Simultaneous Vector Bend and Temperature Sensing Based on a Polymer and Silica Optical Fibre Grating Pair

Area of Science:

• Materials Science
• Optical Engineering
• Sensor Technology

Background:

• Optical fibre Bragg gratings (FBGs) are widely used as sensors.
• Polymer optical fibre Bragg gratings (POFBGs) offer potential advantages over traditional silica FBGs.
• Understanding their response to external stimuli like bending is crucial for sensor development.

Purpose of the Study:

• To compare the bending response of POFBGs and silica optical fibre Bragg gratings (SOFBGs).
• To propose a novel sensing method for simultaneous measurement of bend and temperature.
• To evaluate the performance of a hybrid sensor for combined vector bend and temperature sensing.

Main Methods:

• Systematic study and comparison of bending response for POFBG and SOFBG sensors mounted on a brass beam.
• Development of a hybrid sensor head by series connecting a POFBG and an SOFBG with distinct Bragg wavelengths.
• Experimental validation of the proposed method for simultaneous bend and temperature sensing.

Main Results:

• POFBG exhibits significantly higher bend sensitivity compared to SOFBG (nearly double).
• The proposed hybrid sensor successfully measures bend and temperature independently and simultaneously.
• The sensor demonstrates high sensitivity and resolution for both measured parameters.

Conclusions:

• POFBGs are more sensitive to bending than SOFBGs.
• A novel hybrid sensor utilizing POFBG and SOFBG enables simultaneous and independent measurement of bend and temperature.
• This technology is suitable for applications requiring high-precision sensing of both bend and temperature.