果實蠅飛行升力之量測與分析

Abstract

本研究量測果實蠅在固定姿態下飛行所產生的平均升力以及平均升力和翅膀幾何形狀、體重等參數間的關係。我們為了這們目的，嘗試兩種不同設計的力量感測器。第一種設計能量測單一方向動態的振翅力，但力量的解析度較低。第二種設計對於平均飛行力有良好的解析度，而且能同時量測不同方向的振翅力，相對的無法量測振翅力的動態波形。在比較兩種感測器的優劣後，我們選用第二種設計作為實驗中的力量感測器。實驗分為視覺反應和最大升力量測。視覺反應的部份，探討果實蠅垂直升力和不同運動形態視覺條紋的關係。為了得到果實蠅的最大平均升力，以持續上升的條紋動畫刺激果實蠅飛行。

In this paper, we measured the average lift generated by tethered flies and investigated the relationship among the average lift, geometry of wings, weights and other parameters. For this purpose, we proposed two different designs of force sensor. The first design can measure the dynamic force in one direction. It has wide bandwidth but suffers with low resolution. The second design has high resolution for average lift measurements and can simultaneously measure forces in two directions. However, its fundamental frequency is low and hence can’t measure dynamic force. We chose the second design in our experiment after comparing the pros and cons of these two designs. The experiment includes two parts: visual response and maximum lift measurement. In the visual response experiment, we studied the effects of vertically moving stripes on the fruit flies. Different ways of stripe movement have been tested. We found that the upward moving stripes can stimulate the fruit flies to flap their wings harder. Then we measured the lift of fruit flies subjected the influence of upward moving stripes.