Design And Realization For The Testing System Of Steel Ball Based On Virtual Instrument

With the development of science and technology, the requirement on measurement technology is getting more and more important. The application of electronic measurement technique has extended to more fields than ever. Due to limited functions and bulky, traditional electronic measurement equipment is very difficult to meet demands of real work. Thanks to the rapid development of integrated circuit and computer technology, measurement instruments are becoming digitized and intelligentized. Compared with traditional equipment, the new instruments have more functions, higher processing speed, wider bandwidth, friendlier interface, smaller size and better expandability. The prevalence and rocketing development of personal computers give birth to a new kind of instrument, Virtual Instrument (VI).VI is based on PC platform, which makes it convenient to use the software and hardware resources of PC and lets the ability of data processing flexible. With VI, a measure system can be easily built for different requirements of measurement.This paper has combined the technology of virtual instrument, software programming and the technology of eddy current testing, and studied virtual instrument systemically. The author adopts the multi-functional data acquisition card PCI8333 made by the Beijing Zhong Tai Computer Institution, and hangs hardware with software together tightly, and develops the system of virtual instrument based on the data acquisition card. This system includes many functions, for example, signal acquisition, signal processing and saving and output display and so on. Except signal acquisition and conditional circuits are completed by hardware, the others realized by software. This paper mainly completes the design of software.The development of network makes long-distance measurement and control possible. This paper studies the application of virtual instrument in the network. The author adopts the technologies of DataSocket and DCOM/ActiveX, which avoids complex low-layer programming and the problem of the real-time character of data transmission because of low speed of transmission, and realizes the system of networked virtual instrument. This system can realize long-distance acquisition and long-distance output display.This paper systemically analyzes the principle of eddy current testing. Thedesigned system of virtual instrument is applied to eddy current testing, and can measure surface crack in real time. The test proved that the system can effectively measure and analyze surface crack of the steel balls.