Flaw localization using the reassigned spectrogram on laser-generated and detected Lamb modes.

Christine Valle; Jerrol W Littles

doi:10.1016/s0041-624x(02)00249-4

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PubMed · 12109543

Flaw localization using the reassigned spectrogram on laser-generated and detected Lamb modes.

Christine Valle·Jerrol W Littles

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Abstract

Rapid, accurate inspection of metallic plates using broadband guided waves has traditionally been limited by the multi-mode, highly dispersive nature of these waves; current practice typically restricts either the type of mode generated or detected, and/or its frequency range. The current study presents an effective alternative procedure by combining a novel digital signal processing technique, the reassigned spectrogram, with laser generated and detected Lamb waves. The reassigned spectrogram is used to characterize the modal and frequency content of a single ultrasonic signal as a function of time, enabling a procedure to locate flaws in an aluminum plate specimen.

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Aluminum Signal Processing, Computer-Assisted Ultrasonics Journal Article Research Support, U.S. Gov't, Non-P.H.S.

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Christine Valle, Jerrol W Littles. 2002. Flaw localization using the reassigned spectrogram on laser-generated and detected Lamb modes.. https://doi.org/10.1016/s0041-624x(02)00249-4

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