Optical fiber grating strain sensor calibration and wear detection system

Abstract

The present invention provides an optical fiber grating strain sensor calibration and wear life detection method, including the steps: a) building a testing system in which a broadband light source, an optical circulator, an optical fiber grating demodulation instrument, a single mode fiber, a Bragg optical fiber grating sensor, an optical fiber, a resistance strain gauge, a fixture, a constant strength cantilever beam and a strain acquisition device are connected in sequence; b) exerting loads on the constant strength cantilever beam through a linear actuator to subject the constant strength cantilever beam to produce strain; c) through the resistance strain gauge, acquiring the magnitude of the resistance change of the strain gauge; d) through the optical fiber grating demodulation instrument, accessing the peak translation of the reflected light of the Bragg optical fiber grating sensor generated by the strain caused by the constant strength cantilever beam; and e) calculating the relationship between the strain of the cantilever beam and the peak translation of the reflected light of the Bragg optical fiber grating sensor to realize the calibration and wear detection of the Bragg optical fiber grating sensor.

Description

technical field [0001] The invention relates to a fiber grating strain sensor calibration and fatigue detection system. Background technique [0002] Fiber Bragg grating is a kind of fiber optic passive device with milestone significance. Because of its unique advantages such as anti-electromagnetic interference, corrosion resistance, high insulation, wide range of measurement parameters, easy multiplexing and networking, and miniaturization, it has developed very rapidly. It has obtained important applications in the fields of electronic information, aerospace, materials and chemicals, construction and environment, underground pipe network, energy, military defense and so on. [0003] In the field of structural health monitoring, fiber grating sensors are widely used in the monitoring of strain parameters. At present, the metal packaged fiber grating sensor is usually pasted or welded on the surface of the structure, or the fiber grating is directly embedded in the composi...

AI Technical Summary

Problems solved by technology

However, at present, the strain measurement sensitivity of these two methods can only be based on the coefficient or theoretical value provided by the supplier, which is a general coefficient and has low accuracy.

[0004] So far, there is no reliable and accurate calibration method for the calibration of optical grating strain sensor sensitivity, and precise sensitivity is an important parameter to ensure the accuracy and repeatability of measurement results

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