本研究的主要目的，是在微奈米尺度下，藉由掃描探針顯微鏡，觀察並討論真實水黽腳表面的剛毛結構，以及踩水時與水的接觸角和潤濕程度受表面粗糙度的影響，並探討水黽腳的彈性模數和整體構造對踩水浮力的影響。首先，本研究先利用掃描電子顯微鏡對水黽腳微結構做詳細觀察，並建立水黽腳表面的剛毛模型。以此模型為基礎，藉由淺深度下壓力的限制，建構合理的水弧面，並利用前進角的概念找出水弧面停滯點位置。由此，可以討論有/無剛毛表面結構下，對整體潤濕程度和接觸角的影響。也將水黽腳從內部剛毛到外部整體腳的接觸角變化做一個完整的連接。
接著，設計一空壓實驗來推算出水黽腳的彈性模數，且因為少了其它節腳和關節的影響，此彈性模數的真實性也較高。然後利用此彈性模數，對水黽腳踩水浮力作一數值運算模擬，建構出在不同踩水深度、入水角度以及水黽腳長度的變形量、浮力、踩深和3D踩水水窪。
最後，探討水黽腳的第三節腳對整體腳踩水浮力的影響，藉由與單一第二節腳的空壓、踩水實驗以及模擬的比較，我們發現第三節腳對整體腳踩水的等效剛性和所受浮力相較於單一第二節腳而言都有明顯的提升。由此可了解到水黽腳的第三節腳對整體腳踩水時的貢獻，除了有帶頭牽引二、三節腳以低角度入水外；也會支撐著前端水弧面，當繼續踩深時，前端不會容易被水覆蓋而使整體腳沒入水中。

In present study, the contact angles has been measured both water strider’s seta and leg, and the meniscus of leg in water is also be calculated and simulated. In this paper, the simulations of seta’s cross-section are considered from the images of SEM, and building up the proper water bridge profile between setae and seta’s groove are based on the limit of pressure. Advance angle theory is applied to find the exact stagnant position of the water bridge on the laterial surface of a groove and two setae. Then show the effect of with or without the seta roughness to final contact angle.
The elastic modulus of water strider’s leg is also be interested, and by designing a simple experiment can lead us to calculate the value. Using the result and a series of numerical schemes, the 3D- dimple, deflection, buoyancy and depth in water can be simulated.
Lastly, discussing the effect of the third section leg to the whole leg. With the result of experiments of the leg, we find that the equivalent stiffness of the leg and the ability of producing buoyancy are greater than the leg withouting the third section.

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