Optical fiber sensor capable of measuring stress direction

Abstract

The invention discloses an optical fiber sensor capable of measuring stress direction. The optical fiber sensor comprises a laser, a first polarization controller, a sensing fiber, a second polarization controller, a polarization analyzer and a computer Matlab algorithm, which are connected in sequence. When the sensing fiber is subjected to an external stress, the polarization analyzer records information of rotation of a polarization state around a principal axis of the external stress on a Poincare sphere; and the Matlab algorithm calculates an actual direction angle of the external stress based on linear relation between a direction angle of the external stress principal axis with respect to a reference external stress principal axis and the actual direction angle of the external stress.

Description

technical field [0001] The invention relates to the field of sensor technology, in particular to a principle based on the principle that the polarization state of an optical fiber rotates around the main axis of external stress on a Poincar sphere under the action of external stress, and is measured by the linear relationship between the main axis direction angle of the external stress and the actual direction angle of the external stress Fiber optic sensor for actual orientation angle of external stress. Background technique [0002] Compared with electrical sensors, fiber optic sensors have the advantages of high integration, strong anti-interference ability, low cost, high sensitivity and precision, good insulation, and distributed measurement. Therefore, fiber optic sensors have become a hot research field. Fiber optic sensors can be used to measure physical quantities such as stress, strain, vibration, temperature, displacement, sound, bending, and humidity. Optical fi...

AI Technical Summary

Problems solved by technology

However, these technologies are often limited to specific optical fibers, and have high requirements for detectors, which is not conducive to the reduction of costs and the promotion of practical applications; in addition, all current optical fiber stress sensors are limited to measuring the magnitude of stress and cannot achieve corresponding Measurement of Force Direction

The measurement of the stress direction is still limited to the use of traditional mechanical measurement, resulting in the disadvantages of large size, high price, low precision and low integration of the sensor.

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