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Title: Multipoint laser vibrometer for modal analysis

Abstract

Experimental modal analysis of multifrequency vibration requires a measurement system with appropriate temporal and spatial resolution to recover the mode shapes. To fully understand the vibration it is necessary to be able to measure not only the vibration amplitude but also the vibration phase. We describe a multipoint laser vibrometer that is capable of high spatial and temporal resolution with simultaneous measurement of 256 points along a line at up to 80 kHz. The multipoint vibrometer is demonstrated by recovering modal vibration data from a simple test object subject to transient excitation. A practical application is presented in which the vibrometer is used to measure vibration on a squealing rotating disk brake.

Authors:
; ; ; ; ; ;
Publication Date:
OSTI Identifier:
20929737
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Optics; Journal Volume: 46; Journal Issue: 16; Other Information: DOI: 10.1364/AO.46.003126; (c) 2007 Optical Society of America; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; AMPLITUDES; INTERFEROMETRY; KHZ RANGE 01-100; LASERS; MEASURING METHODS; SPATIAL RESOLUTION

Citation Formats

MacPherson, William N., Reeves, Mark, Towers, David P., Moore, Andrew J., Jones, Julian D. C., Dale, Martin, and Edwards, Craig. Multipoint laser vibrometer for modal analysis. United States: N. p., 2007. Web. doi:10.1364/AO.46.003126.
MacPherson, William N., Reeves, Mark, Towers, David P., Moore, Andrew J., Jones, Julian D. C., Dale, Martin, & Edwards, Craig. Multipoint laser vibrometer for modal analysis. United States. doi:10.1364/AO.46.003126.
MacPherson, William N., Reeves, Mark, Towers, David P., Moore, Andrew J., Jones, Julian D. C., Dale, Martin, and Edwards, Craig. Fri . "Multipoint laser vibrometer for modal analysis". United States. doi:10.1364/AO.46.003126.
@article{osti_20929737,
title = {Multipoint laser vibrometer for modal analysis},
author = {MacPherson, William N. and Reeves, Mark and Towers, David P. and Moore, Andrew J. and Jones, Julian D. C. and Dale, Martin and Edwards, Craig},
abstractNote = {Experimental modal analysis of multifrequency vibration requires a measurement system with appropriate temporal and spatial resolution to recover the mode shapes. To fully understand the vibration it is necessary to be able to measure not only the vibration amplitude but also the vibration phase. We describe a multipoint laser vibrometer that is capable of high spatial and temporal resolution with simultaneous measurement of 256 points along a line at up to 80 kHz. The multipoint vibrometer is demonstrated by recovering modal vibration data from a simple test object subject to transient excitation. A practical application is presented in which the vibrometer is used to measure vibration on a squealing rotating disk brake.},
doi = {10.1364/AO.46.003126},
journal = {Applied Optics},
number = 16,
volume = 46,
place = {United States},
year = {Fri Jun 01 00:00:00 EDT 2007},
month = {Fri Jun 01 00:00:00 EDT 2007}
}
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