A High-Frequency Acceleration Sensor Based on Fiber Grating

Fiber Bragg grating (FBG) acceleration sensor is an important branch of FBG application and has irreplaceable advantages compared with an electronic accelerometer. An FBG acceleration sensor with high sensitivity and high natural frequency is designed. This sensor adopts a double cantilever structure to sense the vibration perpendicular to the axis. Compared with a single cantilever structure, the natural frequency is increased without reducing the sensing length. Through the above structure design and material selection, the sensor shows a high natural frequency of 8658 Hz and its sensitivity is 0.44 pm/g. After the photoelectric demodulation is used, the sensitivity is 52 mV/g and the linearity is 0.998. Through the experiment and simulation analysis, the sensor performs good anti-interference in the transverse direction and temperature compensation in the process of vibration measurement. The system is very small due to the use of light intensity demodulation technology, which is conducive to application and integration in actual measurement scenarios.