Localization of defects in irregular waveguides by dispersion compensation and pulse compression

Luca De Marchi; Alessandro Marzani; Marco Miniaci; Alessandro Perelli; Nicola Testoni

doi:10.1117/12.2008688

17 April 2013 Localization of defects in irregular waveguides by dispersion compensation and pulse compression

Luca De Marchi, Alessandro Marzani, Marco Miniaci, Alessandro Perelli, Nicola Testoni

Proceedings Volume 8695, Health Monitoring of Structural and Biological Systems 2013; 869517 (2013) https://doi.org/10.1117/12.2008688
Event: SPIE Smart Structures and Materials + Nondestructive Evaluation and Health Monitoring, 2013, San Diego, California, United States

Abstract

In this work a pulse-echo procedure suitable to locate defect-induced reflections in irregular waveguides is proposed. In particular, the procedure extracts the distance of propagation of a guided wave scattered from a defect within the echo signal, revealing thus the source-defect distance. To such purpose, first, a Warped Frequency Transform (WFT) is used to compensate the signal from the dispersion of the guided wave due to the traveled distance in a portion of the waveguide that is assumed as reference. Next, a pulse compression procedure is applied to remove the additional dispersion introduced by the remaining irregular portion of the waveguide. Thanks to this processing the actual distance traveled by the wave in the regular portion of the irregular waveguide is revealed. Thus the proposed strategy extends pulse-echo defect localization procedures based on guided waves to irregular waveguides. Since the processing is based on Fast Fourier Transforms, the algorithm can be easily implemented in real time applications for structural health monitoring. The potential of the procedure is numerically demonstrated by processing Lamb waves propagating in an irregular waveguide composed by aluminum plates with different thicknesses and tapered portions.

Citation Download Citation

Luca De Marchi, Alessandro Marzani, Marco Miniaci, Alessandro Perelli, and Nicola Testoni "Localization of defects in irregular waveguides by dispersion compensation and pulse compression", Proc. SPIE 8695, Health Monitoring of Structural and Biological Systems 2013, 869517 (17 April 2013); https://doi.org/10.1117/12.2008688

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available