Investigation of flapping wings of insect are focused on low Reynolds number effect and the unsteady aerodynamic properties. Interaction between flapping wing of insects and the air flow became one of important and fundamental research topics in micro air vehicle. The present work is aim to investigate the flow behavior of flapping wings of tethered scarab beetle. The generation mechanisms of velocity field and vortex formation are visualized with smoke-wire method. Tethered flight of the drone beetle shows the motion with elastic deformation of flapping wing. Measured flapping frequency is about 71 Hz and its frequency is higher than for dragonfly and butterfly. Beetle decreases negative lift by feathering motion in the upstroke process and increase positive lift by effect of wake capture in the downstroke process.

中文翻译：

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无人机甲虫扑翼的可视化

昆虫扑翼的研究主要集中在低雷诺数效应和非定常气动特性上。昆虫扑翼与气流的相互作用成为微型飞行器的重要基础研究课题之一。目前的工作旨在研究系留圣甲虫拍打翅膀的流动行为。速度场和涡流形成的产生机制用烟线法可视化。无人机甲虫的系留飞行展示了扑翼弹性变形的运动。实测拍动频率约为 71 Hz，其频率高于蜻蜓和蝴蝶。甲壳虫在上行过程中通过顺桨运动减少负升力，在下行过程中通过尾流捕获的作用增加正升力。