A virtual-variable-length method for robust inverse kinematics of multi-segment continuum robots

Fuente: arXiv
Enregistré dans:
Détails bibliographiques
Auteurs principaux: Feng, Weiting, Renda, Federico, Yang, Yunjie, Giorgio-Serchi, Francesco
Format: Preprint
Publié: 2026
Sujets:
Accès en ligne:
Tags: Ajouter un tag
Pas de tags, Soyez le premier à ajouter un tag!
_version_ 1866908933754454016
author Feng, Weiting
Renda, Federico
Yang, Yunjie
Giorgio-Serchi, Francesco
author_facet Feng, Weiting
Renda, Federico
Yang, Yunjie
Giorgio-Serchi, Francesco
contents This paper proposes a new, robust method to solve the inverse kinematics (IK) of multi-segment continuum manipulators. Conventional Jacobian-based solvers, especially when initialized from neutral/rest configurations, often exhibit slow convergence and, in certain conditions, may fail to converge (deadlock). The Virtual-Variable-Length (VVL) method proposed here introduces fictitious variations of segments' length during the solution iteration, conferring virtual axial degrees of freedom that alleviate adverse behaviors and constraints, thus enabling or accelerating convergence. Comprehensive numerical experiments were conducted to compare the VVL method against benchmark Jacobian-based and Damped Least Square IK solvers. Across more than $1.8\times 10^6$ randomized trials covering manipulators with two to seven segments, the proposed approach achieved up to a 20$\%$ increase in convergence success rate over the benchmark and a 40-80$\%$ reduction in average iteration count under equivalent accuracy thresholds ($10^{-4}-10^{-8}$). While deadlocks are not restricted to workspace boundaries and may occur at arbitrary poses, our empirical study identifies boundary-proximal configurations as a frequent cause of failed convergence and the VVL method mitigates such occurrences over a statistical sample of test cases.
format Preprint
id arxiv_https___arxiv_org_abs_2604_02256
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle A virtual-variable-length method for robust inverse kinematics of multi-segment continuum robots
Feng, Weiting
Renda, Federico
Yang, Yunjie
Giorgio-Serchi, Francesco
Robotics
Numerical Analysis
Systems and Control
This paper proposes a new, robust method to solve the inverse kinematics (IK) of multi-segment continuum manipulators. Conventional Jacobian-based solvers, especially when initialized from neutral/rest configurations, often exhibit slow convergence and, in certain conditions, may fail to converge (deadlock). The Virtual-Variable-Length (VVL) method proposed here introduces fictitious variations of segments' length during the solution iteration, conferring virtual axial degrees of freedom that alleviate adverse behaviors and constraints, thus enabling or accelerating convergence. Comprehensive numerical experiments were conducted to compare the VVL method against benchmark Jacobian-based and Damped Least Square IK solvers. Across more than $1.8\times 10^6$ randomized trials covering manipulators with two to seven segments, the proposed approach achieved up to a 20$\%$ increase in convergence success rate over the benchmark and a 40-80$\%$ reduction in average iteration count under equivalent accuracy thresholds ($10^{-4}-10^{-8}$). While deadlocks are not restricted to workspace boundaries and may occur at arbitrary poses, our empirical study identifies boundary-proximal configurations as a frequent cause of failed convergence and the VVL method mitigates such occurrences over a statistical sample of test cases.
title A virtual-variable-length method for robust inverse kinematics of multi-segment continuum robots
topic Robotics
Numerical Analysis
Systems and Control
url https://arxiv.org/abs/2604.02256