The Design Of A Rotational Switch Torque Test System Based On Labview

Virtual Instrument is a new kind of Instrument which is combined by computer technology and electronics instrument. Usually, it contains PC, modular function hardware and the application software which can perform data analysis, communication and build the graphic user interface. Virtual Instrument makes the computer to be a multi function digital test platform. National Instrument is an American company which first introduces a virtual instrument product. Its DAQ card and LabVIEW share the most part of Virtual Instrument market. The dissertation. introduces the hardware and software design of a rotational switch torque test system which is based on LabVIEW.Firstly, the concept of Virtual Instrument is introduced. Then some related knowledge such as stepping motor, encoder, four wire resistance measurements etc. are explained. Thirdly, the hardware design of the system in detail which includes hardware selection, test PCB design and the interface design of DAQ card and motion control card etc. are described. Fourthly, the design of test software is discussed. The flat file definition, the data acquisition of torque, the implementation of all test items and the measurement of open and contact resistance are all introduced. Again, the test of the whole system and problems and experience during de design are also presented. At last, give a brief conclusion of this thesis and describe some issues need to be improved.