Research on pasted FBG-based accelerometer’s sensitization process method and its characteristics

Abstract

A pasted FBG based cantilever beam accelerometer's sensitization process method has been proposed in this paper. We have built the pasted FBG-based cantilever beam accelerometer's sensitization process model. The sensor's sensitivity was improved by adjusting glue thickness between FBG and cantilever beam. Theoretical model has been proved by ANSYS simulation and experimental analysis: Simulation analysis shows that when distance between fiber core and cantilever beam is greater than 0.4 mm, it can be used to enhance sensitivity. Experimental analysis shows that when distance between fiber core and cantilever beam is 1 mm, sensitivity of sensor is increased by 2.9 times compared with the conventional process, but it has no effect on the sensor dynamic characteristics. Compared with conventional sensitization method, it's more general, and can be applied to all pasted FBG accelerometer for enhancing sensitivity.

Fiber Bragg grating based acceleration sensors: a review

“…Due to the structural characteristics of cantilever beam and simply supported beam, acceleration sensors fail to solve the problem that resonant frequency and sensitivity restrict each other seriously. For this reason, Wang et al (2011), Basumallick et al (2011), Basumallick et al (2013), Basumallick et al (2016), Basumallick et al (2020) and Guo et al (2013a, 2013b, 2013c), Li et al (2015a, 2015b, 2015c, 2015d) started with the vibration transfer efficiency to design a series of wavelength detecting FBG sensitized acceleration sensors. In 2011, Wang et al (2011) fixed the cantilever beam on a special triangle bracket to improve the efficiency of external vibration transmission.…”

“…Then the structure is shown in Figure 8(a). From 2013 to 2015, Guo et al (2013a, 2013b, 2013c) and Li et al (2015a, 2015b, 2015c, 2015d) designed two acceleration sensors with the same performance by adopting similar methods (Basumallick et al , 2011; Basumallick et al , 2013). In 2016, Basumallick et al (2016) used the Teflon patch and special weighted processing method to design a sensitized acceleration sensor with widened working frequency band.…”

“…Compared with common single-mode FBG, polymer FBG with higher sensitivity coefficient was implanted into the optimal position in the polyurethane layer away from the neutral layer of the cantilever beam, so that the sensor has better sensitivity while obtaining a wider working frequency band. The above sensors (Wang et al , 2011; Basumallick et al , 2011; Basumallick et al , 2013; Basumallick et al , 2016; Basumallick et al , 2020; Guo et al , 2013a, 2013b, 2013c; Li et al , 2015a, 2015b, 2015c, 2015d) are suitable for vibration measurement occasion where the high sensitivity is required, but they did not solve the problem of the temperature-strain cross-sensitivity.…”

“…The FBG between the mass block and the shell was subjected to the transverse force more sensitive than the axial force and the sensitivity of the sensor was improved. From 2013 to 2015, Li et al placed the mass block in which the cross-axis vibrations were limited in the middle of the fiber (Li et al , 2013) or connected the fiber with the transverse rod (Li et al , 2015a, 2015b, 2015c, 2015d) and made the FBG between the inertial object and the shell to design two-wavelength detecting FBG acceleration sensors with high sensitivity. Then one of these structures is shown in Figure 11(a).…”

“…Then one of these structures is shown in Figure 11(a). Instead of using common single-mode FBG (Talebinejad et al , 2009; Li et al , 2013; Li et al , 2015a, 2015b, 2015c, 2015d), Ni et al (2013) took the double-cone FBG as a sensing element and used an intensity detecting system to convert the wavelength drift into the light power variation and the value of the external acceleration could be measured by detecting the change of the light power in 2013 and the structure is shown in Figure 11(b). In the same year, Zhang et al (2013) directly etched a small mass block on a fiber with an etched FBG and a not etched FBG to design an intensity detecting FBG micro-sensor for simultaneous measurement of vibration and temperature.…”