Data for: Passive wing deployment and retraction in beetles and flapping microrobots

All data used in the article: <b>Passive wing deployment and retraction in beetles and flapping microrobots</b><b>Abstract</b>Birds, bats and many insects can tuck their wings against their bodies when at rest and deploy them to power flight. Whereas birds and bats use well-developed pectoral and wing muscles¹^,², how insects control their wing deployment and retraction remains unclear because this varies among insect species. Beetles (Coleoptera) display one of the most complex mechanisms. In rhinoceros beetles, <i>Allomyrina dichotoma</i>, wing deployment is initiated by complete release of the elytra and partial release of the hindwings at their bases. Subsequently, the beetle starts flapping, elevates the hindwing bases and unfolds the hindwing tips in an origami-like fashion. Although the origami-like fold has been extensively explored³^,⁴^,⁵^,⁶^,⁷^,⁸, limited attention has been given to the hindwing base movements, which are believed to be driven by the thoracic muscles⁵^,⁹^,¹⁰^,¹¹. Here we demonstrate that rhinoceros beetles can effortlessly deploy their hindwings without necessitating muscular activity. We show that opening the elytra triggers a spring-like partial release of the hindwings from the body, allowing the clearance needed for the subsequent flapping motion that brings the hindwings into the flight position. After flight, the beetle can use the elytra to push the hindwings back into the resting position, further strengthening the hypothesis of passive deployment. We validated the hypothesis using a flapping microrobot that passively deployed its wings for stable, controlled flight and retracted them neatly upon landing, demonstrating a simple, yet effective, approach to the design of insect-like flying micromachines.

本文所用数据来源于：<b>《甲虫与拍打式微型机器人的机翼被动展开与收拢》</b>
<b>摘要</b>
鸟类、蝙蝠与多数昆虫在休憩时可将翅膀收拢于躯体之上，飞行时再将其展开以提供动力。尽管鸟类与蝙蝠依靠发达的胸肌与翼肌完成相关动作^1,2，但昆虫如何调控机翼的展开与收拢这一问题尚未明确，且该机制因物种不同而存在差异。
鞘翅目（Coleoptera）甲虫的机翼调控机制便是其中最为复杂的一类。以双叉犀金龟（<i>Allomyrina dichotoma</i>）为例，其机翼展开过程始于完全打开鞘翅（elytra），并部分释放基部的后翅（hindwings）。随后甲虫开始拍打翅膀，抬升后翅基部，并以类似折纸的方式展开后翅尖端。
尽管这类折纸式折叠结构已得到广泛研究^3,4,5,6,7,8，但学界对后翅基部的运动机制关注不足——此前普遍认为该运动由胸部肌肉驱动^5,9,10,11。本研究证明，双叉犀金龟可在无需肌肉参与的情况下，轻松完成后翅的展开动作。研究发现，打开鞘翅会触发后翅如同弹簧般从躯体上部分释放，为后续拍打动作留出足够空间，使后翅得以进入飞行姿态。飞行结束后，甲虫可借助鞘翅将后翅推回休憩姿态，进一步验证了被动展开的相关假说。
本研究通过一款拍打式微型机器人（flapping microrobot）验证了该假说：该机器人可被动展开机翼以实现稳定可控的飞行，并在着陆后整齐收拢机翼，证明了一种简洁高效的类昆虫微型飞行机器设计方案的可行性。