基于Gabor小波和阈值分析的声发射源定位方法

发布时间：2018-02-06 05:08

本文关键词： 计量学声发射时差定位小波变换阈值分析　出处：《压电与声光》2014年04期 　论文类型：期刊论文

【摘要】：针对声发射信号多模态特性和信噪比低的特点,提出了一种将小波变换和阈值分析相结合的声发射源定位方法。对采集到的声发射信号进行信号频谱分析,提取信号主要频率成分之一的小波变换幅值,得到含有多峰值的时域波形。为消除多峰值的影响,将小波变换最大幅值的80%设为阈值。在时频空间下,确定声发射信号中同一频率下同种模态的波到达传感器的时间差,并测量该模态波在板面传播的群速度,实现声发射源定位。在大理石板上进行声发射两点线定位实验,结果证实该方法的确能提高声发射源定位精度,是一种有效的声发射源定位方法。
[Abstract]:Aiming at the multi-mode characteristic and low signal-to-noise ratio (SNR) of acoustic emission signals, a method of acoustic emission source location based on wavelet transform and threshold analysis is proposed. The spectrum of the collected acoustic emission signals is analyzed. The wavelet transform amplitude of one of the main frequency components of the signal is extracted, and the time domain waveform with multiple peaks is obtained. In order to eliminate the influence of the multi-peak value, 80% of the largest value of the wavelet transform is set as the threshold value. In the time-frequency space, 80% of the maximum value of the wavelet transform is set as the threshold value. The time difference of the wave of the same mode in the acoustic emission signal is determined and the group velocity of the wave propagating on the plate surface is measured. The experiment of acoustic emission two-point line location on Dali stone slab shows that this method can improve the accuracy of acoustic emission source location and is an effective method for acoustic emission source location.
【作者单位】：山东省商业职业技术学院信息技术学院;
【分类号】：TN911.7

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