Many real-world applications for robots—such as long-term aerial and underwater observation, cross-medium operations, and marine life surveys—require robots with the ability to move between the air-water boundary. Here, we describe an aerial-aquatic hitchhiking robot that is self-contained for flying, swimming, and attaching to surfaces in both air and water and that can seamlessly move between the two. We describe this robot’s redundant, hydrostatically enhanced hitchhiking device, inspired by the morphology of a remora ( Echeneis naucrates ) disc, which works in both air and water. As with the biological remora disc, this device has separate lamellar compartments for redundant sealing, which enables the robot to achieve adhesion and hitchhike with only partial disc attachment. The self-contained, rotor-based aerial-aquatic robot, which has passively morphing propellers that unfold in the air and fold underwater, can cross the air-water boundary in 0.35 second. The robot can perform rapid attachment and detachment on challenging surfaces both in air and under water, including curved, rough, incomplete, and biofouling surfaces, and achieve long-duration adhesion with minimal oscillation. We also show that the robot can attach to and hitchhike on moving surfaces. In field tests, we show that the robot can record video in both media and move objects across the air/water boundary in a mountain stream and the ocean. We envision that this study can pave the way for future robots with autonomous biological detection, monitoring, and tracking capabilities in a wide variety of aerial-aquatic environments.

中文翻译：

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能够跨越空气-水边界并在表面搭便车的空中水上机器人

机器人的许多实际应用——例如长期空中和水下观察、跨介质操作和海洋生物调查——需要机器人能够在空气-水边界之间移动。在这里，我们描述了一种空中水上搭便车机器人，它可以独立飞行、游泳和附着在空气和水中的表面上，并且可以在两者之间无缝移动。我们描述了这个机器人的冗余、流体静力增强的搭便车装置，灵感来自于 remora 的形态。刺棘鱼) 圆盘，可在空气和水中工作。与生物鲱鱼盘一样，该设备具有独立的层状隔间，用于冗余密封，使机器人仅通过部分盘附着即可实现粘附和搭便车。这种独立的、基于转子的空中水上机器人具有被动变形的螺旋桨，可在空中展开并在水下折叠，可以在 0.35 秒内穿越气水边界。该机器人可以在空气和水下的具有挑战性的表面上进行快速附着和分离，包括弯曲、粗糙、不完整和生物污染的表面，并以最小的振动实现长时间的粘附。我们还展示了机器人可以附着在移动的表面上并在其上搭便车。在现场测试中，我们展示了该机器人可以在两种媒体中录制视频，并可以在山涧和海洋中跨越空气/水边界移动物体。我们设想，这项研究可以为未来的机器人铺平道路，在各种空中-水生环境中具有自主生物检测、监测和跟踪能力。