# A Low-Frequency Fiber Bragg Grating Acceleration Sensor Based on Spring Support and Symmetric Compensation Structure with Flexible Hinges

## TL;DR

A new low-frequency acceleration sensor using fiber Bragg grating is designed and tested for measuring vibrations.

## Contribution

A novel FBG acceleration sensor with a symmetric compensation structure and flexible hinges is developed for low-frequency vibration measurement.

## Key findings

- The sensor has a resonant frequency of 73 Hz and an operating range of 0~60 Hz.
- The sensitivity of the sensor is measured at 24.24 pm/g.
- The design effectively meets low-frequency vibration measurement requirements.

## Abstract

To measure vibration signals, a low-frequency fiber Bragg grating (FBG) acceleration sensor featuring a flexible hinge with a spring support and symmetric compensation structure has been designed. Based on the mechanical model of the sensor’s structure, the expressions for sensitivity and resonant frequency of the sensor are derived. The structural parameters of the sensor are optimized, and a simulation analysis is conducted using ANSYS 19.2 software. According to the results of simulation analysis and size optimization, the sensor prototype is constructed. Subsequently, its amplitude-frequency response, sensitivity, and temperature characteristics are investigated through vibration experiments. The experimental results show that the resonant frequency of the sensor is 73 Hz, the operating frequency range is 0~60 Hz, and the sensitivity measures 24.24 pm/g. This design meets the requirements for measuring vibration signals at low frequencies.