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Updated: May 26, 2026
08:23
A Random-displacement Measurement by Combining a Magnetic Scale and Two Fiber Bragg Gratings
Published on: September 30, 2019
Error analysis and measurement uncertainty for a fiber grating strain-temperature sensor.
Jaw-Luen Tang1, Jian-Neng Wang
1Department of Physics, National Chung Cheng University, 168 University Road, Chia-Yi 62102, Taiwan. jawluen@phy.ccu.edu.tw
Sensors (Basel, Switzerland)
|December 14, 2011
Summary
This study presents a fiber Bragg grating sensor for distinguishing temperature and strain. It details error analysis and measurement uncertainty, achieving high accuracy for simultaneous sensing applications.
Area of Science:
- Optoelectronics
- Fiber optic sensing technology
- Metrology
Background:
- Accurate simultaneous measurement of temperature and strain is crucial in various engineering applications.
- Existing fiber optic sensors often face challenges in decoupling temperature and strain effects.
- Fiber Bragg gratings (FBGs) are widely used but require advanced methods for dual-parameter sensing.
Purpose of the Study:
- To develop and validate a fiber grating sensor system capable of distinguishing between temperature and strain.
- To conduct a thorough theoretical and experimental analysis of the sensor's error and measurement uncertainty.
- To establish a reliable method for quantifying uncertainty in simultaneous strain-temperature sensing using FBGs.
Main Methods:
- Utilized a dual-wavelength fiber Bragg grating sensor configuration with a reference grating.
- Performed theoretical calculations and experimental measurements to assess sensor performance.
- Analyzed root mean squared errors and maximum errors for both temperature and strain.
- Estimated expanded uncertainty at a 95% confidence level using a coverage factor.
Main Results:
- The sensor demonstrated the ability to distinguish between temperature and strain.
- Measured root mean squared errors were 0.13 °C for temperature and 6 με for strain.
- Maximum error calculations provided bounds for temperature and strain measurements.
- Evaluated temperature and strain measurement uncertainties as 2.60 °C and 32.05 με, respectively.
Conclusions:
- Successfully demonstrated a fiber grating sensor for simultaneous strain and temperature measurement.
- Provided a comprehensive analysis of measurement uncertainty for this sensing system.
- This work represents a significant advancement in the field of dual-parameter fiber optic sensing.
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