大型段差昇り動作のための非線形軌道最適化：ヒューマノイドロボットAtlasへの応用
Non-Linear Trajectory Optimization for Large Step-Ups: Application to the Humanoid Robot Atlas
重心ダイナミクスの簡略モデルと足の接地切替を考慮した非線形軌道最適化で、ヒューマノイドの大きな段差昇り動作を生成し、Atlasで最大トルクを約20%削減できることを実機で示した。
著者: Stefano Dafarra, Sylvain Bertrand, Robert J. Griffin, Giorgio Metta, Daniele Pucci, Jerry Pratt
分類: cs.RO
原文アブストラクト
Performing large step-ups is a challenging task for a humanoid robot. It requires the robot to perform motions at the limit of its reachable workspace while straining to move its body upon the obstacle. This paper presents a non-linear trajectory optimization method for generating step-up motions. We adopt a simplified model of the centroidal dynamics to generate feasible Center of Mass trajectories aimed at reducing the torques required for the step-up motion. The activation and deactivation of contacts at both feet are considered explicitly. The output of the planner is a Center of Mass trajectory plus an optimal duration for each walking phase. These desired values are stabilized by a whole-body controller that determines a set of desired joint torques. We experimentally demonstrate that by using trajectory optimization techniques, the maximum torque required to the full-size humanoid robot Atlas can be reduced up to 20% when performing a step-up motion.
