A Fiber Bragg Grating Array Strain Sensor with High Sensitivity, High Resolution and High Precision

Abstract

The invention relates to a high-sensitivity high-resolution high-precision fiber Bragg grating array strain sensor which comprises a force receiving system, a sensing system and a packaging system. In the force receiving system, the real gauge length between the two ends of a sensor substrate through fixing bolts is greater than the distance between grating welding spots. Displacement to be measured is exerted towards the outer side through the fixing bolts on the two ends. The sensor substrate further sends the displacement to an intersecting hollowed zone outer edge and further transmits the displacement to a central multi-fiber grating sensing system. In this way, strain sensing is achieved. The real gauge length is greater. The rigidity in the middle intersecting hollowed zone sharply decreases. The sensor substrate deformation mainly occurs on the middle intersecting hollowed zone. The sensing system adopts a multi-grating parallel arranging means to form arrays. During a deformation generation process, the change values of multiple grating wavelengths are measured and the average value is acquired. A sensitivity curve with enhanced sensitivity is converted into corresponding strain. Therefore, the design makes the sensor sensitivity, precision and resolution improved.

Description

technical field [0001] The invention relates to an optical fiber Bragg grating strain sensor suitable for on-site measurement of the surface strain of civil engineering structures such as bridge structures, towering structures, large-span space structures and cooling towers. Harsh environment capability test, large deformation monitoring technology field of structure surface. Background technique [0002] Strain sensing technology with high precision, high resolution and high sensitivity is required in the strain monitoring of existing bridges and building structures. For the traditional small-gauge fiber Bragg grating strain sensor, its sensitivity, resolution, and accuracy are not high, and the expected effect cannot be achieved. The existing long-gauge fiber Bragg grating strain sensor can improve the strain sensitivity to a certain extent, but Limited ability to improve accuracy. These conventional fiber grating sensors can improve their sensitivity, resolution, and pr...

AI Technical Summary

Problems solved by technology

At present, due to the huge time and cost, relatively high test cost and long working cycle, the accuracy of measured data also involves many factors such as sensor quality, data collection and transmission, information storage and post-processing, etc., full-scale large-scale There are not many studies on the actual measurement of surface deformation of space structures

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