MEASURING MODE SHAPES WITH A CONTINUOUSLY SCANNING LASER VIBROMETER —HILBERT TRANSFORM APPROACH
✍ Scribed by M.S. KANG; A.B. STANBRIDGE; T.G. CHANGH.; H.S. KIM
- Publisher
- Elsevier Science
- Year
- 2002
- Tongue
- English
- Weight
- 194 KB
- Volume
- 16
- Category
- Article
- ISSN
- 0888-3270
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✦ Synopsis
This paper is concerned with vibration deflection-shape measurement techniques for a sinusoidally excited structure, using a continuously scanning laser Doppler vibrometer (CSLV). The CSLV output signal is an amplitude-modulated vibration in which the excitation signal is modulated by the (complex) deflection shape, and thus the deflection shape, defined along a scan line, can be derived from the envelope and phase information in the CSLV output signal. In this work, a Hilbert transform based approach has been proposed for measurement of deflection shapes. This is a simple technique, which has advantages over previously described demodulation and Fourier transform approaches. The feasibility of the proposed technique is illustrated, along with results of an experimental demonstration.