旋轉切削法為目前針頭組織切片術之主流切削方法，透過切向力之導入，除了可大幅降低切削時針頭所量測得之軸向切削力，亦可獲取較大尺寸與較好品質之軟組織樣本，為提升診斷精確度之關鍵要素。為深入了解針頭之旋轉效應對於切削行為之影響，以有效降低軸向切削力，本研究使用膠合性界面建模技術，建立一針頭旋轉切削軟組織之電腦數值模型。
本研究歷經兩個階段之數值模型建立過程：在第一階段，模型使用現有文獻作為結果之比較驗證與修正依據，以分析此建模技術之可行性；在第二階段，模型中套用了由實驗量得之吉利丁材料之應力應變關係與破壞韌性趨勢，並搭配混合模式破壞之概念，進一步與真實之穿刺及旋轉切削實驗做相互比對。經由文獻之初步驗證，研究結果顯示膠合性界面技術可用於模擬針頭組織切片之過程；在模擬與實驗之軸向切削力值方面也僅有約1%之誤差率。本模型接續產生更廣域切削參數下之軸向切削力反應曲面，成功預測可獲得最小軸向切削力之參數配置，實驗數據所擬合之反應曲面亦顯示出相同之結果。

The reduction of the cutting force in needle biopsy is believed to improve the diagnosis outcome. This study demonstrates a computational approach to simulate a rotating needle cutting soft tissue in needle biopsy with the use of surface-based cohesive behavior technology. Our FE model can accurately predict the cutting force of the needle, the difference in percentages is merely 1% between the simulation and experimental results. We also successfully predict the optimal cutting speed configuration for the minimal axial cutting force in the case of cutting gelatin samples. The approach will also be useful to other applications of biopsy or surgery cutting soft tissues or bones. Future improvements would be to create the cohesive surface in a way that does not require a predefined the fracture path and develop a protocol to obtain cohesive parameters through fracture tests.

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