Temperature self-compensation fiber grating displacement sensor

Abstract

The invention provides a temperature self-compensation fiber grating displacement sensor which has a structure that two bare fiber gratings which are encapsulated by capillary metal tubes are connected with a probe through a metal connecting block, a spring and a centre rod to form a main body of the temperature self-compensation fiber grating displacement sensor to execute functions; then the main body is arranged in a metal box; finally, the end parts of the capillary metal tubes are fixed with the metal box through the metal connecting block, fibers penetrate out from small holes positioned on the metal connecting block and the lateral wall of the metal box, and the probe can freely stretch through a guide rod hole of the metal box. When a displacement sensor is arranged on the structure, the probe and the metal box relatively move to enable the bare fiber gratings to extend or shorten so as to generate the drift of the operating wavelength of the bare fiber gratings when the structure generates displacement, and the displacement and the temperature of the structure can be tested by utilizing a temperature compensation principle and a displacement computing formula of the displacement sensor.

Description

technical field [0001] The invention relates to a displacement measuring device, in particular to a sensor for measuring the displacement of civil engineering structure model tests and long-term use. Background technique [0002] At present, ordinary electrical and vibrating wire displacement sensors are installed on the structure, which can measure the displacement of the structure under various loads in the short term or in the long term, so as to analyze the force status of the structure. However, this type of displacement sensor still has certain limitations in engineering applications. For example, the electrical displacement sensor is susceptible to electromagnetic interference, the measurement signal is unstable, and the vibrating wire displacement sensor will produce creep and poor long-term stability when used for a long time. [0003] In order to develop a displacement sensor with better performance for the state measurement of the structure, it is one of the effec...

AI Technical Summary

Problems solved by technology

However, this type of displacement sensor still has certain limitations in engineering applications. For example, the electrical displacement sensor is susceptible to electromagnetic interference, the measurement signal is unstable, and the vibrating wire displacement sensor will produce creep and poor long-term stability when used for a long time.

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