Chen Di, Wu Zhengxing, Dong Huijie, Meng Yan, Yu Junzhi
State Key Laboratory for Turbulence and Complex Systems, Department of Advanced Manufacturing and Robotics, College of Engineering, Peking University, Beijing 100871, People's Republic of China.
State Key Laboratory of Management and Control for Complex Systems, Institute of Automation, Chinese Academy of Sciences, Beijing 100190, People's Republic of China.
Bioinspir Biomim. 2023 Apr 28;18(3). doi: 10.1088/1748-3190/acce86.
The aquatic-aerial robot with the free interface crossing can enhance adaptability in complex aquatic environments. However, its design is extremely challenging for the striking discrepancies in propulsion principles. The flying fish in nature exhibits remarkable multi-modal cross-domain locomotion capability, such as high-maneuvers swimming, agile water-air crossing, and long-distance gliding, providing extensive inspiration. In this paper, we present a unique aquatic-aerial robotic flying fish with powerful propulsion and a pair of morphing wing-like pectoral fins to realize cross-domain motion. Furthermore, to explore the gliding mechanism of flying fish, a dynamic model with a morphing structure of pectoral fins is established, and a double deep Q-network-based control strategy is proposed to optimize the gliding distance. Finally, experiments were conducted to analyze the locomotion of the robotic flying fish. The results suggest that the robotic flying fish can successfully perform the 'fish leaping and wing spreading' cross-domain locomotion with an exiting speed of 1.55 m s(5.9 body lengths per second, BL/s) and a crossing time of 0.233 s indicating its great potential in cross-domain. Simulation results have validated the effectiveness of the proposed control strategy and indicated that the dynamical adjustment of morphing pectoral fins contributes to improving the gliding distance. The maximum gliding distance has increased by 7.2%. This study will offer some significant insights into the system design and performance optimization of aquatic-aerial robots.
具有自由界面穿越功能的水空机器人能够增强在复杂水生环境中的适应性。然而，由于推进原理存在显著差异，其设计极具挑战性。自然界中的飞鱼展现出卓越的多模态跨域运动能力，如高机动性游泳、敏捷的水空穿越以及远距离滑翔，这提供了广泛的灵感。在本文中，我们提出了一种独特的水空机器人飞鱼，它具有强大的推进力和一对可变形的翼状胸鳍，以实现跨域运动。此外，为了探究飞鱼的滑翔机制，建立了一个具有胸鳍变形结构的动力学模型，并提出了一种基于双深度Q网络的控制策略来优化滑翔距离。最后，进行了实验以分析机器人飞鱼的运动。结果表明，机器人飞鱼能够成功地以1.55米/秒（每秒5.9个体长，BL/s）的出水速度和0.233秒的穿越时间执行“鱼跃展翼”跨域运动，这表明其在跨域方面具有巨大潜力。仿真结果验证了所提出控制策略的有效性，并表明胸鳍的动态变形有助于增加滑翔距离。最大滑翔距离增加了7.2%。这项研究将为水空机器人的系统设计和性能优化提供一些重要的见解。
