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Title: Dispersive Wave Analysis Using the Chirplet Transform

Abstract

Time-frequency representations (TFR) are a widely used tool to analyze signals of guided waves such as Lamb waves. As a consequence of the uncertainty principle, however, the resolution in time and frequency is limited for all existing TFR methods. Due to the multi-modal and dispersive character of Lamb waves, displacement or energy related quantities can only be allocated to individual modes when they are well-separated in the time-frequency plane.The chirplet transform (CT) has been introduced as a generalization of both the wavelet and Short-time Fourier transform (STFT). It offers additional degrees of freedom to adjust time-frequency atoms which can be exploited in a model-based approach to match the group delay of individual modes. Thus, more exact allocation of quantities of interest is possible.The objective of this research is to use a previously developed adaptive algorithm based on the CT for nondestructive evaluation. Both numerically and experimentally generated data for a single aluminum plate is analyzed to determine the accuracy and robustness of the new method in comparison the classical STFT.

Authors:
;  [1];  [2];  [3];  [1];  [4]
  1. School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA 30332-0355 (United States)
  2. Institute of Applied and Experimental Mechanics, University of Stuttgart, Pfaffenwaldring 9 70569 Stuttgart (Germany)
  3. Department of Psychiatry, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, 02215 (United States)
  4. (United States)
Publication Date:
OSTI Identifier:
21054979
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 894; Journal Issue: 1; Conference: Conference on review of progress in quantitative nondestructive evaluation, Portland, OR (United States), 30 Jul - 4 Aug 2006; Other Information: DOI: 10.1063/1.2718031; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ACCURACY; ALGORITHMS; ALUMINIUM; ATOMS; COMPARATIVE EVALUATIONS; DATA PROCESSING; DEGREES OF FREEDOM; FOURIER TRANSFORMATION; FREQUENCY ANALYSIS; NONDESTRUCTIVE ANALYSIS; PLATES; RESOLUTION; SIGNALS; SOUND WAVES; SURFACES; ULTRASONIC TESTING; UNCERTAINTY PRINCIPLE

Citation Formats

Kerber, Florian, Luangvilai, Kritsakorn, Kuttig, Helge, Niethammer, Marc, Jacobs, Laurence J., and G.W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA 30332-0405. Dispersive Wave Analysis Using the Chirplet Transform. United States: N. p., 2007. Web. doi:10.1063/1.2718031.
Kerber, Florian, Luangvilai, Kritsakorn, Kuttig, Helge, Niethammer, Marc, Jacobs, Laurence J., & G.W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA 30332-0405. Dispersive Wave Analysis Using the Chirplet Transform. United States. doi:10.1063/1.2718031.
Kerber, Florian, Luangvilai, Kritsakorn, Kuttig, Helge, Niethammer, Marc, Jacobs, Laurence J., and G.W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA 30332-0405. Wed . "Dispersive Wave Analysis Using the Chirplet Transform". United States. doi:10.1063/1.2718031.
@article{osti_21054979,
title = {Dispersive Wave Analysis Using the Chirplet Transform},
author = {Kerber, Florian and Luangvilai, Kritsakorn and Kuttig, Helge and Niethammer, Marc and Jacobs, Laurence J. and G.W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA 30332-0405},
abstractNote = {Time-frequency representations (TFR) are a widely used tool to analyze signals of guided waves such as Lamb waves. As a consequence of the uncertainty principle, however, the resolution in time and frequency is limited for all existing TFR methods. Due to the multi-modal and dispersive character of Lamb waves, displacement or energy related quantities can only be allocated to individual modes when they are well-separated in the time-frequency plane.The chirplet transform (CT) has been introduced as a generalization of both the wavelet and Short-time Fourier transform (STFT). It offers additional degrees of freedom to adjust time-frequency atoms which can be exploited in a model-based approach to match the group delay of individual modes. Thus, more exact allocation of quantities of interest is possible.The objective of this research is to use a previously developed adaptive algorithm based on the CT for nondestructive evaluation. Both numerically and experimentally generated data for a single aluminum plate is analyzed to determine the accuracy and robustness of the new method in comparison the classical STFT.},
doi = {10.1063/1.2718031},
journal = {AIP Conference Proceedings},
number = 1,
volume = 894,
place = {United States},
year = {Wed Mar 21 00:00:00 EDT 2007},
month = {Wed Mar 21 00:00:00 EDT 2007}
}
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