Title :
Multiplexed Fiber Bragg Grating Interrogation System Using a Microelectromechanical Fabry–Perot Tunable Filter
Author :
Allan, William R. ; Graham, Zachary W. ; Zayas, Jose R. ; Roach, Dennis P. ; Horsley, David A.
Author_Institution :
Univ. of California, Davis, CA
Abstract :
This paper describes a fiber Bragg grating strain sensor interrogation system based on a microelectromechanical systems tunable Fabry-Perot filter. The shift in the Bragg wavelength due to strain applied to a sensor fiber is detected by means of a correlation algorithm which was implemented on an embedded digital signal processor. The instrument has a 70 nm tuning range, allowing multiple strain sensors to be multiplexed on the same fiber. The performance of the interrogator was characterized using an optical fiber containing six grating strain sensors embedded in a fiberglass test specimen. The measured root mean square (RMS) strain error was 1.5 microstrain, corresponding to a 1.2 pm RMS error in the estimated wavelength shift. Strain measurements are produced with an update rate of 39 samples/s.
Keywords :
Bragg gratings; embedded systems; fibre optic sensors; mean square error methods; micro-optomechanical devices; multiplexing; optical correlation; optical fibre filters; optical glass; optical tuning; strain measurement; strain sensors; correlation algorithm; embedded digital signal processor; fiberglass test specimen; microelectromechanical Fabry-Perot tunable filter; multiplexed fiber Bragg grating strain sensor interrogation system; root mean square strain error; wavelength 70 nm; Capacitive sensors; Fabry-Perot; Filters; Microelectromechanical systems; Optical fiber sensors; Optical fiber testing; Sensor phenomena and characterization; Sensor systems; Signal processing algorithms; Strain measurement; Microelectromechanical devices; optical fiber transducers; strain measurement;
Journal_Title :
Sensors Journal, IEEE
DOI :
10.1109/JSEN.2009.2024849
