The Virtual Instrument Development And Application In Automobile Transmission Life Testing Condition Monitoring

With the development of computer technology, the traditional equipment began computerized. Virtual Instrument is a perfect product that is made of modern computer technology, Instruments technology and other new technologies .its powerful role has been entirely beyond the concept of the instrument itself. Equipment condition monitoring technique can ensure product quality, enhance economic efficiency, eliminate hidden faults and avoid accidents.The main purpose of this paper is written to explain the Automobile Transmission Life Test condition monitoring system. The Automobile Transmission Life Test is a special device tested automobile transmission life. The various parameters Measured by it better provide the basis for the production of automobile transmission. The monitoring torque, rotational speed, temperature and vibration of transmission is the purpose of the system designed, simultaneity handling of emerging issues (such as giving an alarm, parking, starting cooling equipment etc). To achieve this end, the system uses a Virtual Instrument technology building monitoring system hardware platform, and uses Borland C + + Builder and Lab Windows/CVI for software development platform. This monitoring system in the development process, mainly the following:Firstly, the condition monitoring hardware based on Virtual Instrument is explained,espically main hardware such as sensor ,A/D card etc. Secondly, as software development platform, Borland C++Builder and Lab Windows/CVI are introduced. After several tests, applications software development at the course, using different operating system (windows98 and windowsNT) and using different programming language (assemble language and advanced language function) do test that the accuracy of results measured is different. The reason is analyzed. Counting and Timing were used to measure torque and rotational speed, and measuring accuracy and speed are compared. Measurement accuracy by Timing was influenced the operating system, and measurement accuracy by Counting was influenced the speed of the CPU. Finally, an analysis of the fault of the transmission, it is necessary to diagnose the gear faults because 60% of the faults are due to appear in gear. We design a virtual time-domain spectrum analyzer. it can be carried out gear vibration signals in time domain analysis, power spectrum analysis, amplitude spectrum analysis, logarithm spectrum analysis...