대형선박의 액체 탱크용 수위 모니터링 센서 시스템 연구

Abstract

Abstract ： A fiber-optic liquid level sensor based on bending cantilever b eam has been proposed. A fiber Bragg grating (FBG) embedded in the cantileve r beam is used to sensing elements. The basic concept is elongation and constrict ion of the FBG corresponding to the liquid level variation. The best FBG posit ion on the cantilever for obtaining the high sensitivity was 4 cm from the fixing point. When the liquid level moves up and down vertically, the Bragg wavelength is linearly shifted. But, the wavelength sensitivity of the FBG installed on the upper side of cantilever was four times better than that of the FBG equipped in the lateral side due to the difference of unit strain applied to the FBG. Intensity demodulation using th e low-cost edge filter is used to interrogate the Bragg wavelength through converting the wavelength signals into the optical intensity ones. Experiment results show that the electrical output is exponentially proportional to the liquid level. But, it should be overcome for applying to the ships.