Battery endurance represents a key challenge for long-term autonomy and long-range operations, especially in the case of aerial robots. In this paper, we propose AutoCharge, an autonomous charging solution for quadrotors that combines a portable ground station with a flexible, lightweight charging tether and is capable of universal, highly efficient, and robust charging. We design and manufacture a pair of circular magnetic connectors to ensure a precise orientation-agnostic electrical connection between the ground station and the charging tether. Moreover, we supply the ground station with an electromagnet that largely increases the tolerance to localization and control errors during the docking maneuver, while still guaranteeing smooth un-docking once the charging process is completed. We demonstrate AutoCharge on a perpetual 10 hours quadrotor flight experiment and show that the docking and un-docking performance is solidly repeatable, enabling perpetual quadrotor flight missions.

翻译：电池续航能力是空中机器人在长期自主运行和远程作业中面临的关键挑战。本文提出AutoCharge——一种面向四旋翼飞行器的自主充电解决方案，该方案将便携式地面基站与灵活轻量化的充电连接装置相结合，可实现通用、高效且鲁棒性强的充电过程。我们设计并制造了一对圆形磁吸连接器，确保地面基站与充电装置间不受方向限制的精确电气连接。此外，我们在基站中配置电磁铁，该设计可大幅提升对接操作中对定位及控制误差的容错能力，同时保证充电完成后脱开过程的流畅性。通过持续10小时的四旋翼飞行实验，我们验证了AutoCharge的可行性，并表明其对接与脱开性能具备高度可重复性，从而支持四旋翼飞行器执行永续飞行任务。