Actuation space reduction to facilitate insightful shape matching in a novel reconfigurable tendon driven continuum manipulator

2026-04-14

AI Summary

This work addresses the challenges of excessive actuation dimensionality and complex shape control in reconfigurable tendon-driven continuum robots, which arise from tendon rerouting. To circumvent the need for intricate dynamic modeling, the authors propose an actuation space reduction method that maps the backbone configuration into an intermediate curvature–torsion space to identify critical actuation disks. By integrating a rerouting mechanism based on actively rotated spacer disks and employing a proximal-to-distal staged shape-matching strategy, the approach effectively approximates the global configuration while enabling fine distal adjustments. This methodology significantly enhances the intuitiveness and efficiency of shape control without relying on complex kinematic or dynamic models.

Technology Category

• Intelligent Robots: Manipulation
• Planning, Routing, and Scheduling: Replanning and Plan Repair
• Search and Optimization: Mixed Discrete/Continuous Search

Application Category

• Graph Algorithms and Modeling for the Web: Efficient manipulation of static and dynamic Web-related graphs
• Responsible Web: Machine-in-the-loop, human agency and autonomy
• User Modeling, Personalization and Recommendation: On-Device user modeling, personalization, and recommendation

Abstract

In tendon driven continuum manipulators (TDCMs), reconfiguring the tendon routing enables tailored spatial deformation of the backbone. This work presents a design in which tendons can be rerouted either prior to or after actuation by actively rotating the individual spacer disks. Each disk rotation thus adds a degree of freedom to the actuation space, complicating the mapping from a desired backbone curve to the corresponding actuator inputs. However, when the backbone shape is projected into an intermediate space defined by curvature and torsion (C-T), patterns emerge that highlight which disks are most influential in achieving a global shape. This insight enables a simplified, sequential shape-matching strategy: first, the proximal and intermediate disks are rotated to approximate the global shape; then, the distal disks are adjusted to fine-tune the end-effector position with minimal impact on the overall shape. The proposed actuation framework offers a model-free alternative to conventional control approaches, bypassing the complexities of modeling reconfigurable TDCMs.

Problem

• tendon-driven continuum manipulator
• actuation space
• shape matching
• reconfigurable mechanism
• backbone deformation

Innovation

• actuation space reduction
• reconfigurable tendon-driven continuum manipulator
• curvature-torsion space
• model-free control
• shape matching