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arXiv · 2606.19699

Comparative Study on Agility, Efficiency, and Impact Absorption of Bipedal Robots with Active Toes

Joong-Gil Kim·Wontae Ye·Geunwoo Cho·Seong-Ho Yun·Se-Hyoung Cho·Yong-Jae Kim
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Abstract

Human legs exhibit high efficiency, agility, and impact absorption, with toes playing a crucial role in these capabilities. While many attempts have been made to implement human-like toes in robots, they have not fully replicated human characteristics nor rigorously validated their benefits. We propose a 14-DOF biped robot emulating human toes' lightweight, high-torque, robust nature. To quantitatively analyze the effectiveness of the active toes in terms of agility, efficiency, and impact absorption, we developed a high-fidelity simulation training environment that reflects actual actuators with coupled transmissions and accurate power consumption. To ensure a fair comparison between configurations with and without active toes, we designed a minimal RL reward function and applied an identical training procedure to both. The simulation results indicate that, at 1.33 m/s walking, the toe-equipped robot reduced CoT by 17.5% and heel-strike GRF by 5.0% compared with the toe-ablation configuration. On the agility test, average and maximum path deviation decreased by 25.0% and 34.0%, respectively.

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Joong-Gil Kim, Wontae Ye, Geunwoo Cho, Seong-Ho Yun, Se-Hyoung Cho, Yong-Jae Kim. 2026-06-18. Comparative Study on Agility, Efficiency, and Impact Absorption of Bipedal Robots with Active Toes. https://arxiv.org/abs/2606.19699

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