A 3D FBG Accelerometer Based on Two Pairs of Flexible Hinges
Hui Wang, Bing Yan, Lei Liang
Abstract
A three-dimensional (3D) FBG accelerometer was proposed by installing three FBGs in an integrated oscillator structure which consists of two pairs of flexible hinges, a thin cylinder mass block and a base. The theoretical model of the proposed 3D accelerometer was established, and the dynamic response characteristics of the 3D accelerometer with optimal structural parameters were simulated using finite element software. Lots of sensing tests were finished and the sensing data showed that the sensitivities of the proposed 3D accelerometer in X-, Y-, and Z-directions are 108.7 pm/g, 144.2 pm/g, and 27.9 pm/g respectively, the working frequency range in X- and Y- directions are 40 – 300 Hz, and the acceleration amplitude range is 1 – 10 g. The proposed 3D accelerometer has the advantages of small size (28 mm <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\times38$ </tex-math></inline-formula> mm <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\times38$ </tex-math></inline-formula> mm), light weight (42 g), and simultaneous measurement of multi-dimensional acceleration.