A bioinspired wing generates lift that is robust to gusts and freestream turbulence without sacrificing flight duration. Small-scale drones have enough sensing and computing power to find use across a growing number of applications. However, flying in the low–Reynolds number regime remains challenging. High sensitivity to atmospheric turbulence compromises vehicle stability and control, and low aerodynamic efficiency limits flight duration. Conventional wing designs have thus far failed to address these two deficiencies simultaneously. Here, we draw inspiration from nature’s small flyers to design a wing with lift generation robust to gusts and freestream turbulence without sacrificing aerodynamic efficiency. This performance is achieved by forcing flow separation at the airfoil leading edge. Water and wind tunnel measurements are used to demonstrate the working principle and aerodynamic performance of the wing, showing a substantial reduction in the sensitivity of lift force production to freestream turbulence, as compared with the performance of an Eppler E423 low–Reynolds number wing. The minimum cruise power of a custom-built 104-gram fixed-wing drone equipped with the Separated Flow wing was measured in the wind tunnel indicating an upper limit for the flight time of 170 minutes, which is about four times higher than comparable existing fixed-wing drones. In addition, we present scaling guidelines and outline future design and manufacturing challenges.

中文翻译：

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受生物启发的分离式机翼可为微型无人机提供湍流回弹力和空气动力学效率

受生物启发的机翼产生的升力可抵抗阵风和自由流湍流，而不会牺牲飞行时间。小型无人机具有足够的传感和计算能力，可以在越来越多的应用程序中找到用途。但是，在低雷诺数系统中飞行仍然具有挑战性。对大气湍流的高灵敏度会损害飞行器的稳定性和控制能力，而低空气动力学效率会限制飞行时间。迄今为止，常规机翼设计未能同时解决这两个缺陷。在这里，我们从大自然的小传单中汲取灵感，设计出了一种机翼​​，该机翼具有强大的升力，能够抵抗阵风和自由流的湍流，而不会牺牲空气动力效率。通过强制翼型前缘处的气流分离来实现此性能。水和风洞测量被用来证明机翼的工作原理和空气动力性能，与Eppler E423低雷诺数机翼的性能相比，显着降低了升力产生对自由流湍流的敏感性。在风洞中测量了配备有分离流机翼的定制104克固定翼无人驾驶飞机的最小巡航功率，该飞行器指示飞行时间上限为170分钟，比现有的同类固定翼高约四倍。翼无人机。此外，我们提出了缩放准则，并概述了未来的设计和制造挑战。与Eppler E423低雷诺数翼的性能相比。在风洞中测量了配备有分离流机翼的定制104克固定翼无人驾驶飞机的最小巡航功率，该飞行器指示飞行时间上限为170分钟，比现有的同类固定翼高约四倍。翼无人机。此外，我们提出了缩放准则，并概述了未来的设计和制造挑战。与Eppler E423低雷诺数翼的性能相比。在风洞中测量了配备有分离流机翼的定制104克固定翼无人驾驶飞机的最小巡航功率，该飞行器指示飞行时间上限为170分钟，比现有的同类固定翼高约四倍。翼无人机。此外，我们提出了缩放准则，并概述了未来的设计和制造挑战。