A Sensitive Fiber Bragg Grating Strain Sensor Based on Micro-displacement Amplifying Mechanism

Abstract

The invention discloses a sensitivity-enhanced type fiber bragg grating strain sensor based on a micrometric displacement amplifying mechanism, and belongs to a fiber bragg grating sensor technology.The problems that an ordinary fiber bragg grating strain sensor is not high in sensitivity and the micro-strain of the structure cannot be accurately measured are solved. The sensitivity-enhanced typefiber bragg grating strain sensor comprises an upper layer protection shell, a sensitivity-enhanced amplifying mechanism, a bottom layer protection shell and a fiber bragg grating. Two connecting bosses of the sensitivity-enhanced amplifying mechanism can be connected with a measured object through rectangular holes in the bottom layer protection shell. The sensitivity-enhanced amplifying mechanism is further provided with a first-stage level and a second-stage level. The micrometric displacement generated by the measured object is subjected to two-stage amplifying and transmitted to the fiber bragg grating in a bragg grating installation groove. The sensor is remarkable in sensitivity enhancing effect, wide in use range and suitable for measuring the micro-strain of the structure.

Description

technical field [0001] The invention belongs to the technical field of optical fiber grating sensors, and relates to an enhanced-sensitivity optical fiber grating strain sensor, in particular to an enhanced-sensitivity optical fiber grating strain sensor based on a micro-displacement amplification mechanism. Background technique [0002] For the measurement of some micro-strains, the strain sensors used need to achieve high enough sensitivity, and ordinary fiber grating strain measurement sensors do not have sufficient sensitivity, so they are no longer suitable for micro-strain measurements of structures. At present, many fiber Bragg grating strain sensors use sensitizing materials to improve sensitivity, but the maximum sensitizing factor is about 5 times. This method has poor sensitivity improvement ability for strain sensors and requires high sensitizing materials. [0003] In order to improve the sensitivity, a substrate-type optical fiber grating strain sensor sensitiv...

AI Technical Summary

Problems solved by technology

At present, many fiber grating strain sensors use sensitizing materials to improve sensitivity, but the maximum sensitization multiple is about 5 times. This method has poor sensitivity improvement ability for strain sensors and requires high sensitizing materials.

[0003] In order to improve the sensitivity, a substrate-type FBG strain sensor sensitization structure has appeared in the prior art, but the volume of the FBG strain sensor with this sensitization structure is too large

In the prior art, there is also a fiber grating strain sensor packaged in a titanium alloy substrate, but the sensitivity improvement effect of the sensor with this sensitization structure is not significant

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