A Lamb wave signal processing method for damage diagnosis in the plate structure

In this work, a damage location method for plate-like structures is developed based on Lamb wave signal processing using matching pursuit method, which is employed to decompose Lamb wave signals into a linear expansion of several chirplet atoms using a fast realization algorithm. The relationship between Lamb wave dispersion and the chirplet chirp rate is established, which can be used to identify the modes of Lamb waves. Then a method for damage location is developed based on the difference between the baseline and the damaged signals. The effectiveness and accuracy of the proposed method in identifying the modes and in locating defects are demonstrated through experimental tests on the isotropic plate structure and honeycomb sandwich composite structure.