Orientation to Pose: Continuum Robots Shape Sensing Based on Piecewise Polynomial Curvature Model

TL;DR

This paper introduces a real-time shape sensing framework for continuum robots using piecewise polynomial curvature modeling and orientation sensors, enhancing accuracy and universality in control.

Contribution

It presents a novel shape sensing method based on PPC kinematics and orientation estimation, bridging orientation and position for continuum robots.

Findings

Framework verified on multiple prototypes

Achieved accurate shape estimation in real-time

Demonstrated universality across different robot types

Abstract

Continuum robots are typically slender and flexible with infinite freedoms in theory, which poses a challenge for their control and application. The shape sensing of continuum robots is vital to realise accuracy control. This letter proposed a novel general real-time shape sensing framework of continuum robots based on the piecewise polynomial curvature (PPC) kinematics model. We illustrate the coupling between orientation and position at any given location of the continuum robots. Further, the coupling relation could be bridged by the PPC kinematics. Therefore, we propose to estimate the shape of continuum robots through orientation estimation, using the off-the-shelf orientation sensors, e.g., IMUs, mounted on certain locations. The approach gives a valuable framework to the shape sensing of continuum robots, universality, accuracy and convenience. The accuracy of the general approach is verified in the experiments of multi-type physical prototypes.