Decomposition of multi-mode signals using dispersion curves and Bayesian linear regression

Marcus Haywood-Alexander, Nikolaos Dervilis, Keith Worden, Gordon B. Dobie, Timothy J. Rogers

Research output: Chapter in Book/Report/Conference proceedingConference contribution book

1 Downloads (Pure)


For certain structure types and damage sizes, guided waves offer some distinct advantages for damage detection, such as range and sizing potential, greater sensitivity and cost effectiveness. Guided waves exhibit multiple modes; for Lamb waves there are two types; symmetric and antisymmetric. In damage detection regimes, information and features of individual modes, which propagate from a single source, are useful for localisation and sizing of damage. This facet leads to the motivation to decompose a single signal into the individual modes that are received in the wave-packet. Decomposition of wave modes is possible in full-field Lamb wave data from a forward-backward, two-dimensional Fourier transform method that involves dispersion curve information; though this method cannot be applied directly to signals at a single location. By using this method, the expected nominal waves can be determined for a given propagation distance; i.e. the individual wave modes expected to be present regardless of damage. In the presence of damage, residual signals will be present which contain information on the damage. In this paper, a Bayesian linear regression technique is used to decompose single multi-mode signals into their individual wave modes, which is then used to determine any residual signals. This decomposition is made by determining the expected shape and size of individual mode signals from the full-field decomposed waves. The information inferred by this method, both before and after the wave has propagated through damage, is studied.

Original languageEnglish
Title of host publicationHealth Monitoring of Structural and Biological Systems XV
EditorsPaul Fromme, Zhongqing Su
Place of PublicationBellingham, Washington
Number of pages12
ISBN (Electronic)9781510640153
Publication statusPublished - 6 May 2021
EventHealth Monitoring of Structural and Biological Systems XV 2021 - Virtual, United States
Duration: 22 Mar 202126 Mar 2021

Publication series

NameProceedings of SPIE - The International Society for Optical Engineering
ISSN (Print)0277-786X
ISSN (Electronic)1996-756X


ConferenceHealth Monitoring of Structural and Biological Systems XV 2021
Country/TerritoryUnited States


  • dispersion curves
  • guided wave
  • lamb wave
  • mode decomposition


Dive into the research topics of 'Decomposition of multi-mode signals using dispersion curves and Bayesian linear regression'. Together they form a unique fingerprint.

Cite this