An Optical Fiber Acceleration Sensor Based on a V-Shaped Flexure Hinge Structure
Thi Thuy-Vy Nguyen, Hoang-Dang Le, Hsiang-Cheng Hsu, Chi-Ngon Nguyen, Chia‐Chin Chiang
Abstract
This article proposes a novel vibration sensor based on fiber Bragg grating (FBG) technology. The sensor employs a V-shaped flexure hinge structure, which is theoretically and experimentally demonstrated to enhance sensitivity for vibration sensing. The proposed design utilizes the V-shaped flexures hinge to focus the acceleration-induced strain, resulting in improved performance for vibration sensitivity. The implementation of the FBG sensor was evaluated through theoretical computations using MATLAB. The simulation software was also used to simulate the proposed structure and assess the parameters affecting its sensing performance. The experimental results of this work sensor demonstrate a sensitivity of 79.46 pm/G and a resonant frequency of 1140 Hz. The sensor’s operating frequency bandwidth was 30–320 Hz, while the temperature influence was measured at 8.5 pm/°C. In addition, the amplitude in the transverse direction was only 3% of the amplitude in the working principle, indicating that the presented sensor has solid lateral immunity. The experimental results were consistent with the simulation findings, demonstrating the presented vibration sensor’s good performance. The given work provides an opportunity to apply the FBG acceleration sensor in the high-dependability detection of low- and medium-frequency vibration signals.