High-Quality Factor FBG-FPI Accelerometer With Adjustable Resonant Frequency and Sensitivity Using Additional Mass

We propose and demonstrate a spring-mass structure accelerometer based on a fiber Bragg grating Fabry-Perot interferometer (FBG-FPI). The sensitivity and resonant frequency of the accelerometer can be adjusted by adding an additional mass block. A theoretical model of the accelerometer was established and simulated using finite element analysis, with experimental verification of the theoretical formulas for its sensitivity and resonant frequency. Experimental results indicate that modifying the additional mass block allows adjustment of the accelerometer’s resonant frequency within the range of 720–1200 Hz, achieving a maximum sensitivity of 403.2 rad/g. To further validate the proposed method’s effectiveness, we conducted a comparative test between this accelerometer and a traditional electromagnetic one, confirming its performance and reliability in practical applications.