Fiber Bragg grating accelerometer based on symmetrical double flexure hinges

A compact fiber Bragg grating (FBG) accelerometer based on symmetrical double flexure hinges structure is designed and demonstrated, which integrates the elastic elements and the inertial masses. The resonant frequency and sensitivity of the accelerometer are theoretically analyzed, and then the sensing performance of the accelerometer is researched through experiment. In the experiment, the wavelength shift of FBG shows a good linear response to external acceleration, the linearity is better than 99.6%. The measured resonant frequency of the accelerometer is about 890 Hz, and the sensitivity is about 41 pm/G. The experimental results are in good agreement with the theoretical values. The proposed accelerometer is capable of measuring the vibration acceleration in a wide range of 50-600 Hz, which makes the accelerometer have a good application prospect in the engineering fields.