A FBG two-dimensional acceleration sensor based on U-shaped groove structure and its measurement method

Abstract

The invention provides a FBG two-dimensional acceleration sensor based on a U-shaped groove structure and a measurement method thereof, which includes an upper shell and a lower shell, a core body located in the middle of the upper and lower shells, a number of optical fibers, and a grating. The upper inertial body, the middle body and the lower base are sequentially connected. The middle body of the core body is provided with two pairs of U-shaped groove structures facing away from each other. The axial position of the groove is provided with a vertically arranged square through hole, and four optical fiber grooves are evenly opened on the outer surface of the inertial body and the base. The four optical fibers are installed in the optical fiber grooves by applying a certain prestress. There are gratings engraved in the optical fiber, and the four gratings are adjacent to each other in two vertical directions, which is convenient for detecting vibration in two vertical directions. The sensor has the advantages of temperature compensation, accurate measurement of combined acceleration, anti-electromagnetic interference, simple structure, small size, and distributed measurement.

Description

technical field [0001] The invention belongs to the technical field of mechanical vibration measurement, and in particular relates to an FBG (Fiber Bragg Grating) two-dimensional acceleration sensor based on a U-shaped groove structure and a measurement method thereof. Background technique [0002] Fiber Bragg Grating sensors have attracted widespread attention due to their remarkable advantages, such as light and safe, anti-electromagnetic interference, corrosion resistance, and long-distance measurement. The existing fiber grating two-dimensional vibration acceleration sensors mainly include the following two types. One is the acceleration sensor with a structure such as an elastic beam. The measurement is not accurate enough; the second is the acceleration sensor made directly by using fiber grating as the elastic element. Although this type of acceleration sensor is simple in structure and small in size, the working frequency range and sensitivity of the two measurement ...

AI Technical Summary

Problems solved by technology

The existing fiber grating two-dimensional vibration acceleration sensors mainly include the following two types. One is the acceleration sensor with a structure such as an elastic beam. The measurement is not accurate enough; the second is the acceleration sensor made directly by using fiber grating as the elastic element. Although this type of acceleration sensor is simple in structure and small in size, the working frequency range and sensitivity of the two measurement directions are quite different, and the optical fiber itself is relatively fragile. , easily damaged, resulting in poor repeatability of such sensors

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