Research On Data Acquisition And Multi-function Analysis System Based On Mixed Programming

The advent of the information age has made the mechanical equipment in industrial production develop in the direction of intelligence,precision and complexity.At the same time,it has promoted the wide application of testing and analysis technology.Based on test analysis technology and virtual instrument technology,a test and analysis system with large capacity signal acquisition,multi-function data processing and analysis is designed and developed by using mixed programming method.The user interface and data acquisition card driver are programmed by Delphi.In the interface control program of data acquisition card,multi-thread working mode and buffer queue technology are used to support continue large-capacity data acquisition and storage of eight channels.Depending on the powerful signal processing,analysis and graphics display functions of MATLAB,various algorithms are compiled.The Dynamic Link Library(DLL)is formed by using Component Object Model(COM)technology.In Delphi interface,all algorithms of MATLAB are invoked to realize multi-function signal processing and analysis.Through application of mixed programming technology,the functions of test system are expanded,thirty two signal processing and analysis methods are provided for the test system,and it is more convenient for the improvement and update of the later system functions.A time-frequency combination analysis method composed of two or three time-frequency analysis methods is proposed and implemented,such as wavelet decomposition and fast Fourier transform(FFT),wavelet de-noising and FFT,empirical mode decomposition and Wigner-Ville Distribution(EMD-WVD),wavelet packet de-noising and FFT,EMD-FFT,wavelet packet decomposition and ensemble empirical mode decomposition and FFT(EEMD-FFT).The time-frequency combination analysis method has good effect on feature extraction of non-stationary signals in time-frequency domain,which not only expands the time-frequency analysis method,but also provides a new idea for time-frequency analysis methods.During the development process,the reliability and effect of each module and function are verified by using simulation signals.After the development,the fault diagnosis and engine signal source analysis experiments of a certain type of grinding wheel are carried out.The reliability and practicability of the test and analysis system in the field of signal processing and analysis are verified by the cross-validation method of comparison of various analysis results.The developed test and analysis system can be applied to signal acquisition and analysis,working condition monitoring and fault diagnosis of mechanical equipment,especially in the analysis of non-stationary signals.