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Title: Full-field vibration measurements of the violin using digital stroboscopic holographic interferometry and electromagnetic stimulation of the strings

Abstract

We developed a setup in which the strings of the violin are driven electromagnetically, and the resulting vibration of the instrument is measured with digital stroboscopic holography. A 250 mW single mode green laser beam is chopped using an acousto-optic modulator, generating illumination pulses of 2% of the vibration period. The phase of the illumination pulse is controlled by a programmable function generator so that digital holograms can be recorded on a number of subsequent time positions within the vibration phase. From these recordings, the out of plane motion as a function of time is reconstructed in full field. We show results of full-field vibration amplitude and vibration phase maps, and time resolved full-field deformations of the violin back plane. Time resolved measurements show in detail how the deformation of the violin plane changes as a function of time at different frequencies. We found very different behavior under acoustic stimulation of the instrument and when using electromagnetic stimulation of a string. The aim of the work it to gather data which can be used in power flow calculations to study how the energy of the strings is conducted to the body of the violin and eventually is radiated as sound.

Authors:
; ; ;  [1]
  1. University of Antwerp, Laboratory of Biophysics and Biomedical Physics, Groenenborgerlaan 171, 2020 Antwerp (Belgium)
Publication Date:
OSTI Identifier:
22608640
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; AMPLITUDES; BEAMS; DEFORMATION; FUNCTION GENERATORS; HOLOGRAPHY; ILLUMINANCE; INTERFEROMETRY; LASER RADIATION; MECHANICAL VIBRATIONS; SOUND WAVES; STIMULATION; TIME DEPENDENCE; TIME RESOLUTION

Citation Formats

Keersmaekers, Lissa, Keustermans, William, E-mail: william.keustermans@uantwerpen.be, De Greef, Daniël, and Dirckx, Joris J. J. Full-field vibration measurements of the violin using digital stroboscopic holographic interferometry and electromagnetic stimulation of the strings. United States: N. p., 2016. Web. doi:10.1063/1.4952664.
Keersmaekers, Lissa, Keustermans, William, E-mail: william.keustermans@uantwerpen.be, De Greef, Daniël, & Dirckx, Joris J. J. Full-field vibration measurements of the violin using digital stroboscopic holographic interferometry and electromagnetic stimulation of the strings. United States. doi:10.1063/1.4952664.
Keersmaekers, Lissa, Keustermans, William, E-mail: william.keustermans@uantwerpen.be, De Greef, Daniël, and Dirckx, Joris J. J. Tue . "Full-field vibration measurements of the violin using digital stroboscopic holographic interferometry and electromagnetic stimulation of the strings". United States. doi:10.1063/1.4952664.
@article{osti_22608640,
title = {Full-field vibration measurements of the violin using digital stroboscopic holographic interferometry and electromagnetic stimulation of the strings},
author = {Keersmaekers, Lissa and Keustermans, William, E-mail: william.keustermans@uantwerpen.be and De Greef, Daniël and Dirckx, Joris J. J.},
abstractNote = {We developed a setup in which the strings of the violin are driven electromagnetically, and the resulting vibration of the instrument is measured with digital stroboscopic holography. A 250 mW single mode green laser beam is chopped using an acousto-optic modulator, generating illumination pulses of 2% of the vibration period. The phase of the illumination pulse is controlled by a programmable function generator so that digital holograms can be recorded on a number of subsequent time positions within the vibration phase. From these recordings, the out of plane motion as a function of time is reconstructed in full field. We show results of full-field vibration amplitude and vibration phase maps, and time resolved full-field deformations of the violin back plane. Time resolved measurements show in detail how the deformation of the violin plane changes as a function of time at different frequencies. We found very different behavior under acoustic stimulation of the instrument and when using electromagnetic stimulation of a string. The aim of the work it to gather data which can be used in power flow calculations to study how the energy of the strings is conducted to the body of the violin and eventually is radiated as sound.},
doi = {10.1063/1.4952664},
journal = {AIP Conference Proceedings},
number = 1,
volume = 1740,
place = {United States},
year = {Tue Jun 28 00:00:00 EDT 2016},
month = {Tue Jun 28 00:00:00 EDT 2016}
}
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