The Basis Of The Virtual Instrument Technology And Its Application

With the development of science and technology, the requirement on measurement technology is getting more and more important. The application of electronic measurement technology has extended to more fields than before. Due to limited functions and big size, traditional electronic measuring equipments are no longer suitable to common purposes. The rapid development of integrated circuit and computer technology gives birth to a new kind of instrument, Virtual Instrument( VI). Compared with traditional equipment, VI characterizes with more functions, higher processing speed, wider bandwidth, friendlier interface, small size and better expandability. It is based on PC platform, which make it convenient to use the software and hardware resources of PC and get the ability of data processing flexible. With VI, a measure system can be easily builded for different requirements.This dissertation discusses the implementation of virtual oscillograph and virtual inductance micrometer. It analyses the sampling theorem and the different mode in Dos and Windows, accomplishing a signal acquisition system in Win32 operation system.This dissertation studies the basic design method of VI, discusses the realtime display of digital signal with the points of data acquisition card, ISA line, Windows 2000 operation system, the calculagraph of Windows, etc. Combined with PC6310 data acquisition card, the programme with the functions of data realtime acquisition and display in Windows 2000 is developed.This dissertation emphasizes on the technology of wave resuming and displaying. Using thrice spline arithmetic on wave resuming, and moving average on reducing noises. The arithmetic module has good independence and can be used in different system repeatedly.Finally, the dissertation develops the storage and print function of VI by using DIB bitmap mode. The whole system has good flexibility and generalization.The system settles a basis for further research and development in different background. Operation results testify the correctness and feasibility of the applied theory and method.