CAD(Computer-Aided Design)實體模型之特徵簡化技術被廣泛使用於CAE (Computer-Aided Engineering)分析之相關作業。執行CAE分析時需以CAD模型幾何外觀建立分析網格，而模型中細小特徵容易產生劣質的分析網格，進而導致CAE分析結果不夠精確，因此若能簡化模型中細小特徵，有助於提升CAE分析之精準度。其中導角半徑較小之圓角為常見的細小特徵，因此本研究擬發展整體與局部圓角簡化技術，以修正CAD模型之B-rep(Boundary representation)資料結構的方法，建立簡化圓角後之尖銳邊與刪除圓角資訊，以便達到簡化目的。藉由此技術可避免劣質分析網格產生，以提升後續CAE分析之正確性。最後本研究將以40個實際CAD模型進行案例驗證，且獲得良好之測試成功率，以證實本研究具有一定程度之正確性與可行性。

Feature simplification technics can be extensively used in CAE (Computer-Aided Engineering) analysis. In CAE analysis, the need of building up analysis meshes by CAD (Computer-Aided Design) model geometric appearance is indispensable, and subtle features in the model are prone to generate poor quality of analysis meshes which led to CAE analysis of results inaccurate, therefore, simplifying subtle features in the model contributes to CAE analysis accuracy. Fillets which have small radius are common subtle features, hence this thesis intends to modify B-rep(Boundary representation) data of CAD model in order to suppress fillet features which have small radius in the model, thereby avoiding producing poor quality of analysis meshes and improving subsequent CAE analysis accuracy. More than 40 realistic CAD models were tested, and almost all of the fillets on these models were simplified successfully, which can verify the feasibility of the proposed method.

摘要 I
Abstract II
誌謝 III
目錄 IV
圖目錄 VI
表目錄 IX
第一章 緒論 1
1.1前言 1
1.2文獻回顧 2
1.3本實驗室先前研究回顧 4
1.4研究目的與方法 10
1.4.1研究目的 10
1.4.2研究方法 12
1.5論文架構 15
第二章 B-rep資料結構與圓角簡化相關名詞 16
2.1前言 16
2.2 B-rep資料結構 16
2.3圓角分類與名詞介紹 22
第三章 圓角簡化方法與演算法流程 28
3.1前言 28
3.2圓角簡化整體方法 28
3.2.1前置處理 31
3.2.2圓角分群 34
3.2.3建立圓角簡化後的元素 38
3.2.4刪除圓角相關的元素 50
3.2.5修繕拓樸資訊 50
3.3 局部簡化演算法介紹 53
3.3.1圓角型態轉換 53
3.3.2修繕計算新尖銳邊之演算法 57
第四章 案例測試與討論 61
4.1前言 61
4.2 CAD模型測試 61
4.3問題討論 64
第五章 結論與未來展望 75
5.1結論 75
5.2未來展望 76
參考文獻 78

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