playsdirectly impact on cars’safety. For current braking safety performance issues of vehiclebrakes, large number of domestic and foreign documents, and the basic research status ofvehicle brakes, this thesis has researched on the vehicle brakes’gap monitoring system.Based on performance requirements and disc brake working theory, brakes’gap issubject to the object of study and the overall design of brakes’gap monitoring system hasbeen proposed. In the system hardware, this thesis has completed system hardware design andthe conditioning circuit design; In the system software, adopting multi-threading technology,this thesis has completed the data acquisition and processing, data protection, communicationprotocols and database design, achieved the data acquisition show, history data reading, tableanalysis, printing, help files and so on, and has fulfilled the functional requirements of thesystem software.In the research process of the filter conditioning circuit, and with Multisim10.0simulation software, this thesis has completed DC sweep analysis, AC analysis, sensitivityanalysis and zero-pole analysis of the fifth-order Butterworth filter circuit. The analysiscomprehensively showed that the fifth-order Butterworth filter circuit has a good and stableDC characteristics and AC characteristics.In the process of experiments, by changing the gap between the brake disc and thefriction disc, the brakes’gap monitoring system achieved real-time data acquisition, recordedthe value of brakes’gap and completed the test of corresponding functions. The resultsshowed that the brakes’gap monitoring system based on LabWindows / CVI is simple and stable, which has friendly interfaces, is operated easily and can meet the testing requirements.The brakes’gap monitoring system can experimentally and theoretically be used in fieldtesting.
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