College of Mechanical and Electrical Engineering, Suqian University, Suqian, China.
IET Nanobiotechnol. 2022 Sep;16(7-8):273-283. doi: 10.1049/nbt2.12095. Epub 2022 Aug 12.
The bamboo weevil beetle, Cyrtotrachelus buqueti, has evolved a particular flight pattern. When crawling, the beetle folds the flexible hind wings and stuffs under the rigid elytra. During flight, the hind wings are deployed through a series of deployment joints that are passively driven by flapping forces. When the hind wings are fully expanded, the unfolding joint realises self-locking. At this time, the hind wings act as a folded wing membrane and flap simultaneously with the elytra to generate aerodynamics. The functional characteristics of the elytra of the bamboo weevil beetle were investigated, including microscopic morphology, kinematic properties and aerodynamic forces of the elytra. In particular, the flapping kinematics of the elytra were measured using high-speed cameras and reconstructed using a modified direct linear transformation algorithm. Although the elytra are passively flapped by the flapping of the hind wings, the analysis shows that its flapping wing trajectory is a double figure-eight pattern with flapping amplitude and angle of attack. The results show that the passive flapping of elytra produces aerodynamic forces that cannot be ignored. The kinematics of the elytra suggest that this beetle may use well-known flapping mechanisms such as a delayed stall and clap and fling.
竹象鼻虫的飞行模式独具特色。在爬行时，象鼻虫会将柔韧的后翅折叠并塞在坚硬的鞘翅下。在飞行过程中，后翅通过一系列由拍打力被动驱动的伸展关节展开。当后翅完全展开时，展开关节实现自锁定。此时，后翅充当折叠翼膜，并与鞘翅同时拍打以产生空气动力学效应。研究了竹象鼻虫鞘翅的功能特性，包括鞘翅的微观形态、运动学特性和空气动力学特性。特别是，使用高速摄像机测量了鞘翅的拍打运动，并使用改进的直接线性变换算法进行了重建。尽管鞘翅是通过后翅的拍打被动拍打，但分析表明其拍打翼轨迹是具有拍打幅度和攻角的双 8 字形图案。结果表明，鞘翅的被动拍打会产生不可忽视的空气动力学力。鞘翅的运动学表明，这种甲虫可能会使用众所周知的拍打机制，如迟滞失速、拍打和甩动。
