Design Of Vibration Test System Based On LabVIEW

In modern mechanical industry and mechanical engineering, vibration measurement and analysis is an important part. But the mechanical vibration tests need many elaborate test instruments, which lead to the requiremen to plenty of man power and material resoure on testing work.With the development of computer and software technique, virtual instrument becomes development direction in measurement field, vibration measurement and analysis based on virtual instrment has become the trend of vibration test. So the system for vibration test and analysis is developed in this thesis, which based on PC as hardware platform, laboratory virtual instrument workbench(LabVIEW) developed by National Instruments as software development platform, essential sensor, signal regulation circuit and data acquisition card. Data acquisition and analysis can be achieved by the virtual vibration test and analysis system with the graphic programmer language LabVIEW, at the same time the equipment will be reduced and the cost will be deeply decreased.First, simple introduction on virtual instrument is made in my thesis. Seeond, the theory of vibration signal analysis and the composition of vibration measurement system are analyzed. Last, hardware and software programming of vibration measurement system are designed.Design a data acquisition based on microcontroller in the hardware system. Complete data tarnsoform between computer and data acquisition card over serial port. The superincumbent modular design is exhibited evidently in the software system. The vibration signal sampling and data analysis are operated by system interface, as well as the result are displayed on the computer screen. The main analysis procedure is made up of signal preprocessing, time-domain, frequency domain and joint time and frequency domain. The content involves digital Filter, windowing, time-domain statistical analysis, auto-correlation analysis, as well as Fast Flourier Transfer, auto power spectrum. The Short-time Flourier Transfer are included in the analysis program.The system has main functions of vibration analysis, good expansibility and high cost performance, it is suitable for use of teaching, research and engineering application as analysis tool.