Laboratory of Intelligent Systems, École Polytechnique Fédérale de Lausanne, Lausanne, Vaud, Switzerland.
School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore, Singapore, Singapore.
Nat Commun. 2024 Sep 27;15(1):8330. doi: 10.1038/s41467-024-52369-4.
Avian perching maneuvers are one of the most frequent and agile flight scenarios, where highly optimized flight trajectories, produced by rapid wing and tail morphing that generate high angular rates and accelerations, reduce kinetic energy at impact. While the behavioral, anatomical, and aerodynamic factors involved in these maneuvers are well described, the underlying control strategies are poorly understood. Here, we use optimal control methods on an avian-inspired drone with morphing wing and tail to test a recent hypothesis derived from perching maneuver experiments of Harris' hawks that birds minimize the distance flown at high angles of attack to dissipate kinetic energy before impact. The resulting drone flight trajectories, morphing sequence, and kinetic energy distribution resemble those measured in birds. Furthermore, experimental manipulation of the wings that would be difficult or unethical with animals reveals the morphing factors that are critical for optimal perching maneuver performance of birds and morphing-wing drones.
鸟类栖息动作是最常见和最敏捷的飞行场景之一，在这些动作中，通过快速的翅膀和尾巴变形产生的高度优化的飞行轨迹，产生高角速度和加速度，从而减少撞击时的动能。虽然这些动作涉及的行为、解剖和空气动力学因素已经得到很好的描述，但潜在的控制策略还知之甚少。在这里，我们使用变形翅膀和尾巴的鸟类启发式无人机上的最优控制方法来测试一个源自哈里斯鹰栖息动作实验的新假设，即鸟类在高攻角飞行时最小化飞行距离，以在撞击前耗散动能。得到的无人机飞行轨迹、变形序列和动能分布与鸟类测量的结果相似。此外，对翅膀的实验操作，这在动物身上可能是困难或不道德的，揭示了对于鸟类和变形翼无人机的最佳栖息动作性能至关重要的变形因素。
