Flow Characteristics around Flying Animal and Size Effects on Flight Mechanism

本研究项目涉及飞行动物的形态特征、振翅行为和气动特性。利用扫描电子显微镜对蜻蜓（Sympetruin infuscatum）、牛虻（牛虻）、虻（Tabanus rufidens）、蝇（Parasarcophaga crassipalpis）和醋蝇（Drosophila lutea）的翅膀进行了显微镜观察。观察了几个昆虫体表的横截面，并在个人电脑上对电子显微照片进行了图像处理。研究发现，在不同的位置，翼缘的形状和大小也不同。对于飞羽的结构，采用扫描电镜对鸽子羽毛进行了显微观察。三维运动分析系统揭示了飞行动物的翅膀运动。实验系统由两台高速摄像机、一个运动捕捉系统和一台个人计算机组成，对机翼运动进行了三维分析。对飞行动物的自由飞行进行了分析。揭示了昆虫飞行与其翅膀结构的关系。明确了爪哇麻雀的自由飞行行为，即定量地获得了鸟翼上位移和速度的时间变化。得到了鸟的翅膀运动轨迹和扑动的三维表达式。当爪哇麻雀的飞羽暴露在均匀光滑的风中时，飞羽发生弯曲，其弯曲特性在风向上表现出各向异性。每根飞行羽毛都有自己的弯曲特性。

This research project is concerned with the morphological characteristics, the wing beating behavior, and the aerodynamic characteristics of a flying animal. The wings of the dragonfly, Sympetruin infuscatum, the gadfly, Tabanus rufidens, the fly, Parasarcophaga crassipalpis, and the vinegar fly, Drosophila lutea were observed microscopically making use of the scanning electron microscope. Several cross section of insect costa were observed, and the image processing of the electron micrograph was conducted on a personal computer. It was found that the costa varies in shape and size corresponding to the location of wing. With respect to the structure of the flight feather, the pigeon feathers were observed microscopically using the scanning electron microscope. A three dimensional motion analysis system revealed the wing motion of the flying animal. The experimental system composed of two high speed video cameras, a motion grabber system and a personal computer, analyzed the wing motion in three dimensions. The free flight of theflying animal was analyzed. The relationship between the insect flight and its wing structure was reveald. The free flight behavior of the Java sparrow was clarified, that is, the time variation of the displacement and velocity on the bird's wing was obtained quantitatively. Wing path and flapping of the bird were obtained in three dimensional expression.When the flight feathers of the Java sparrow were exposed in the uniform smooth wind, bending of the flight feather occurs, and bending characteristics of the flight feather showed the anisotropy in the wind direction. Each flight feather has its own bending characteristics.