Research On Multi-channel Parallel Dynamic Testing Virtual Instrument Based On LabVIEW

Dynamic testing for the Large and Complex Structure (LCS) in operation state is widely used in characteristics test and dynamic design of mechanical products. Large-storage and multi-channel parallel data acquisition and analysis system based on Virtual Instrument (VI) is required. Now testing instrument that meet the requirements is few. Implementations of VI for dynamic testing are important subjects for inspecting dynamic characteristics of the LCS. With the quick development of science and technology, the requirements for testing instrument are more and more high, and the requirements for hard instrument devices are more, and the cost is too higher. With rapid development of computer technology, software technology, and network technology, VI technique is introduced to dynamic testing for the LCS, which may make up a set of dynamic testing system conveniently. The advantages of adoption of VI consist in instrument functions customization and convenient makeup and way of conversion. Dynamic testing system based on VI for the LCS possesses advantages such as simple makeup, higher performance, short development period, easy maintenance etc. Introduction part in this thesis discusses in detail purpose and meaning for dynamic testing and development of dynamic testing instrument at home and abroad, and introduces VI technology and graphic programming language LabVIEW. Main task in this thesis is to develop multi-channel parallel dynamic testing VI based on personal computer for the LCS. By comparison and analysis, the data acquisition card PCI-4472 is chosen as the main hardware, presented by American National Instruments Company. This system uses the LabVIEW as the software platform. The VI is implemented for dynamic testing including data acquisition, dynamic signal analysis. The main task including are as follows: (1) Multi-function and modularization design methods are applied in the whole system setup. The system includes four modules, such as the data acquisition module, the analysis module, the writing and reading module and data exchange between different software plates. Especially, the data acquisition module realizes triggering acquisition. (2) Dynamic testing VI may acquire and analyze multi-channel data in parallel, and save the data. (3) A dynamic testing is conducted to demonstrate VI's functions including data acquisition, dynamic signal analysis, etc. And analysis result from VI is compared with the result from HP35670. The result shows dynamic test VI's higher performance.