Vibration testing based on impulse response excited by laser ablation

Itsuro Kajiwara, Naoki Hosoya

Research output: Contribution to journalArticle

32 Citations (Scopus)

Abstract

This paper proposes an innovative vibration testing method based on impulse response excited by laser ablation. In conventional vibration testing using an impulse hammer, high-frequency elements of over tens of kilohertz are barely present in the excitation force. A pulsed high-power YAG laser is used in this study for producing an ideal impulse force on a structural surface. Illuminating a point on a metal with the well-focused YAG laser, laser ablation is caused by generation of plasma on the metal. As a result, an ideal impulse excitation force generated by laser ablation is applied to the point on the structure. Therefore, it is possible to measure high-frequency FRFs due to the laser excitation. A water droplet overlay on the metal is used to adjust the force magnitude of laser excitation. An aluminum block that has nine natural frequencies below 40 kHz is employed as a test piece. The validity of the proposed method is verified by comparing the FRFs of the block obtained by the laser excitation, impulse hammer, and finite element analysis. Furthermore, the relationship between accuracy of FRF measurements and sensitivity of sensors is investigated.

Original languageEnglish
Pages (from-to)5045-5057
Number of pages13
JournalJournal of Sound and Vibration
Volume330
Issue number21
DOIs
Publication statusPublished - 2011 Oct 10

Fingerprint

Laser excitation
Laser ablation
Impulse response
laser ablation
impulses
Hammers
vibration
Testing
hammers
Metals
excitation
High power lasers
YAG lasers
Pulsed lasers
metals
Natural frequencies
lasers
Aluminum
Plasmas
Finite element method

ASJC Scopus subject areas

  • Acoustics and Ultrasonics
  • Condensed Matter Physics
  • Mechanical Engineering
  • Mechanics of Materials

Cite this

Vibration testing based on impulse response excited by laser ablation. / Kajiwara, Itsuro; Hosoya, Naoki.

In: Journal of Sound and Vibration, Vol. 330, No. 21, 10.10.2011, p. 5045-5057.

Research output: Contribution to journalArticle

@article{e6d892f2ffb04fdb86a5206fb446723c,
title = "Vibration testing based on impulse response excited by laser ablation",
abstract = "This paper proposes an innovative vibration testing method based on impulse response excited by laser ablation. In conventional vibration testing using an impulse hammer, high-frequency elements of over tens of kilohertz are barely present in the excitation force. A pulsed high-power YAG laser is used in this study for producing an ideal impulse force on a structural surface. Illuminating a point on a metal with the well-focused YAG laser, laser ablation is caused by generation of plasma on the metal. As a result, an ideal impulse excitation force generated by laser ablation is applied to the point on the structure. Therefore, it is possible to measure high-frequency FRFs due to the laser excitation. A water droplet overlay on the metal is used to adjust the force magnitude of laser excitation. An aluminum block that has nine natural frequencies below 40 kHz is employed as a test piece. The validity of the proposed method is verified by comparing the FRFs of the block obtained by the laser excitation, impulse hammer, and finite element analysis. Furthermore, the relationship between accuracy of FRF measurements and sensitivity of sensors is investigated.",
author = "Itsuro Kajiwara and Naoki Hosoya",
year = "2011",
month = "10",
day = "10",
doi = "10.1016/j.jsv.2010.09.036",
language = "English",
volume = "330",
pages = "5045--5057",
journal = "Journal of Sound and Vibration",
issn = "0022-460X",
publisher = "Academic Press Inc.",
number = "21",

}

TY - JOUR

T1 - Vibration testing based on impulse response excited by laser ablation

AU - Kajiwara, Itsuro

AU - Hosoya, Naoki

PY - 2011/10/10

Y1 - 2011/10/10

N2 - This paper proposes an innovative vibration testing method based on impulse response excited by laser ablation. In conventional vibration testing using an impulse hammer, high-frequency elements of over tens of kilohertz are barely present in the excitation force. A pulsed high-power YAG laser is used in this study for producing an ideal impulse force on a structural surface. Illuminating a point on a metal with the well-focused YAG laser, laser ablation is caused by generation of plasma on the metal. As a result, an ideal impulse excitation force generated by laser ablation is applied to the point on the structure. Therefore, it is possible to measure high-frequency FRFs due to the laser excitation. A water droplet overlay on the metal is used to adjust the force magnitude of laser excitation. An aluminum block that has nine natural frequencies below 40 kHz is employed as a test piece. The validity of the proposed method is verified by comparing the FRFs of the block obtained by the laser excitation, impulse hammer, and finite element analysis. Furthermore, the relationship between accuracy of FRF measurements and sensitivity of sensors is investigated.

AB - This paper proposes an innovative vibration testing method based on impulse response excited by laser ablation. In conventional vibration testing using an impulse hammer, high-frequency elements of over tens of kilohertz are barely present in the excitation force. A pulsed high-power YAG laser is used in this study for producing an ideal impulse force on a structural surface. Illuminating a point on a metal with the well-focused YAG laser, laser ablation is caused by generation of plasma on the metal. As a result, an ideal impulse excitation force generated by laser ablation is applied to the point on the structure. Therefore, it is possible to measure high-frequency FRFs due to the laser excitation. A water droplet overlay on the metal is used to adjust the force magnitude of laser excitation. An aluminum block that has nine natural frequencies below 40 kHz is employed as a test piece. The validity of the proposed method is verified by comparing the FRFs of the block obtained by the laser excitation, impulse hammer, and finite element analysis. Furthermore, the relationship between accuracy of FRF measurements and sensitivity of sensors is investigated.

UR - http://www.scopus.com/inward/record.url?scp=79960560098&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=79960560098&partnerID=8YFLogxK

U2 - 10.1016/j.jsv.2010.09.036

DO - 10.1016/j.jsv.2010.09.036

M3 - Article

VL - 330

SP - 5045

EP - 5057

JO - Journal of Sound and Vibration

JF - Journal of Sound and Vibration

SN - 0022-460X

IS - 21

ER -