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Title: 3D camera assisted fully automated calibration of scanning laser Doppler vibrometers

Abstract

Scanning laser Doppler vibrometers (LDV) are used to measure full-field vibration shapes of products and structures. In most commercially available scanning laser Doppler vibrometer systems the user manually draws a grid of measurement locations on a 2D camera image of the product. The determination of the correct physical measurement locations can be a time consuming and diffcult task. In this paper we present a new methodology for product testing and quality control that integrates 3D imaging techniques with vibration measurements. This procedure allows to test prototypes in a shorter period because physical measurements locations will be located automatically. The proposed methodology uses a 3D time-of-flight camera to measure the location and orientation of the test-object. The 3D image of the time-of-flight camera is then matched with the 3D-CAD model of the object in which measurement locations are pre-defined. A time of flight camera operates strictly in the near infrared spectrum. To improve the signal to noise ratio in the time-of-flight measurement, a time-of-flight camera uses a band filter. As a result of this filter, the laser spot of most laser vibrometers is invisible in the time-of-flight image. Therefore a 2D RGB-camera is used to find the laser-spot of the vibrometer.more » The laser spot is matched to the 3D image obtained by the time-of-flight camera. Next an automatic calibration procedure is used to aim the laser at the (pre)defined locations. Another benefit from this methodology is that it incorporates automatic mapping between a CAD model and the vibration measurements. This mapping can be used to visualize measurements directly on a 3D CAD model. Secondly the orientation of the CAD model is known with respect to the laser beam. This information can be used to find the direction of the measured vibration relatively to the surface of the object. With this direction, the vibration measurements can be compared more precisely with numerical experiments.« less

Authors:
; ; ;  [1]
  1. Op3Mech Research Group, University of Antwerp, Salesianenlaan 90, 2660 Antwerp (Belgium)
Publication Date:
OSTI Identifier:
22608643
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 1740; Journal Issue: 1; Conference: 12. international A.I.VE.LA. Conference on vibration measurements by laser and noncontact techniques: Advances and applications, Ancona (Italy), 29 Jun - 1 Jul 2016; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; BEAMS; CALIBRATION; COMPARATIVE EVALUATIONS; DOPPLER EFFECT; FILTERS; IMAGES; INFRARED SPECTRA; LASER RADIATION; MAPPING; MECHANICAL VIBRATIONS; NOISE; QUALITY CONTROL; SIGNAL-TO-NOISE RATIO; SURFACES; TIME-OF-FLIGHT METHOD

Citation Formats

Sels, Seppe, E-mail: Seppe.Sels@uantwerpen.be, Ribbens, Bart, Mertens, Luc, and Vanlanduit, Steve. 3D camera assisted fully automated calibration of scanning laser Doppler vibrometers. United States: N. p., 2016. Web. doi:10.1063/1.4952688.
Sels, Seppe, E-mail: Seppe.Sels@uantwerpen.be, Ribbens, Bart, Mertens, Luc, & Vanlanduit, Steve. 3D camera assisted fully automated calibration of scanning laser Doppler vibrometers. United States. doi:10.1063/1.4952688.
Sels, Seppe, E-mail: Seppe.Sels@uantwerpen.be, Ribbens, Bart, Mertens, Luc, and Vanlanduit, Steve. 2016. "3D camera assisted fully automated calibration of scanning laser Doppler vibrometers". United States. doi:10.1063/1.4952688.
@article{osti_22608643,
title = {3D camera assisted fully automated calibration of scanning laser Doppler vibrometers},
author = {Sels, Seppe, E-mail: Seppe.Sels@uantwerpen.be and Ribbens, Bart and Mertens, Luc and Vanlanduit, Steve},
abstractNote = {Scanning laser Doppler vibrometers (LDV) are used to measure full-field vibration shapes of products and structures. In most commercially available scanning laser Doppler vibrometer systems the user manually draws a grid of measurement locations on a 2D camera image of the product. The determination of the correct physical measurement locations can be a time consuming and diffcult task. In this paper we present a new methodology for product testing and quality control that integrates 3D imaging techniques with vibration measurements. This procedure allows to test prototypes in a shorter period because physical measurements locations will be located automatically. The proposed methodology uses a 3D time-of-flight camera to measure the location and orientation of the test-object. The 3D image of the time-of-flight camera is then matched with the 3D-CAD model of the object in which measurement locations are pre-defined. A time of flight camera operates strictly in the near infrared spectrum. To improve the signal to noise ratio in the time-of-flight measurement, a time-of-flight camera uses a band filter. As a result of this filter, the laser spot of most laser vibrometers is invisible in the time-of-flight image. Therefore a 2D RGB-camera is used to find the laser-spot of the vibrometer. The laser spot is matched to the 3D image obtained by the time-of-flight camera. Next an automatic calibration procedure is used to aim the laser at the (pre)defined locations. Another benefit from this methodology is that it incorporates automatic mapping between a CAD model and the vibration measurements. This mapping can be used to visualize measurements directly on a 3D CAD model. Secondly the orientation of the CAD model is known with respect to the laser beam. This information can be used to find the direction of the measured vibration relatively to the surface of the object. With this direction, the vibration measurements can be compared more precisely with numerical experiments.},
doi = {10.1063/1.4952688},
journal = {AIP Conference Proceedings},
number = 1,
volume = 1740,
place = {United States},
year = 2016,
month = 6
}
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