在微飛行器的開發過程中，面臨了傳統定翼機在低雷諾數時氣動力效率不佳的問題，在觀察了自然界飛行生物的飛行方式後，發現以拍撲飛行的飛行方式可以有效改善低雷諾數飛行中氣動力效率低下的問題。
本研究針對拍撲飛行的地面效應進行研究，透過二維拍撲機構使翅膀的拍撲角與扭轉角進行正弦函數的運動，搭配高度可調整的地面平台進行地面效應的實驗。實驗結果發現不同動作參數下，對地距離在兩倍弦長以上時升力係數不會受地面影響，對地距離小於兩倍弦長時升力係數會有急遽上升的現象。此外，雷諾數在地面效應中扮演十分重要的角色，在雷諾數5000的低雷諾數動作中，翅膀對地距離最近時升力係數僅有不到10%的成長，但在雷諾數20000的高雷諾數動作中，升力係數的漲幅高達25%以上。以相同雷諾數但不同拍翅振幅運動時，每個動作的升力係數的漲幅曲線都十分相似，唯拍翅振幅 的動作在最地距離是兩倍弦長的時候有升力係數下降的現象。本實驗還另外透過量測翅膀表面壓力中心的位置，推測拍翅行程中段的地面效應的形成，是透過地面改變翅膀與來流之間的有效攻角，進而導致升力產生變化。本實驗在拍撲飛行的地面效應中取得了一定程度的升力量測的成果，希望在將來本實驗的研究成果能夠成為拍撲飛行的地面效應理論的基石，並成為微飛行器開發者在起飛降落階段的參考。

In the process of micro aerial vehicle(MAV) development, the problem of poor aerodynamic efficiency of fixed-wing aircraft at low Reynolds number was encountered. By observing the flight strategy of flying creatures in nature, it was found that the flying type of flapping flight can effectively improve the problem aforementioned.
This research focuses on the ground effect of flapping flight. A two-dimensional flapping mechanism is used to make the flapping angle and twisting angle of the wings moving in a sinusoidal function. The ground effect experiment is carried out with a height-adjustable ground platform. The experimental results show that under different Reynolds number and flapping amplitude, the lift coefficient will not be affected by the ground when the distance to the ground is more than twice of the chord length, and the lift coefficient will rise sharply when the distance to the ground is less than twice of the chord length. In addition, the Reynolds number plays a very important role in the ground effect. In the low Reynolds number (Re=5000), the lift coefficient of the wings only grows less than 10% when the distance to the ground is the closest, but in the high Reynolds number (Re=20,000), the lift coefficient increases by more than 25%. When moving at the same Reynolds number but with different flapping wing amplitudes, the increase curve of the lift coefficient about each movement is very similar, except that the lift coefficient decreases when the minimum distance is twice the chord length. In this study, we also analyzed the position of the center of pressure on the surface of the wings. The results show that the ground effect in the middle wing stroke changes the effective angle of attack, between the wings and the incoming flow through the ground, which causes the variation of the lift force. We also verify the variation of effective angle of attack through the PIV measurement. In this study, we investigated the ground effect of flapping flight under different flight condition which expanded the understanding of the ground effect theory in flapping aerodynamics and also provided the significant references for the manipulation of during take-off and landing.

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