Fiber Bragg Grating Low-frequency Accelerometer Design And Experimental Research

The low frequency vibration widely exists in mechanical device, in large-scale construction structure as well as processing process, because present mainly uses the electromagnetism class accelerometer to collect the low frequency vibration, as a result of electromagnetism class accelerometer natural existence's some insufficiencies, for instance the electromagnetic interference, to be corroded easily and so on, it affected the electromagnetism class accelerometer in these aspect application. Fiber Bragg grating sensor is one kind of optical fiber sensor who is extremely rapid developing at present, It is not subject to electromagnetic interference, not to be corroded easily, can achieve long-distance distributed measurement and so on. It just can make up for electromagnetic type sensor in the application, based on the FBG accelerometer is great project significance.In this paper, we design and manufacture a low-frequency fiber bragg grating accelerometer. Has carried on the theoretical analysis and the experimental study to this plan.Through the theoretical analysis, obtains this accelerometer wave length sensitivity is 36.2pm/g, because the optical fiber network analyzer's resolution is 1 pm, this accelerometer resolution is 0.028g, the natural frequency is 53.12Hz, the frequency response scope is 0-18 Hz.In order to confirm the design is Correct, this article to the low frequency fiber bragg grating accelerometer conducts the experimental study, the experiment has divided into the resistance strain accelerometer and fiber bragg grating accelerometer tests two parts, we carried on the cantilever beam fiber bragg grating accelerometer experiment first, The experiment demonstrates the fiber bragg grating accelerometer when it is not added in silicone oil damping the frequency sound scope is 0-11Hz, After joining the silicone oil damping, the experiment demonstrated that this frequency sound range extension 0-22Hz, The resistance strain accelerometer experiment demonstrated that has not added the silicone oil damping ,frequency sound scope is 0-12 Hz, after joining the silicone oil damping, the frequency sound scope is 0-20 Hz.Through the fiber bragg grating accelerometer and the resistance strain accelerometer's contrast test, the fiber bragg grating accelerometer frequency sound scope and the resistance strain accelerometer frequency sound scope tallies basically, and the very close theory frequency response scope, this contrast test experiment had demonstrated that our design is correct, has laid the foundation for the following work.