PMID- 29495715
OWN - NLM
STAT- In-Data-Review
LR  - 20180302
IS  - 1520-8524 (Electronic)
IS  - 0001-4966 (Linking)
VI  - 143
IP  - 2
DP  - 2018 Feb
TI  - Remote acoustic detection of mechanical changes in a vibrating plate in an
      unknown reverberant environment.
PG  - 1093
LID - 10.1121/1.5024507 [doi]
AB  - Acoustic radiation from a vibrating mechanical structure subject to broadband
      forcing is inherently dependent on the structure's material, geometry, and
      boundary conditions. Remote measurements of radiated sound can be used to detect 
      mechanical changes (i.e., defects) when compared to known baseline measurements
      from the same structure. However, proper determination of a structure's acoustic 
      signature may not be possible in highly reverberant environments due to
      reverberation contamination. Herein, experimental results are presented for the
      remote acoustic detection of clamped-boundary defects in a nominally 30 x 30 x
      0.3 cm aluminum plate in a reverberant environment. Synthetic Time Reversal (STR)
      is used to estimate the free-field acoustic signature of the plate from
      recordings made in a reverberant environment with a 15-element microphone array
      at signal-to-reverberation ratio levels of -7 to -13 dB in a 100 Hz to 2.0 kHz
      bandwidth. These reconstructed time domain signals are then cross-correlated with
      baseline measurements of a known fully-clamped plate and classified as either
      changed or unchanged. Using common classifier statistics, this approach to remote
      acoustic damage detection using STR is found to be superior to equivalent
      waveform correlation approaches based on unprocessed signals and conventional
      time-domain beamforming outputs.
FAU - Flynn, Tyler J
AU  - Flynn TJ
AD  - Department of Mechanical Engineering, University of Michigan, Ann Arbor, Michigan
      48109-2133, USA.
FAU - Dowling, David R
AU  - Dowling DR
AD  - Department of Mechanical Engineering, University of Michigan, Ann Arbor, Michigan
      48109-2133, USA.
LA  - eng
PT  - Journal Article
PL  - United States
TA  - J Acoust Soc Am
JT  - The Journal of the Acoustical Society of America
JID - 7503051
EDAT- 2018/03/03 06:00
MHDA- 2018/03/03 06:00
CRDT- 2018/03/03 06:00
PHST- 2018/03/03 06:00 [entrez]
PHST- 2018/03/03 06:00 [pubmed]
PHST- 2018/03/03 06:00 [medline]
AID - 10.1121/1.5024507 [doi]
PST - ppublish
SO  - J Acoust Soc Am. 2018 Feb;143(2):1093. doi: 10.1121/1.5024507.