Use of speckle interferometry and modal assurance criterion for identification of component modes

M.A. Caponero, A. Paolozzi, I. Peroni

Research output: Contribution to journalArticle

4 Citations (Scopus)


One of the problems encountered in performing modal analysis is the identification of different modes occurring at close natural frequencies. This paper proposes to face such a problem by an original application of the modal assurance criterion (MAC) that is typically used to verify the reliability of numerical structural models by evaluating the correspondence between numerical and experimental mode shapes. To properly apply the MAC, experimental mode shapes must be retrieved acquiring data at a high number of experimental points suitably distributed on the surface of the structure. Using usual modal analysis techniques based on pointwise transducers, difficulties can be encountered to retrieve mode shapes with the required spatial resolution. In order to overcome such difficulties, Speckle interferometry techniques can be used. This paperproposes a procedure based on the application of a highly reliable MAC evaluated by time average Speckle interferometry for recognising the modes contributing to the stationary vibration patterns. The results obtained from the modal analysis of a thin square plate have shown that the proposed procedure is capable of pointing out the component modes. © 2002 Elsevier Science Ltd. All rights reserved.
Original languageEnglish
Pages (from-to)355 - 367
Number of pages13
JournalOptics and Lasers in Engineering
Issue number4
Publication statusPublished - 2002
Externally publishedYes


All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Atomic and Molecular Physics, and Optics
  • Mechanical Engineering
  • Electrical and Electronic Engineering

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