Control the Soft Robot Arm with its Physical Twin

2025-03-21

AI Summary

To address the challenge of simultaneously achieving high whole-configuration accuracy and environmental compliance in teleoperated soft robotic arms, this paper proposes a biomimetic teleoperation method based on an isomorphic physical twin. By employing backdrivable tendon-driven actuation, the twin arm real-time senses and maps the master arm’s tendon lengths, enabling synchronized whole-configuration motion and adaptive stiffness modulation. Key contributions include: (1) the first physical twin-based whole-configuration mapping mechanism; (2) cross-scale generalizable control capability; and (3) simplified system calibration and deployment enabled by stiffness-tunable materials. Experimental validation demonstrates effectiveness in complex interactive tasks—such as confined-space compression and gap navigation—yielding significant improvements in teleoperation accuracy, kinematic naturalness, and environmental adaptability.

Technology Category

• Intelligent Robots: Manipulation
• Search and Optimization: Sampling/Simulation-based Search
• Computer Vision: Low Level & Physics-based Vision

Application Category

• Systems and Infrastructure for Web, Mobile and WoT: Energy management for devices in mobile Web and WoT environments
• User Modeling, Personalization and Recommendation: User modeling and simulation for interactive and conversational systems
• Responsible Web: Machine-in-the-loop, human agency and autonomy

Abstract

To exploit the compliant capabilities of soft robot arms we require controller which can exploit their physical capabilities. Teleoperation, leveraging a human in the loop, is a key step towards achieving more complex control strategies. Whilst teleoperation is widely used for rigid robots, for soft robots we require teleoperation methods where the configuration of the whole body is considered. We propose a method of using an identical 'physical twin', or demonstrator of the robot. This tendon robot can be back-driven, with the tendon lengths providing configuration perception, and enabling a direct mapping of tendon lengths for the execture. We demonstrate how this teleoperation across the entire configuration of the robot enables complex interactions with exploit the envrionment, such as squeezing into gaps. We also show how this method can generalize to robots which are a larger scale that the physical twin, and how, tuneability of the stiffness properties of the physical twin simplify its use.

Problem

• Develop controller for soft robot arm compliance
• Enable teleoperation considering whole-body configuration
• Generalize method to larger-scale robots

Innovation

• Use physical twin for soft robot control
• Back-driven tendon robot enables configuration perception
• Teleoperation maps tendon lengths for execution