車輪付き四脚ロボットの全身運動制御と計画
Keep Rollin' - Whole-Body Motion Control and Planning for Wheeled Quadrupedal Robots
車輪付き四脚ロボットの車輪自由度を統合したZMPベースの運動最適化と階層型全身制御器を開発し、段差や斜面を含む環境で歩行と走行を組み合わせた動的移動を実現した。
著者: Marko Bjelonic, C. Dario Bellicoso, Yvain de Viragh, Dhionis Sako, F. Dante Tresoldi, Fabian Jenelten, Marco Hutter
分類: cs.RO
原文アブストラクト
We show dynamic locomotion strategies for wheeled quadrupedal robots, which combine the advantages of both walking and driving. The developed optimization framework tightly integrates the additional degrees of freedom introduced by the wheels. Our approach relies on a zero-moment point based motion optimization which continuously updates reference trajectories. The reference motions are tracked by a hierarchical whole-body controller which computes optimal generalized accelerations and contact forces by solving a sequence of prioritized tasks including the nonholonomic rolling constraints. Our approach has been tested on ANYmal, a quadrupedal robot that is fully torque-controlled including the non-steerable wheels attached to its legs. We conducted experiments on flat and inclined terrains as well as over steps, whereby we show that integrating the wheels into the motion control and planning framework results in intuitive motion trajectories, which enable more robust and dynamic locomotion compared to other wheeled-legged robots. Moreover, with a speed of 4 m/s and a reduction of the cost of transport by 83 % we prove the superiority of wheeled-legged robots compared to their legged counterparts.
