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arXiv · 2503.17227

Control the Soft Robot Arm with its Physical Twin

Qinghua Guan·Hung Hon Cheng·Benhui Dai·Josie Hughes
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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.

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Qinghua Guan, Hung Hon Cheng, Benhui Dai, Josie Hughes. 2025-03-21. Control the Soft Robot Arm with its Physical Twin. https://arxiv.org/abs/2503.17227

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