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arXiv · 2411.13916

Joint-repositionable Inner-wireless Planar Snake Robot

Ayato Kanada·Ryo Takahashi·Keito Hayashi·Ryusuke Hosaka·Wakako Yukita·Yasutaka Nakashima·Tomoyuki Yokota·Takao Someya·Mitsuhiro Kamezaki·Yoshihiro Kawahara·Motoji Yamamoto
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Abstract

Bio-inspired multi-joint snake robots offer the advantages of terrain adaptability due to their limbless structure and high flexibility. However, a series of dozens of motor units in typical multiple-joint snake robots results in a heavy body structure and hundreds of watts of high power consumption. This paper presents a joint-repositionable, inner-wireless snake robot that enables multi-joint-like locomotion using a low-powered underactuated mechanism. The snake robot, consisting of a series of flexible passive links, can dynamically change its joint coupling configuration by repositioning motor-driven joint units along rack gears inside the robot. Additionally, a soft robot skin wirelessly powers the internal joint units, avoiding the risk of wire tangling and disconnection caused by the movable joint units. The combination of the joint-repositionable mechanism and the wireless-charging-enabled soft skin achieves a high degree of bending, along with a lightweight structure of 1.3 kg and energy-efficient wireless power transmission of 7.6 watts.

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Ayato Kanada, Ryo Takahashi, Keito Hayashi, Ryusuke Hosaka, Wakako Yukita, Yasutaka Nakashima, Tomoyuki Yokota, Takao Someya, Mitsuhiro Kamezaki, Yoshihiro Kawahara, Motoji Yamamoto. 2024-11-21. Joint-repositionable Inner-wireless Planar Snake Robot. https://doi.org/10.1109/lra.2025.3555394

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