以B-rep為基礎之圓角特徵簡化技術發展

黃駿(Chun Wong)

指導教授 ： 賴景義

國立中央大學/工學院/機械工程學系/碩士(2014年)

摘要

因應塑膠產品需求的日益升高，需在製造前經過電腦的模擬分析。而建構模型的網格時經常因模型的細小特徵，建構出品質不佳的網格，為了提升品質需以人工的方式逐一調整網格，因而浪費大量的時間。為了減少人工調整之花費時間，本研究將簡化模型中的圓角特徵，以降低模型的複雜程度，藉此提升網格的品質。本研究以了解模型的B-rep資料結構為基礎，擷取圓角的周邊資訊，以此推算簡化後的形狀，並改變其拓撲與幾何資料，以達到簡化之目的。對於圓角簡化後的結果，本研究以商業軟體CADdoctor作為驗證的依據，以得到正確之簡化結果。

關鍵字

特徵簡化 ； B-rep ； 圓角

並列摘要

In response to the increasing requirement for plastic products, the design should be analyzed before manufacturing through appropriate computer aided engineering technology. In CAE analysis, meshes with bad quality appear quite often owing to the existing of tiny features on the CAD model. To improve the quality of the analysis, the meshes need to be adjusted one by one, which requires significant manual efforts. In order to reduce the efforts of adjusting meshes manually, the aim of this study is to present a method for the simplification of fillets. By simplifying the fillets, the complexity of the model can be reduced and hence the quality of the meshes can be improved. This study is based on the understanding the B-rep model. It captures the information with respect to a fillet, and calculates the simplified shape of it. By changing the topological and geometric data near the elements on the fillet, the fillet can be simplified. The CADdoctor is employed and compared with the proposed algorithm to verify the feasibility of the proposed method.

並列關鍵字

feature simplification ； B-rep ； fillet ； blend face

參考文獻

[13] 游子威，以B-rep為基礎之混接曲面辨識技術發展，國立中央大學機械工學系碩士班論文，2014.

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