Acoustic emission source localization and velocity determination of the fundamental mode A0 using wavelet analysis and a Newton-based optimization technique

Francesco Ciampa, Michele Meo

Research output: Contribution to journalArticle

95 Citations (Scopus)
287 Downloads (Pure)

Abstract

This paper investigates the development of an in situ impact detection monitoring system able to identify in real-time the acoustic emission location. The proposed algorithm is based on the differences of stress waves measured by surface-bonded piezoelectric transducers. A joint time-frequency analysis based on the magnitude of the continuous wavelet transform was used to determine the time of arrival of the wavepackets. A combination of unconstrained optimization technique associated with a local Newton's iterative method was employed to solve a set of nonlinear equations in order to assess the impact location coordinates and the wave speed. With the proposed approach, the drawbacks of a triangulation method in terms of estimating a priori the group velocity and the need to find the best time-frequency technique for the time-of-arrival determination were overcome. Moreover, this algorithm proved to be very robust since it was able to converge from almost any guess point and required little computational time. A comparison between the theoretical and experimental results carried out with piezoelectric film (PVDF) and acoustic emission transducers showed that the impact source location and the wave velocity were predicted with reasonable accuracy. In particular, the maximum error in estimation of the impact location was less than 2% and about 1% for the flexural wave velocity.
Original languageEnglish
Article number045027
JournalSmart Materials and Structures
Volume19
Issue number4
DOIs
Publication statusPublished - 2010

Fingerprint Dive into the research topics of 'Acoustic emission source localization and velocity determination of the fundamental mode A<sub>0</sub> using wavelet analysis and a Newton-based optimization technique'. Together they form a unique fingerprint.

Cite this