A new fiber Bragg grating accelerometer

A design method for a novel differential fiber Bragg grating (FBG) accelerometer is presented in this paper. The resonance frequency is increased via this sensing element design, which is combining the big beam and the two tiny beams. The differential double FBGs design increases the accelerometer sensitivity and resolves the temperature compensation. The mathematics model of the sensing element is established, the static and modal mechanics character is simulated by finite element method, the results indicate that the system sensitivity is 53.1pm/g and resonance frequency is 250Hz which is three times than that of the conventional cantilever-mass FBG accelerometer. The problem of being not able to increase the sensitivity and the resonance frequency simultaneously for the conventional FBG accelerometer has been resolved radically. Finally, the test system is set up, the testing data of the sensing element structure characteristic are acquired and analyzed.