For legged robots, aerial motions are the only option to overpass obstacles that cannot be circumvent with standard locomotion gaits. In these cases, the robot must perform a leap to either jump onto the obstacle or fly over it. However, these movements represent a challenge because during the flight phase the Center of Mass (CoM) cannot be controlled, and the robot orientation has limited controllability. This paper focuses on the latter issue and proposes an Orientation Control System (OCS) consisting of two rotating and actuated masses (flywheels or reaction wheels) to gain control authority on the robot orientation. Because of the conservation of angular momentum, their rotational velocity can be adjusted to steer the robot orientation even when there are no contacts with the ground. The axes of rotation of the flywheels are designed to be incident, leading to a compact orientation control system that is capable of controlling both roll and pitch angles, considering the different moment of inertia in the two directions. We tested the concept with simulations on the robot Solo12.

翻译：对于腿足式机器人而言，当障碍物无法通过标准步态绕行时，空中运动是跨越障碍的唯一选择。在此类场景中，机器人必须执行跳跃动作，以跃上障碍物或从其上方飞过。然而，这些运动极具挑战性，因为飞行阶段无法控制质心，且机器人姿态的可控性十分有限。本文聚焦于姿态可控性问题，提出一种由两个旋转驱动质量块（飞轮或反作用轮）构成的方向控制系统，以增强对机器人姿态的控制能力。基于角动量守恒原理，即使机器人未与地面接触，也可通过调节飞轮转速来改变其姿态。飞轮旋转轴被设计为共面相交，形成紧凑型方向控制系统，能够在两个方向转动惯量不同的情况下，同时控制俯仰角和横滚角。我们通过在Solo12机器人上进行的仿真实验验证了这一概念。