High-resolution fiber grating pressure sensor with in-situ calibration for deep sea exploration

Abstract

A high-resolution and wide-range pressure sensor based on π phase-shifted fiber Bragg grating (π-FBG) encapsulated with metal thin-walled cylinder is reported. The sensor has been tested with a wavelength-sweeping distributed feedback laser, photodetector and a H13C14N gas cell. To perceive temperature and pressure synchronously, a pair of π-FBGs are glued on the outer wall of the thin-walled cylinder along the circumferential direction with different angles. The interference of temperature is effectively corrected by a high-precision calibration algorithm. The reported sensor has a sensitivity of 4.42 pm/MPa, a resolution of 0.036% full scale (F.S.), and a repeatability error of 0.045% F.S. in the range of 0-110 MPa that corresponds to an ocean depth resolution of 5 m and a measurement range of eleven thousand meters to cover the deepest trench of the Ocean. The sensor features simplicity, good repeatability, and practicability.

Probe-Type Multi-Core Fiber Optic Sensor for Simultaneous Measurement of Seawater Salinity, Pressure, and Temperature

“…Numerous institutions and scholars have conducted research on optical fiber sensors for the measurement of salinity, temperature, and pressure [ 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 ]. For instance, L. Ji et al [ 17 ] introduced a π phase-shifted FBG sensor enclosed in a metal thin-walled cylinder, enabling the extensive range and high-resolution measurement of seawater pressure. D. Xue et al [ 18 ] combined microelectromechanical systems (MEMSs) with FPI interferometers to propose a highly sensitive fiber optic sensor that can simultaneously measure seawater salinity and temperature.…”

Research on an optical fiber sensor for real-time monitoring of gas pressure inside lithium batteries

“…Therefore, people need to detect the internal pressure of the battery. This is of great significance for understanding battery side reactions, health status, state of charge, leakage problems, etc [3] . Optical fiber has the characteristics of high temperature resistance, high pressure resistance, corrosion resistance, and resistance to electromagnetic interference.…”