Wavelet-based analysis of time-variant adaptive structures

Abstract

Wavelet analysis is applied to identify the timevariant dynamics of adaptive structures. The wavelet-based power spectrum of the structural response, wavelet-based frequency response function (FRF) and wavelet-based coherence are used to identify continuously and abruptly varying natural frequencies. A cantilever plate with surface-bonded macro fibre compositewhich alters the structural stiffnessis used to demonstrate the application of the methods. The results show that the waveletbased inputoutput characteristicsi.e. the FRF and coherencean identify correctly the dynamics of the analysed time-variant system and reveal the varying natural frequency. The wavelet-based coherence can be used not only for the assessment of the quality of the wavelet-based FRF but also for the identification. This article is part of the theme issue 'Redundancy rules: the continuouswavelet transform comes of age'.