Büsse Sebastian, Koehnsen Alexander, Rajabi Hamed, Gorb Stanislav N
Department of Functional Morphology and Biomechanics, Institute of Zoology, Kiel University, Am Botanischen Garten 9, 24118 Kiel, Germany.
Sci Robot. 2021 Jan 20;6(50). doi: 10.1126/scirobotics.abc8170.
The biomechanics underlying the predatory strike of dragonfly larvae is not yet understood. Dragonfly larvae are aquatic ambush predators, capturing their prey with a strongly modified extensible mouthpart. The current theory of hydraulic pressure being the driving force of the predatory strike can be refuted by our manipulation experiments and reinterpretation of former studies. Here, we report evidence for an independently loaded synchronized dual-catapult system. To power the ballistic movement of a single specialized mouthpart, two independently loaded springs simultaneously release and actuate two separate joints in a kinematic chain. Energy for the movement is stored by straining an elastic structure at each joint and, possibly, the surrounding cuticle, which is preloaded by muscle contraction. As a proof of concept, we developed a bioinspired robotic model resembling the morphology and functional principle of the extensible mouthpart. Understanding the biomechanics of the independently loaded synchronized dual-catapult system found in dragonfly larvae can be used to control the extension direction and, thereby, thrust vector of a power-modulated robotic system.
蜻蜓幼虫捕食性攻击背后的生物力学原理尚未被理解。蜻蜓幼虫是水生伏击性捕食者，它们用经过大幅改造的可伸展口器捕获猎物。我们的操纵实验以及对先前研究的重新解读可以反驳当前认为液压是捕食性攻击驱动力的理论。在此，我们报告了一个独立加载同步双弹射系统的证据。为了为单个特化口器的弹道运动提供动力，两个独立加载的弹簧同时释放并驱动运动链中的两个独立关节。运动所需的能量通过拉伸每个关节以及可能周围的角质层中的弹性结构来储存，这些结构通过肌肉收缩进行预加载。作为概念验证，我们开发了一个受生物启发的机器人模型，它类似于可伸展口器的形态和功能原理。了解蜻蜓幼虫中发现的独立加载同步双弹射系统的生物力学原理可用于控制动力调制机器人系统的伸展方向，从而控制其推力矢量。
