Design and Fabrication of Liquid Pressure Sensor Using FBG Sensor Through Seesaw Hinge Mechanism

Abstract

Pressure sensors are used in various industrial applications assisting in preventing unintended disasters. This paper presents the design and fabrication of a novel Seesaw device incorporating a diaphragm and Fiber Bragg Grating (FBG) sensor to measure the pressure of liquids. The designed sensor has been tested in a static water column. The proposed design enables the user to easily make and modify the diaphragm based on the required pressure range without interfering with the FBG sensor. The developed pressure sensor produces improved accuracy and sensitivity to applied liquid pressure in both low and high-pressure ranges without requiring sophisticated sensor construction. A finite element analysis has been performed on the diaphragm and on the entire structure at 10 bar pressure. The deformation of the diaphragm is comparable to theoretical deformation levels. A copper diaphragm with a thickness of 0.25 mm is used in the experiments. All experiments are performed in the elastic region of the diaphragm. The sensor's sensitivity as 19.244 nm/MPa with the linearity of 99.64% is obtained based on the experiments. Also, the proposed sensor's performance is compared with recently reported pressure sensors.

Spectral power stabilization against temperature variations in multimode fiber Bragg gratings

“…In fact, various types of FBGs, such as regenerated FBGs, 10,11) microstructure FBGs, 12) and tilted FBGs, 13) have been developed for hightemperature, refractive index, strain, pressure, acoustic wave, and other applications. [14][15][16][17] When fiber gratings are inscribed in single-mode fibers (SMFs), they reflect only a single wavelength of light, known as the Bragg wavelength λ = 2 • n eff • Λ, where n eff represents the effective refractive index of the fiber core and Λ denotes the grating pitch. In contrast, when FBGs are inscribed in multimode fibers (MMFs), they exhibit multiple reflection peaks around the fundamental Bragg peak due to the coupling between different linearly polarized (LP) modes.…”