Zufferey R, Ancel A Ortega, Farinha A, Siddall R, Armanini S F, Nasr M, Brahmal R V, Kennedy G, Kovac M
Aerial Robotics Lab, Imperial College of London, London, UK.
Materials and Technology Centre of Robotics, Swiss Federal Laboratories for Materials Science and Technology, Dübendorf, Switzerland.
Sci Robot. 2019 Sep 11;4(34). doi: 10.1126/scirobotics.aax7330.
Robotic vehicles that are capable of autonomously transitioning between various terrains and fluids have received notable attention in the past decade due to their potential to navigate previously unexplored and/or unpredictable environments. Specifically, aerial-aquatic mobility will enable robots to operate in cluttered aquatic environments and carry out a variety of sensing tasks. One of the principal challenges in the development of such vehicles is that the transition from water to flight is a power-intensive process. At a small scale, this is made more difficult by the limitations of electromechanical actuation and the unfavorable scaling of the physics involved. This paper investigates the use of solid reactants as a combustion gas source for consecutive aquatic jump-gliding sequences. We present an untethered robot that is capable of multiple launches from the water surface and of transitioning from jetting to a glide. The power required for aquatic jump-gliding is obtained by reacting calcium carbide powder with the available environmental water to produce combustible acetylene gas, allowing the robot to rapidly reach flight speed from water. The 160-gram robot could achieve a flight distance of 26 meters using 0.2 gram of calcium carbide. Here, the combustion process, jetting phase, and glide were modeled numerically and compared with experimental results. Combustion pressure and inertial measurements were collected on board during flight, and the vehicle trajectory and speed were analyzed using external tracking data. The proposed propulsion approach offers a promising solution for future high-power density aerial-aquatic propulsion in robotics.
在过去十年中，能够在各种地形和流体之间自主转换的机器人车辆因其在探索以前未开发和/或不可预测环境中的导航潜力而受到显著关注。具体而言，空中-水上机动性将使机器人能够在杂乱的水生环境中运行并执行各种传感任务。开发此类车辆的主要挑战之一是从水到飞行的转换是一个耗能密集的过程。在小尺度下，机电驱动的局限性以及相关物理过程的不利缩放使得这一过程更加困难。本文研究了使用固体反应物作为连续水上跳跃-滑翔序列的燃烧气体源。我们展示了一种无需系绳的机器人，它能够从水面进行多次发射，并从喷射过渡到滑翔。水上跳跃-滑翔所需的动力通过使碳化钙粉末与环境中的水反应产生可燃的乙炔气体来获得，从而使机器人能够从水中迅速达到飞行速度。这个160克的机器人使用0.2克碳化钙能够实现26米的飞行距离。在此，对燃烧过程、喷射阶段和滑翔进行了数值建模，并与实验结果进行了比较。在飞行过程中收集了燃烧压力和惯性测量数据，并使用外部跟踪数据对车辆轨迹和速度进行了分析。所提出的推进方法为未来机器人领域的高功率密度空中-水上推进提供了一个有前景的解决方案。
