Cantilever Beam with a Single Fiber Bragg Grating to Measure Temperature and Transversal Force Simultaneously

Abstract

This work investigates a new interrogation method of a fiber Bragg grating (FBG) sensor based on longer and shorter wavelengths to distinguish between transversal forces and temperature variations. Calibration experiments were carried out to examine the sensor’s repeatability in response to the transversal forces and temperature changes. An automated calibration system was developed for the sensor’s characterization, calibration, and repeatability testing. Experimental results showed that the FBG sensor can provide sensor repeatability of 13.21 pm and 17.015 pm for longer and shorter wavelengths, respectively. The obtained calibration coefficients expressed in the linear model using the matrix enabled the sensor to provide accurate predictions for both measurements. Analysis of the calibration and experiment results implied improvements for future work. Overall, the new interrogation method demonstrated the potential to employ the FBG sensing technique where discrimination between two/three measurands is needed.

Evaluation of a Novel Spectral Pair of a Chirp FBG Embedded in a Cantilever Beam for Simultaneous Temperature and Transverse Forces Measurement

“…The error % with respect to its shift range is found only 0.9%. The second pair of reflection spectrum parameters of the CFBG (proposed in our previous work [14]) which represented by LRW and SRW are illustrated in Figure 4(c) and (d). As we can see from both responses, the data points are exhibited consistency and highly correlated for both procedures.…”

Digital Filtering Techniques for Performance Improvement of Golay Coded TDM-FBG Sensor

“…Both the grating period and the refractive index are sensitive to the strain or temperature induced by a local physical source; the shift in the Bragg wavelength can be illustrated as in [ 1 , 2 ]: where and are the changes in the temperature and strain, is the fiber thermal expansion factor and is the thermo-optic coefficient, and is the fiber material photoelastic coefficient [ 1 , 2 , 17 ]. Interrogating the FBG sensors in the time domain is possible by translating the shift in the Bragg wavelength induced by a physical impact into power variation that appears in the peak amplitude of the reflected FBG signals [ 5 ].…”

Design of Flow Velocity and Direction Monitoring Sensor Based on Fiber Bragg Grating

“…The lower part is mainly composed of a cardan plate and a steering shaft. As shown in Figure 1, the components of the sensor are listed as follows: (1) venturi, (2) sliding connection, (3) eccentric wheel, (4) washer, (5) closed push rod, (6) displacement conduction shaft, (7) displacement top shaft, (8) strain grating, (9) wire, (10) nut, (11) steering shaft, (12) simple beam, (13) support frame, (14) frame base, (15) rolling bearing, (16) coding plate of shaft sleeve, (17) water turbine, (18) lever, (19) universal plate, (20) coding plate of shaft sleeve and (21) optical fiber Grating.…”

“…In recent years, Fiber Bragg Grating (FBG) has been gradually used as a measuring element of various sensors because of its advantages such as being not easily interfered with by the external electromagnetic environment [ 12 , 13 ], high measurement accuracy [ 14 , 15 ], small volume, good wavelength selectivity [ 16 ], and not being affected by nonlinear effects. However, considering the fiber Bragg grating sensing technology, most scholars still study the flow velocity monitoring of directional fluid [ 17 ].…”