近年來隨著醫療科技的進步，人工智慧(Artificial intelligence, AI)與醫療的結合也備受重視，為使機械手臂應用於手術以增加其準確性，需大量的數據來輔助該技術之發展，故將探討生物組織之接觸行為。除此之外，在病理及病徵方面，生物組織之機械性質也扮演著重要的角色，例如：2019年新冠病毒肺炎(Coronavirus disease 2019, COVID-19)大流行，而肺部纖維化為肺炎常見之後遺症，此將影響肺部機械性質，故本研究將使用豬之肺部組織進行探討。
在本研究中將對豬肺進行球形壓痕及應力鬆弛試驗，並探討其不同壓痕深度、速度及位置之差異，接著將實驗數據對Ogden超彈模型及Generalized Maxwell黏彈模型進行曲線擬合以獲得其超彈及黏彈參數，並利用有限元素法進行建模驗證這些參數之準確性，且與線彈模型進行比較。最後因生物組織表面多具有組織液及血液等液體，故加入擠壓軟彈液動模型使擠壓過程更貼近現實，並探討在不同操作參數下之壓力、膜厚及變形量等特性。
實驗結果顯示，以壓痕及應力鬆弛試驗可以很好的描述生物組織的超彈及黏彈效應，而透過曲線擬合公式中接觸半徑的修正，可以更準確的獲得生物組織的超彈及黏彈參數。利用有限元素法進行建模以驗證參數的準確性，透過比較發現線彈模型在大變形下無法很好的描述應力及應變關係，而超彈則較為準確，且兩者在加入黏彈性後亦是如此。最後以先前獲得的參數進行擠壓軟彈液動建模，並與乾接觸模型比較發現在擠壓初期之變形量、壓力等有明顯的不同，並探討了不同速度下的壓力及膜厚特性。

關鍵字：生物組織、超彈性材料、黏彈性材料、軟彈液動潤滑

In recent years, with the advancement of medical technology, the combination of artificial intelligence (AI) and medical treatment has also received much attention, so the contact behavior of biological tissues will be discussed. In addition, in terms of pathology and symptoms, the mechanical properties of biological tissues also play an important role, for example: Coronavirus disease 2019 (COVID-19) pandemic in 2019. Pulmonary fibrosis is a common sequelae of pneumonia, which will affect the mechanical properties of the lungs. Therefore, this study will use the lung tissue of pigs to investigate.
In this study, spherical indentation and stress relaxation tests will be performed on pig lungs, and the experimental data will be curve-fitted to the Ogden hyperelastic model and Generalized Maxwell viscoelastic model to obtain its hyperelastic and viscoelastic parameters. The finite element method is used for modeling to verify the accuracy of these parameters. Finally, because the surface of biological tissues mostly contain tissue fluid and blood and other liquids, the squeezing soft-EHL model is added to make the squeezing process closer to reality, and its characteristics such as pressure, film thickness and deformation are discussed.

Keywords: biological tissues, hyperelastic materials, viscoelastic materials, soft-EHL

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