A multi-cantilever beam low-frequency FBG acceleration sensor

Li Hong; Rui Sun; Zhongchao Qiu; Zhiming Han; Yanan Li

doi:10.1038/s41598-021-98055-z

A multi-cantilever beam low-frequency FBG acceleration sensor

Sci Rep. 2021 Sep 16;11(1):18502. doi: 10.1038/s41598-021-98055-z.

Authors

Li Hong^{1

2}, Rui Sun^{1

2}, Zhongchao Qiu^{3

4

5}, Zhiming Han^{1

2}, Yanan Li^{1

2}

Affiliations

¹ Institute of Disaster Prevention, School of Electronic Science and Control Engineering, Sanhe, 065201, Hebei, China.
² Key Laboratory of Seismic Dynamics of Hebei Province, Sanhe, 065201, Hebei, China.
³ Institute of Disaster Prevention, School of Electronic Science and Control Engineering, Sanhe, 065201, Hebei, China. [email protected].
⁴ Key Laboratory of Seismic Dynamics of Hebei Province, Sanhe, 065201, Hebei, China. [email protected].
⁵ Institute of Geophysics, China Earthquake Administration, Beijing, 100081, China. [email protected].

Abstract

The acquisition of 2-50 Hz low-frequency vibration signals is of great significance for the monitoring researches on engineering seismology, bridges & dams, oil & gas exploration, etc. A multi-cantilever beam low-frequency FBG acceleration sensor is proposed against the low sensitivity that predominates in the low-frequency vibration measurement by FBG acceleration sensors. Structural parameters of the sensor is subjected to simulation analysis and optimization design using the ANSYS software; the real sensor is developed based on the simulation results in the following manner: Three rectangular of the cantilever beams are evenly arranged around the mass block at 120°to improve the sensitivity and alleviate the transverse crosstalk of sensor; in the end, a performance test is performed on the sensor. According to the research findings, the sensor, whose natural frequency is approximately 64 Hz, is applicable for monitoring the low-frequency vibration signals within the range 16-54 Hz. The sensor sensitivity is approximately [Formula: see text], the linearity being greater than 99%, the transverse interference immunity being lower than 2.58%, and the dynamic range being up to 86 dB. The findings offer a reference for developing sensor of the same type and further improving the sensitivity of fiber optic acceleration sensor.