Wavelet coherence analysis applied to laser vibrometry measurements

G. Zauner; C. Ramsauer; G. Hendorfer

doi:10.1117/12.733815

2 October 2007 Wavelet coherence analysis applied to laser vibrometry measurements

G. Zauner, C. Ramsauer, G. Hendorfer

Proceedings Volume 6763, Wavelet Applications in Industrial Processing V; 67630B (2007) https://doi.org/10.1117/12.733815
Event: Optics East, 2007, Boston, MA, United States

Abstract

Vibration measurement is of great interest in many fields (e.g. mechanical engineering). Laser Doppler Vibrometry (LDV) provides a non-contact method of measuring vibrations very exactly (due to zero mass loading) and greatly increases the investigation capabilities of experimental modal analysis. By applying a standard FFT-algorithm it is possible to analyze the frequency spectrum of the vibrating structure. To overcome many of the shortcomings of classical Fourier-based signal analysis, which are mainly the result of neglecting time resolution, the wavelet transform has been established as an important technique in time-frequency analysis combining high temporal resolution with good frequency resolution. By applying complex wavelets (e.g. the Morlet wavelet) amplitude and phase information can be extracted from the analyzed signal and time is kept as an additional parameter which allows measurement of signal coherence over time as well. The aim of this work is to achieve accurate and reliable quantitative measurements for the characterization of the vibration characteristics of different skis (even when measured under harsh industrial conditions). In this regard, coherence is very sensitive to fluctuations of linearity in phase, relatively less so to nonlinear fluctuations of amplitude and completely insensitive to linear fluctuations in amplitude. Thus, the application of wavelet coherence analysis can give additional detailed insight into the dynamics of vibrations. Experimental results of laser vibrometry measurements are presented and the wavelet-based coherence approach is discussed and compared to classical Fourier methods in order to show the advantages of the wavelet-based representation.

Citation Download Citation

G. Zauner, C. Ramsauer, and G. Hendorfer "Wavelet coherence analysis applied to laser vibrometry measurements", Proc. SPIE 6763, Wavelet Applications in Industrial Processing V, 67630B (2 October 2007); https://doi.org/10.1117/12.733815

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available

Members: $17.00

Non-members: $21.00 ADD TO CART

PROCEEDINGS
9 PAGES

DOWNLOAD PAPER SAVE TO MY LIBRARY

GET CITATION

RIGHTS & PERMISSIONS

Get copyright permission Get copyright permission on Copyright Marketplace

KEYWORDS

Wavelets

Vibrometry

Laser Doppler velocimetry

Doppler effect

Time-frequency analysis

Temporal resolution

Continuous wavelet transforms

Show All Keywords

Keywords/Phrases

Search In:

Publication Years