近年來隨科技發展，微飛行器輕巧及擁有相當高機動性的特色，於救災與軍事領域有非常大的應用與發展空間。現今之拍撲式微飛行器設計大多參考現實中之飛行生物，其中蝴蝶比起其他昆蟲有較低的拍翅頻率，且以拍撲滑翔並用之飛行模式，部分物種能進行長距離之遷徙，這些特色使其成為微飛行器設計之非常良好的參考對象。而蝴蝶翅膀相較於其他昆蟲，其形狀變化相當大，因此本研究以此為動機，針對蝴蝶翅膀外型對其拍撲氣動力效應之影響，進行研究與探討。
本研究使用一兩自由度拍撲機構，模擬真實蝴蝶之拍撲動作，藉由於翼根處連接六軸力平衡儀進行力量量測，並配合粒子影像測速等流場可視化方法，針對不同翅膀外型對其拍翅產生升力之表現，以及其翅膀周圍之流場狀況與渦流結構進行分析與比較。升力量測結果發現翅膀之展弦比與其升力表現無明顯關聯，而翅膀之形心位置對升力表現的影響則較展弦比大。E型翅膀等翅膀形狀變化較小之翅膀，其下拍時之翼後緣渦流結構較完整且強度較強，而P型與K型翅膀形狀變化較大，對其翼後緣渦流之結構產生負面影響使其翼後緣渦流強度較弱。透過比較翅膀於展向面積變化最大的位置與其翼後緣渦流之環流量，可以發現翅膀形狀變化甚大的位置其翼後緣渦流亦明顯減弱。上拍時A型翅膀產生最大的負升力，其於三種翅膀則沒有明顯差距，流場結果可以看到翼前緣處明顯的翼前緣渦流貼附，以及強烈的展向流。比較翅膀於上拍結束時之尾流，A型翅膀之翼尖渦流與翼根渦流環流量大於其他種類之翅膀。
本研究之結果顯示，E型翅膀在此拍翅動作條件下能有最佳的升力表現，翅膀形狀變化劇烈會對翅膀渦流結構以及升力表現有負面影響。雖然本研究之結果無法完全對照於其參考物種之飛行表現，但仍可以作為未來仿蝴蝶微飛行器之翅膀形狀設計參考。

Recently, flapping-wing micro aerial vehicles (FWMAV) have become a popular research topic, due to their high maneuverability and wide application in rescue or scout operation. Many researchers have investigated the aerodynamic effects upon wing shape with rectangular or ellipse wing which similar to general insect wing. Compared to other insects, butterflies have relatively high diversity in wing shapes and the aerodynamic effects of high diversity in different wing shape have not been clearly understood. In this study, a two-degree of freedom flapping robot was designed and fabricated to replicate the butterfly flapping motion in the water tank. Four butterfly species with different wing shape was chosen as the reference of experiment wing model. The experiment used the force balance to measure the force produced by the flapping motion and the particle image velocimetry (PIV) was used to analyze the flow field and vortex structure around the wing. The force measurement result has shown that the aspect ratio has no significant correlation with lift coefficient, which is corresponded to other researches. And the centroid of area of the wing has a relatively high effect on the lift coefficient than the aspect ratio. From the PIV result, we found that the wing with a more complicated wing shape at the trailing edge has negative effects on trailing-edge vortex, and has a weaker vortex structure around the wing at downstroke, which is related to the negative effect on the lift production. At upstroke, all wing models have observed the leading-edge vortex and strong spanwise flow at the leading edge. The type-A wing model has the greatest negative lift at upstroke that is related to the strongest wing tip and wing root vortex, which is observed at the end of upstroke. Based on the force measurement and PIV result, we concluded that the type-E wing model has the best lift performance at this specific flapping motion, and complicated wing shape has a negative effect on vortex structure and lift production. Although the result couldn’t completely compare to the real nature species flight, but can still provide an important reference to FWMAV wing shape design.

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