Single-Fiber Optical Frequency Domain Reflectometry Shape Sensing of Continuum Manipulators with Planar Bending

TL;DR

This paper presents a novel single-fiber OFDR-based shape sensing method for continuum manipulators, achieving high accuracy in reconstructing complex shapes with a simple, easy-to-manufacture sensor attached to a soft, long manipulator.

Contribution

The study introduces a unique, single-fiber OFDR sensor attached to a flat nitinol wire for accurate shape sensing of continuum manipulators, simplifying fabrication and improving performance.

Findings

Achieved < 2 mm tip error in C-shape experiments

Achieved < 3.4 mm tip error in J-shape experiments

Demonstrated high shape reconstruction accuracy with a simple sensor design

Abstract

To address the challenges associated with shape sensing of continuum manipulators (CMs) using Fiber Bragg Grating (FBG) optical fibers, we feature a unique shape sensing assembly utilizing solely a single Optical Frequency Domain Reflectometry (OFDR) fiber attached to a flat nitinol wire (NiTi). Integrating this easy-to-manufacture unique sensor with a long and soft CM with 170 mm length, we performed different experiments to evaluate its shape reconstruction ability. Results demonstrate phenomenal shape reconstruction accuracy for both C-shape (< 2 mm tip error, < 1.2 mm shape error) and J-shape (< 3.4 mm tip error, < 2.3 mm shape error) experiments.