FBG-Based Triaxial Force Sensor Integrated with an Eccentrically Configured Imaging Probe for Endoluminal Optical Biopsy

TL;DR

This paper presents a novel FBG-based triaxial force sensor integrated into an eccentric imaging probe for endoluminal optical biopsy, enhancing safety and precision in robotic bronchoscopy.

Contribution

It introduces a new force sensing approach with nonlinear decoupling and temperature compensation for improved accuracy in endoluminal interventions.

Findings

Achieved force measurement accuracy of 10.58 mN, 14.57 mN, and 26.32 mN along X, Y, Z axes.

Successfully demonstrated tissue testing to validate sensor feasibility.

Enabled flexible imaging probe with large eccentric lumen for optical biopsy.

Abstract

Accurate force sensing is important for endoluminal intervention in terms of both safety and lesion targeting. This paper develops an FBG-based force sensor for robotic bronchoscopy by configuring three FBG sensors at the lateral side of a conical substrate. It allows a large and eccentric inner lumen for the interventional instrument, enabling a flexible imaging probe inside to perform optical biopsy. The force sensor is embodied with a laser-profiled continuum robot and thermo drift is fully compensated by three temperature sensors integrated on the circumference surface of the sensor substrate. Different decoupling approaches are investigated, and nonlinear decoupling is adopted based on the cross-validation SVM and a Gaussian kernel function, achieving an accuracy of 10.58 mN, 14.57 mN and 26.32 mN along X, Y and Z axis, respectively. The tissue test is also investigated to further demonstrate the feasibility of the developed triaxial force sensor