Beetles have excellent flight performance. Based on the four-plate mechanism theory, a novel bionic flapping aircraft with foldable beetle wings was designed. It can perform flapping, gliding, wing folding, and abduction/adduction movements with a self-locking function. In order to study the flight characteristics of beetles and improve their gliding performance, this paper used a two-way Fluid-Structure Interaction (FSI) numerical simulation method to focus on the gliding performance of the bionic flapping aircraft. The effects of elastic model, rigid and flexible wing, angle of attack, and velocity on the aerodynamic characteristics of the aircraft in gliding flight are analyzed. It was found that the elastic modulus of the flexible hinges has little effect on the aerodynamic performance of the aircraft. Both the rigid and the flexible wings have a maximum lift-to-drag ratio when the attack angle is 10°. The lift increased with the increase of the gliding speed, and it was found that the lift cannot support the gliding movement at low speeds. In order to achieve gliding, considering the weight and flight performance, the weight of the microair vehicle is controlled at about 3 g, and the gliding speed is guaranteed to be greater than 6.5 m/s. The results of this study are of great significance for the design of bionic flapping aircrafts.

中文翻译：

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带有可折叠甲壳虫翅膀的仿生飞机滑翔飞行中气动性能的仿真分析

甲虫具有出色的飞行性能。基于四板机理理论，设计了一种新型的可折叠甲虫翼仿生扑翼飞机。它可以执行具有自动锁定功能的拍打，滑行，机翼折叠和外展/内收运动。为了研究甲虫的飞行特性并提高其滑行性能，本文采用双向流固耦合数值模拟方法研究了仿生扑翼飞机的滑行性能。分析了弹性模型，刚性和柔性机翼，迎角和速度对滑翔飞行中飞机空气动力特性的影响。发现柔性铰链的弹性模量对飞机的空气动力性能影响很小。当攻角为10°时，刚性翼和柔性翼都具有最大的升阻比。升力随着滑行速度的增加而增加，并且发现该升程不能支持低速时的滑行运动。为了实现滑行，考虑重量和飞行性能，将微型飞行器的重量控制在约3g，并保证滑行速度大于6.5m / s。这项研究的结果对仿生扑翼飞机的设计具有重要意义。微型飞行器的重量控制在3 g左右，滑行速度保证大于6.5 m / s。这项研究的结果对仿生扑翼飞机的设计具有重要意义。微型飞行器的重量控制在3 g左右，滑行速度保证大于6.5 m / s。这项研究的结果对仿生扑翼飞机的设计具有重要意义。