基于信号相似度小波重构与时差的胶合木表面声发射源定位

针对声发射（acoustic emission,AE）信号在胶合木表面各向异性传播时的AE源定位问题，提出一种基于信号相似度小波重构与时差的表面AE源定位算法。首先，依据ASTM-E976标准通过铅芯折断在试件表面产生AE源，并采用NI高速采集设备构建基于LabVIEW的3通道AE信号采集平台，采样频率设定为500 kHz。其次，设计一种基于信号相似度的自适应小波重构算法，对原始信号进行降噪并重构AE信号波形。最后，依据试验结果拟合得到AE信号在胶合木表面360°范围内的传播速度公式，结合AE信号的传播规律设计AE源定位算法，并产生AE源以测试定位效果。结果表明，2组胶合木表面的AE源定位误差分别为5.2%、5.3%，基于信号相似度小波重构与时差的胶合木表面AE源定位算法能够有效地确定声发射源的位置。

Localization of Acoustic Emission Sources on Glulam Surface Based on Signal Similarity Wavelet Reconstruction

Aiming at the issue of AE source localization when acoustic emission (AE) signals propagate anisotropically on the surface of glulam,a surface AE source localization algorithm based on signal similarity wavelet reconstruction and time difference was proposed.Firstly,according to the ASTM-E976 standard,the AE source was generated on the surface of the test piece by breaking the lead core,and the NI high-speed acquisition equipment was used to build a 3-channel AE signal acquisition platform based on LabVIEW,and the sampling frequency was set to 500 kHz.Secondly,an adaptive wavelet reconstruction algorithm based on signal similarity was designed to reduce the noise of the original signal and reconstruct the AE signal waveform.Finally,according to the test results,the AE signal propagation speed formula in the range of 360° of the glulam surface was fitted,and the AE source positioning algorithm was designed in conjunction with the propagation law of the AE signal,and the AE source was generated to test the positioning effect.The test results showed that the AE source localization errors of the two groups of glulam surfaces were 5.2% and 5.3%,respectively.The AE source localization algorithm based on signal similarity wavelet reconstruction and time difference can effectively determine the location of the acoustic emission source.