Please use this identifier to cite or link to this item: `http://hdl.handle.net/11455/1487`
 標題: 含島嶼的口袋切削刀具路徑自動生成Automatic toolpath generation of pocket with islands 作者: 吳采芬Wu, Tsai-Fen 關鍵字: pocket;口袋;island;toolpath;voronoi diagram;pairwise intersection;島嶼;刀具路徑;佛柔尼圖法;兩兩相交法 出版社: 機械工程學系 摘要: 本研究的主要目的是發展一理論模式自動產生口袋切削刀具路徑。不論是多麼複雜的口袋形狀，只要合乎本研究的限制和問題定義皆可自動生成刀具路徑。 在線段排序方面，本研究以輪廓內一點判斷輪廓線段的排列方向，並提出一套獨特的找尋位於輪廓內一點的方法。在輪廓線段偏置方面，採用voronoi diagram產生退化點，比較退化點到對應線段的距離與偏置距離的大小，以判斷線段偏置後是否退化，再以兩線段間夾角大小決定兩線段之間連接的方法，其中關於交點的求取，本研究不以最小框盒法預先判斷兩線段是否可能相交，直接由推導數學公式求取交點，並陸續加入一些限制條件以得知線段是否有交點，以及探討特殊情況。在排除過切迴圈方面，我們捨棄傳統所使用頗覺複雜且麻煩的干涉指數演繹法，另外提出一個直覺且簡潔的方法。在產生刀具路徑方面，使用方向平行切削法產生刀具路徑，並可在刀具路徑轉成NC碼之前，模擬刀具路徑切削，以便得知產生的刀具路徑是否正確，減少錯誤的發生。最後舉出四個切削的例子驗證本文的可行性及實用性。The purpose of this study was to develop a new theoretical model that can be used to generate the tool-path for any user-defined contour with islands. For arrangement of entities, an originally special method was proposed and used to find a point inside the profile, which can help to determine the cutting direction along the profile automatically. For offset processing, the voronoi diagram was used to produce degenerative point. By comparing the offset of the line segment with the distance to degenerative point, whether the line segment after offsetting should be degenerated out or not can then be decided. And hence the included angle of two entities can be used to decide the way of connecting. As to the elimination of overcutting, an intuitive and versatile method was proposed to lessen the complexity in using the method interference index. Besides, a direction-parallel machining approach was adopted to generate the tool-path. Through the tool-path simulation, unnecessary bugs can then be avoided before NC encoding. Finally, four cases were presented in this study to verify the correctness and feasibility of this approach for practical application. URI: http://hdl.handle.net/11455/1487 Appears in Collections: 機械工程學系所