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Simultaneous shape reconstruction and twist measurement based on optical frequency domain reflectometry.
Optics Express
|November 11, 2025
Summary
This study introduces a new fiber optic shape sensing method using optical frequency domain reflectometry (OFDR) to accurately measure both shape and twist in complex fiber optic cables. This advancement is crucial for precise robotic manipulation and medical surgery applications.
Area of Science:
- Optics
- Materials Science
- Robotics
Background:
- Fiber optic shape sensing (FOSS) is vital for applications like medical surgery and robotic manipulation.
- Accurate measurement of both shape and twist in FOSS is challenging but essential for advanced functionalities.
Purpose of the Study:
- To develop a method for simultaneous shape reconstruction and twist measurement in FOSS.
- To decouple bending and twist strains for improved accuracy in complex fiber shapes.
Main Methods:
- Utilized optical frequency domain reflectometry (OFDR) for simultaneous shape and twist measurement.
- Employed spun multiple single-core fibers (MFS) to separate bending and twist strains.
- Applied separated strain components for curvature estimation and twist angle measurement.
Main Results:
- Achieved accurate measurement of twist angles in 2D and 3D complex fiber shapes.
- Demonstrated improved orientation measurement accuracy in complex shape reconstruction.
- Reported a mean absolute error (MAE) of 3.787° for twist measurement and 0.896% MRE for Euclidean distance in shape reconstruction.
Conclusions:
- The proposed OFDR-based method successfully enables simultaneous shape reconstruction and twist measurement.
- This technique enhances positioning accuracy for applications requiring angular variation, such as medical and surgical robotics.
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