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arXiv · 2310.11792

Real-time Perceptive Motion Control using Control Barrier Functions with Analytical Smoothing for Six-Wheeled-Telescopic-Legged Robot Tachyon 3

Noriaki Takasugi·Masaya Kinoshita·Yasuhisa Kamikawa·Ryoichi Tsuzaki·Atsushi Sakamoto·Toshimitsu Kai·Yasunori Kawanami
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Abstract

To achieve safe legged locomotion, it is important to generate motion in real-time considering various constraints in robots and environments. In this study, we propose a lightweight real-time perspective motion control system for the newly developed six-wheeled-telescopic-legged robot, Tachyon 3. In the proposed method, analytically smoothed constraints including Smooth Separating Axis Theorem (Smooth SAT) as a novel higher order differentiable collision detection for 3D shapes is applied to the Control Barrier Function (CBF). The proposed system integrating the CBF achieves online motion generation in a short control cycle of 1 ms that satisfies joint limitations, environmental collision avoidance and safe convex foothold constraints. The efficiency of Smooth SAT is shown from the collision detection time of 1 us or less and the CBF constraint computation time for Tachyon3 of several us. Furthermore, the effectiveness of the proposed system is verified through the stair-climbing motion, integrating online recognition in a simulation and a real machine.

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Noriaki Takasugi, Masaya Kinoshita, Yasuhisa Kamikawa, Ryoichi Tsuzaki, Atsushi Sakamoto, Toshimitsu Kai, Yasunori Kawanami. 2023-10-18. Real-time Perceptive Motion Control using Control Barrier Functions with Analytical Smoothing for Six-Wheeled-Telescopic-Legged Robot Tachyon 3. https://arxiv.org/abs/2310.11792

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