d tosi om_fbg
DESCRIPTION
University of Limerick - Politecnico di Torino - presentation for Optical Metrology 2013, Munich - FBG paper.TRANSCRIPT
High-Frequency Optical Fiber Microphone for Condition-Based Maintenance (CBM)
Application
[Optical Metrology, 2013]
Daniele TosiUniversity of Limerick, Optical Fibre Sensors Research Centre
Massimo Olivero, Guido Perrone, Alberto VallanPolitecnico di Torino, Dept. of Electronics and
Telecommunications
Fiber optic microphone
High-frequency optical fiber microphone for condition-based maintenance application
Performance➡ με, nε, <nε sensing
resolution➡ Long-haul sensing
Miniature size➡ Miniature size (∅125μm +
coating)➡ Lightweight, versatile coating
Distribution➡ Time+wavelength
multiplexing➡ Quasi-distributed
Total immunity➡ Totally EMI compatible➡ Fire-safe, passive device
Fiber Bragg grating (FBG)
High-frequency optical fiber microphone for condition-based maintenance application
•Information encoded in FBG optical spectrum•Linear dependance on strain and temperature•1.08 pm/με (10.2 pm/K)•High-speed interrogation
•Information encoded in FBG optical spectrum•Linear dependance on strain and temperature•1.08 pm/με (10.2 pm/K)•High-speed interrogationReflected Bragg wavelength shifts linearly
with variation of tensile strain and temperature
High-speed interrogation
High-frequency optical fiber microphone for condition-based maintenance application
High speed, no scanning elementsShort range, high sensitivitySensitive to backreflection noise
Signal processing
High-frequency optical fiber microphone for condition-based maintenance application
Adaptive filtering•Mitigates the effect of backreflection laser noise•Applied in pre-training conditions
Frequency estimat.•Operate in low SNR, well below -35 dB•Computational complexity increase
High sensitivity, ≲0.1 nεNo real-time detection
FBG multiplexing
High-frequency optical fiber microphone for condition-based maintenance application
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FBG matrixchannel 1channel 2
channel N
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wavel. Wwavel. 2wavel. 1
Architecture
High-frequency optical fiber microphone for condition-based maintenance application
Switch
Laser array
Laser controller
Photodiode
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FBG matrix
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Prototype
High-frequency optical fiber microphone for condition-based maintenance application
Laser(s) Detector
Switch 1x2Circulator
TEC/LDC
Fiber outputDAQ output
DAQ 5kS/s
Frequency response
High-frequency optical fiber microphone for condition-based maintenance application
Voice detection
High-frequency optical fiber microphone for condition-based maintenance application
Intelligibility + peak reproduction
CBM Condition-Based Maintenance
High-frequency optical fiber microphone for condition-based maintenance application
CBM Condition-Based Maintenance
High-frequency optical fiber microphone for condition-based maintenance application
CBM Condition-Based Maintenance
High-frequency optical fiber microphone for condition-based maintenance application
EMI-prone environmentCritical location placementNoisy environmentNetwork structureLong process time
CBM model
High-frequency optical fiber microphone for condition-based maintenance application
Ahmadi, H. and Mollazade, K., "Bearing fault diagnosis of a mine stone crasher by vibration condition monitoring technique," Res. J. Appl. Sci.
Eng. Technol. 1 (2009).
Sound = f(shape) + + f(rotation/contact) + + f(damage)
Warning signal (fm)
CBM model
High-frequency optical fiber microphone for condition-based maintenance application
Ahmadi, H. and Mollazade, K., "Bearing fault diagnosis of a mine stone crasher by vibration condition monitoring technique," Res. J. Appl. Sci.
Eng. Technol. 1 (2009).
CBM model
High-frequency optical fiber microphone for condition-based maintenance application
Ahmadi, H. and Mollazade, K., "Bearing fault diagnosis of a mine stone crasher by vibration condition monitoring technique," Res. J. Appl. Sci.
Eng. Technol. 1 (2009).
Useful region
Future work
High-frequency optical fiber microphone for condition-based maintenance application
FBGsShaker
CFC(4 layer)