Please use this identifier to cite or link to this item: http://hdl.handle.net/11455/1888
DC FieldValueLanguage
dc.contributor.advisor莊勝雄zh_TW
dc.contributor.advisorS. H. Chuangen_US
dc.contributor.author邱成豪zh_TW
dc.contributor.authorChou, Cheng Haoen_US
dc.date2005zh_TW
dc.date.accessioned2014-06-05T11:41:57Z-
dc.date.available2014-06-05T11:41:57Z-
dc.identifier.urihttp://hdl.handle.net/11455/1888-
dc.description.abstract本論文之主要目的在於研究發展一套車床專用CAD/CAM系統,藉由自行輸入的直線、圓弧和自由曲線(Bezier、B-Spline、NURBS)作車削工件外形的設計,進而針對設計的外形作偏置(offset),再將偏置後的外形進行粗、精切的刀具路徑規劃,產生快速、有效率的刀具路徑,使能在合乎精度且無過切的的狀況下車削出所設計的工件外形。 對於外形曲線的偏置部分,應用原本用於封閉曲線的干涉指數演繹法作為基礎,解決自由曲線偏置後自交迴圈干涉的問題。利用Bezier曲線的凸殼特性和及位置誤差累積的觀念,將自由曲線分解成片段Bezier曲線來求取偏置曲線。在取得正確的偏置曲線後,可以針對所設計的外形特性選擇合適的刀具路徑產生法,得到正確的刀具路徑。 一般商業CAD/CAM專用軟體對於車床粗切刀具路徑的產生方法,最常用的程序有:軸向粗切削複合循環(G71)、端面粗切削複合循環(G72)和成形加工複合循環(G73)三種。為了避免粗切削時,發生切削到需要保留之材料的過切現象,在路徑規劃時必須針對不同車削工件外形特性選擇合適的刀具路徑產生程序組合。本系統提供其中兩種(G71和G72)切削路徑程序來產生切削上的安全區域,藉以得到合乎精確、完整的車削工件。 關鍵字:車床,刀具路徑規劃,NURBS曲線,Bezier曲線,偏置zh_TW
dc.description.abstractThe purpose of this thesis is to develop a CAD/CAM system for lathe machining. Users can design the geometry of a workpiece by elements which include types of lines, arcs and freeform curves(Bezier, B-Spline and NURBS curves). After offsetting the designed contour, efficient tool paths for rough cut and finish cut can be generated to lathe machining, the designed workpiece contour satisfying the precision requirement without gauging. As to the contour offsetting, interference index method is applied to solve the self-intersecting loop interference problems for freeform curves. The convex hull property of Bezier curves and the idea of accumulative position errors are used to obtain offset curves by decomposing freeform curves into piecewise Bezier curves. After correct offset curves have being obtained, tool paths are generated by proper path generation methods according contour shape characteristics. In most commercial CAD/CAM softwares, three commonly used procedures are include in the path generation method: repetitive turning cycle(G71), repetitive facing cycle(G72) and pattern repetitive cycle(G73). In order to avoid undercutting in rough cut, proper combination of procedures for path generation are chosen according to the contour characteristics of the designed workpiece. This system provides two lathe machining cycle procedures(G71 and G72) to produce secure zone in machining, such that an accurate and intact designed workpiece can be lathe machined. Keyword: lathe, tool path generation, NURBS curve, Bezier curve, offset.en_US
dc.description.tableofcontents目錄 中文摘要.........................................................I 英文摘要.........................................................II 第一章 緒論.....................................................1 1.1 研究背景................................................. 1 1.2 研究目的與方法.............................................2 1.3 文獻回顧與探討.............................................3 1.4 內容大綱..................................................6 第二章 車削工件之設計系統 .........................................7 2.1 系統操作介面..............................................7 2.2 複合曲線定義及演繹法.......................................9 2.2.1 Bezier曲線...............................................9 2.2.2 B-Spline曲線.............................................10 2.2.3 NURBS曲線................................................14 2.2.4 節點插入演繹法............................................16 2.3 複合曲線資料結構..........................................18 第三章 車削工件之偏置曲線產生.....................................20 3.1 直線與圓弧偏置產生........................................20 3.2 直線逼近NURBS曲線與偏置...................................22 3.3 幾何位置不連續之消去......................................27 第四章 車床之刀具路徑規劃........................................30 4.1 複合形固定循環切削........................................30 4.1.1 軸向粗切削複合循環G71.....................................31 4.1.2 端面粗切削複合循環G72.....................................35 4.1.3 精切削加工循環G70........................................38 4.2 特殊外形之車削刀具路徑規劃.................................38 第五章 執行與範例...............................................42 5.1 系統架構.................................................42 5.2 實際範例.................................................43 第六章 結論與展望...............................................52 6.1 結論....................................................52 6.2 未來展望.................................................53 參考文獻.........................................................54zh_TW
dc.language.isoen_USzh_TW
dc.publisher機械工程學系zh_TW
dc.subjectlatheen_US
dc.subject車床zh_TW
dc.subjecttool path generationen_US
dc.subjectNURBS curveen_US
dc.subjectBezier curveen_US
dc.subjectoffseten_US
dc.subject刀具路徑規劃zh_TW
dc.subjectNURBS曲線zh_TW
dc.subjectBezier曲線zh_TW
dc.subject偏置zh_TW
dc.title含NURBS曲線之車床刀具路徑產生zh_TW
dc.titleTool Path Generation with NURBS Curves for Latheen_US
dc.typeThesis and Dissertationzh_TW
item.fulltextno fulltext-
item.languageiso639-1en_US-
item.openairetypeThesis and Dissertation-
item.cerifentitytypePublications-
item.openairecristypehttp://purl.org/coar/resource_type/c_18cf-
item.grantfulltextnone-
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