Extremely small deformation calibration method based on FBG sensor

Abstract

The invention discloses an extremely small deformation calibration method based on an FBG sensor, and aims to calibrate the deformation of a structural body under stress so as to detect the deformation of the structural body. The method comprises the following steps of laying fiber grating strain sensors on the structural body in a distributed manner to measure the deformation of a structural member, fixing one end of a to-be-measured member, enabling the other end of the to-be-measured member to be a free end, applying a force to the free end of the to-be-measured member by using a push-pull dynamometer clamp, and observing the displacement of the free end measured by a laser micrometer after the force is applied by the clamp, and controlling the to-be-measured member to generate the deformation with a fixed step length, and calibrating the data measured by the fiber grating strain sensors by taking the horizontal displacement at the free end of the to-be-measured member measured by the laser micrometer as a true value of deformation. According to the invention, the distributed fiber grating monitoring data of the deformation of the structural member can be calibrated, extremely-small deformation calibration of the structural member is realized, and the method can be used for the detection of the extremely-small deformation of the distributed fibers. The calibration method has the advantages of being easy to operate, high in detection precision, good in reliability and capable of working stably for a long time.

Description

technical field [0001] The invention relates to a very small deformation calibration method based on an FBG sensor, and belongs to the technical field of sensor calibration. Background technique [0002] As the society has higher and higher requirements for the accuracy of measurement technology. Micro deformation is a major focus of attention in today's world. Accurately obtaining the micro-deformation of components under external environmental factors is of great significance in basic scientific research, practical application, and technological innovation. [0003] The deformation sensor is a sensor that can directly or indirectly detect the deformation information of an object in time, transmit the information to the controller or directly alarm, and provide a basis for monitoring the deformation of structural parts and taking corresponding measures in time to control the attitude of structural parts. At present, there are many kinds of deformation sensors, among which...

AI Technical Summary

Problems solved by technology

Among them, the application of electrical sensor measurement is mature, but it is only suitable for small-scale networking. When large-scale networking will bring troubles such as an increase in the number of cables, the optical micrometer has requirements for the measurement range, and the measuring instrument is heavy and needs to be fixed. In the vicinity of the structure to be measured, high requirements are placed on the measurement environment. The development of photogrammetry is not mature enough, and the measurement accuracy cannot meet the required accuracy of small deformation detection.

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