Research On Automobile Testing System Based On Virtual Instruments

With the rapid development of automobile industry, automobile test in every direction is a problem need solve. The test requirements of automobile capability ask every automobile factory and research people, who work for automobile industry, develop the more facility and more definite automobile test system. But, in the field of modern vehicle performance test, traditional measuring system can not meet the need of modern test because of its inherent shortcomings. With the high speed development of currently computer and software engineering, the advantage of virtual instrument technology in test field is more and more obvious, and virtual instrument evolve as mainstream. At the same time, automobile technology should also develop itself by study the new fruit of each field actively. Therefore, in this thesis, both of virtual instrument and automobile test are combined organic, automobile test system is developed base on virtual instrument technology using flexibility and'extensibility of virtual instrument.In this thesis the author discusses the present situation of automobile test technology at home and abroad, and simply introduces virtual instrument technology; analyzes the signal processing methods which are concerned in building the automobile test system, include the signal crest value domain analysis, time domain analysis and frequency domain analysis; selects the sensor adapt to automobile test, realizes the function of data acquisition, storage and analysis using DAQ data acquisition card of NI company and LabVIEW software:particular introduces the realization of serial port data acquisition function by LabVIEW. The automobile test system based on virtual instrument includes three parts that are engine detection, comfort detection and braking detection. The chief items of engine detection are the engine basic capability detection, no load power detection, liberation speed detection, liberation acceleration detection, noise detection, fuel consumption detection and exhaust gas detection; the chief item of comfort detection is the liberation acceleration detection; the chief items of braking detection are driving speed, braking time, brake distance and braking deceleration.Though the parameter detection and signal processing of automobile capability, comfort and braking, automobile test system is developed using the software Lab VIEW8.6. By simulation experiment, it can be seen that the system can display and store the data collected precisely and steadily, so it is feasible that combine the virtual instrument and automobile test system. In this thesis, the test system operates simply, apt to expand and has better character of currency, can be applied to the automobile production of different model and different brand.