A Compact Metal Bellows-Based Fiber Bragg Grating Accelerometer for Structural Health Monitoring

A compact metal bellows-based fiber Bragg grating accelerometer is proposed in this paper. The acceleration can be measured by monitoring the center wavelength shift of FBG, which we show is proportional to accelerometer. The experimental results indicate that the FBG accelerometer with a high sensitivity of 567.2pm/g shows a good linear response of the wavelength shifts versus applied acceleration. In addition, it provides a broad flat response over a vibration frequency ranging from 5 to 120Hz. The upper vibration frequency limit of measure is determined by mechanical resonance, and can be tuned by varying the weight of inertial mass. A series of table-shaking tests were conducted and showed good performance of a prototype FBG accelerometer.