Dynamic-strain measurement with dual-grating fiber sensor

Area of Science:

• Optical Engineering
• Materials Science
• Metrology

Background:

• Accurate strain measurement is crucial for structural health monitoring and material analysis.
• Existing methods often struggle with temperature-induced errors and dynamic strain detection.
• Developing robust sensors for dynamic strain perturbations is an ongoing challenge.

Purpose of the Study:

• To develop and validate a dual-grating sensor head for temperature-insensitive strain measurement.
• To assess the sensor's capability in measuring fast-varying strain perturbations.
• To demonstrate the feasibility of dynamic strain measurement using a static strain configuration.

Main Methods:

• Utilized a dual-grating sensor head designed for temperature insensitivity.
• Employed a Mach-Zehnder interferometer technique for high-resolution measurements.
• Applied a 200-Hz dynamic strain input to test sensor performance.

Main Results:

• Achieved a root-mean-square (rms) resolution of approximately 0.1 microstrain (µε).
• Successfully measured fast-varying strain perturbations with high accuracy.
• Demonstrated the sensor's capability to measure dynamic strain within a static strain measurement setup.

Conclusions:

• The dual-grating sensor head offers a viable solution for precise, temperature-insensitive strain monitoring.
• The Mach-Zehnder interferometer technique enables high-resolution dynamic strain measurement.
• This technology holds potential for advanced applications in structural monitoring and material science.