Combination of Wavelet Transform with EMD to Distinguish Overlapped Lamb Wave Packets
In the non-destructive testing for plate structure with ultrasonic Lamb wave, it is hard to discriminate the overlapped scattered signal from different targets.To solve this problem, Lamb wave signal is decomposed into a set of elemental signals called intrinsic mode functions by empirical mode decomposition (EMD) method first, and the local maximum of the wavelet coefficients of the elemental signals is used to describe the dispersive curve of damage packets.This method can clearly find the differences of two overlapped wave packets based on time-frequency distribution map and the dispersion curve of Lamb-wave.The experiments show that this method is capable of separating the overlapped damage wave components, which is superior to the conventional Hilbert-Huang Transform (H-HT) and wavelet transform methods.
dispersion curve EMD overlapped Lamb wave packets
Ma Ding Shi Lihua Cao Hongfu
National Key Laboratory on Electromagnetic Environmental Effects and Electro-optical Engineering,PLA University of Science and Technology,Nanjing 210007,China
国际会议
哈尔滨
英文
159-165
2013-08-16（万方平台首次上网日期，不代表论文的发表时间）