Application of Instantaneous Parameter Characteristic in Active Lamb Wave Based Monitoring of Plate Structural Health

Abstract

In the active Lamb wave based monitoring of plate structural health, it is difficult to extract damage information from active Lamb waves based on single sensor collection. Based on the Hilbert–Huang transform (HHT) instantaneous processing method, this paper proposes to study the damage information carried by a single sensor monitoring signal from the instantaneous parameter characteristics of the signal. The instantaneous phase change caused by the phase difference between the damage scattering wave and the direct wave is studied. The change of the marginal spectrum amplitude in the effective range caused by the damage scattering wave is studied in continuous multiple frequency bands. Finally, the damage information extraction based on a single sensor monitoring signal is realized. From the model analysis and experimental results, it is reliable and feasible to realize the active Lamb wave based monitoring of plate structural health according to the instantaneous parameter change characteristics from a single sensor signal.

Thin Copper Plate Defect Detection Based on Lamb Wave Generated by Pulsed Laser in Combination with Laser Heterodyne Interference Technique

“…Furthermore, time-frequency domain analysis has been proposed to retrieve more accurate and comprehensive information. The time-frequency domain method frequently utilizes techniques such as short-time Fourier transform (STFT), wavelet transform, Hilbert-Huang transform (HHT), Wigner-Ville Distribution (WVD) and Cohen Class Distributions [35][36][37][38]. STFT exhibits limited time resolution due to its fixed window width.…”