Abstract
A pulsed-laser ablation method for non-contact experimental vibration analysis of completely submerged underwater structures is proposed. Although impact testing with an impulse hammer is commonly used for vibration analysis due to its simplicity, impact testing has limited use in underwater conditions. An input-detection-free frequency response function measurement in water will greatly contribute to the development of high-precision and high-speed positioning autonomous underwater vehicles, underwater vehicle-manipulators, underwater robots, submarines, etc., which are used in dangerous conditions (e.g., deep oceans, under ice, and nuclear reactor plants). To achieve these high-performance underwater systems, vibrations due to hydrodynamic parameters (such as added mass, buoyant force, drag force, and damping coefficient) should be suppressed, and vibration tests should be conducted on the actual equipment submerged in water. The proposed method yields the frequency response function by applying a pulsed-laser-ablation excitation force to an underwater structure and measuring the output using a laser Doppler vibrometer. Because the direction, strength, and effective duration of the pulsed-laser-ablation force are essentially constant, this force can be estimated by measuring these properties in advance. Hence, the proposed method realizes input-detection-free frequency response function measurements in underwater conditions.
| Original language | English |
|---|---|
| Pages (from-to) | 3649-3658 |
| Number of pages | 10 |
| Journal | JVC/Journal of Vibration and Control |
| Volume | 22 |
| Issue number | 17 |
| DOIs | |
| Publication status | Published - 2016 Oct 1 |
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Keywords
- cavitation bubble
- frequency response function
- laser ablation
- modal analysis
- non-contact vibration test
- Underwater structure
ASJC Scopus subject areas
- Automotive Engineering
- Materials Science(all)
- Aerospace Engineering
- Mechanics of Materials
- Mechanical Engineering
Cite this
Dynamic characterizations of underwater structures using non-contact vibration test based on nanosecond laser ablation in water : Investigation of cavitation bubbles by visualizing shockwaves using the Schlieren method. / Hosoya, Naoki; Kajiwara, Itsuro; Umenai, Koh.
In: JVC/Journal of Vibration and Control, Vol. 22, No. 17, 01.10.2016, p. 3649-3658.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Dynamic characterizations of underwater structures using non-contact vibration test based on nanosecond laser ablation in water
T2 - Investigation of cavitation bubbles by visualizing shockwaves using the Schlieren method
AU - Hosoya, Naoki
AU - Kajiwara, Itsuro
AU - Umenai, Koh
PY - 2016/10/1
Y1 - 2016/10/1
N2 - A pulsed-laser ablation method for non-contact experimental vibration analysis of completely submerged underwater structures is proposed. Although impact testing with an impulse hammer is commonly used for vibration analysis due to its simplicity, impact testing has limited use in underwater conditions. An input-detection-free frequency response function measurement in water will greatly contribute to the development of high-precision and high-speed positioning autonomous underwater vehicles, underwater vehicle-manipulators, underwater robots, submarines, etc., which are used in dangerous conditions (e.g., deep oceans, under ice, and nuclear reactor plants). To achieve these high-performance underwater systems, vibrations due to hydrodynamic parameters (such as added mass, buoyant force, drag force, and damping coefficient) should be suppressed, and vibration tests should be conducted on the actual equipment submerged in water. The proposed method yields the frequency response function by applying a pulsed-laser-ablation excitation force to an underwater structure and measuring the output using a laser Doppler vibrometer. Because the direction, strength, and effective duration of the pulsed-laser-ablation force are essentially constant, this force can be estimated by measuring these properties in advance. Hence, the proposed method realizes input-detection-free frequency response function measurements in underwater conditions.
AB - A pulsed-laser ablation method for non-contact experimental vibration analysis of completely submerged underwater structures is proposed. Although impact testing with an impulse hammer is commonly used for vibration analysis due to its simplicity, impact testing has limited use in underwater conditions. An input-detection-free frequency response function measurement in water will greatly contribute to the development of high-precision and high-speed positioning autonomous underwater vehicles, underwater vehicle-manipulators, underwater robots, submarines, etc., which are used in dangerous conditions (e.g., deep oceans, under ice, and nuclear reactor plants). To achieve these high-performance underwater systems, vibrations due to hydrodynamic parameters (such as added mass, buoyant force, drag force, and damping coefficient) should be suppressed, and vibration tests should be conducted on the actual equipment submerged in water. The proposed method yields the frequency response function by applying a pulsed-laser-ablation excitation force to an underwater structure and measuring the output using a laser Doppler vibrometer. Because the direction, strength, and effective duration of the pulsed-laser-ablation force are essentially constant, this force can be estimated by measuring these properties in advance. Hence, the proposed method realizes input-detection-free frequency response function measurements in underwater conditions.
KW - cavitation bubble
KW - frequency response function
KW - laser ablation
KW - modal analysis
KW - non-contact vibration test
KW - Underwater structure
UR - http://www.scopus.com/inward/record.url?scp=84985894869&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84985894869&partnerID=8YFLogxK
U2 - 10.1177/1077546314564693
DO - 10.1177/1077546314564693
M3 - Article
VL - 22
SP - 3649
EP - 3658
JO - JVC/Journal of Vibration and Control
JF - JVC/Journal of Vibration and Control
SN - 1077-5463
IS - 17
ER -