Optimized Offset Algorithm for Pockets with Islands Using Vertex Offset= = Vertex Offset를 이용하여 Island를 포함한 pock 를 위한 최적화된 옵셋 알고리즘

다국어 초록 (Multilingual Abstract)

The offset edge algorithm is a common method for creating contour-parallel paths and has been widely studied. The method includes approaches such as a pair-wise intersection and Voronoi diagram. Different from these approaches, the method proposed in this paper discerns an optimized offset algorithm via the offset vertex and includes four steps as follows. (1) The offset vertices are computed based on bisectors (line-segment, line segment); (2) the validity of combining the direction and position checking for each offset edge is the main point of the proposed paper; (3) an efficient algorithm is constructed to connect all offset edges simultaneously to generate raw offset lines without local invalid loops; and (4) the offset-distance check is performed to remove the global invalid loops from the raw offset lines as well as interference loops in joining boundaries and multiple islands. The proposed method is verified with various slice contour shapes, with or without islands, and good results were obtained for significant reductions in the calculation time.

국문 초록 (Abstract)

옵셋 에지 알고리즘은 평행하게 외곽 경로를 순차적 옵셋으로 생성하는 일반적인 방법이고 폭넓게 연구되어 지고 있다. 이 알고리즘은 Pair-Wise Intersection과 Voronoi diagram과 유사한 접근방법이다. 본 논문에서 제시한 방법과의 차이는 다음과 같이 4가지로 요약할 수 있다. (1) 옵셋 점들은 Line-Segment의 이등분선을 이용하여 계산한다. (2) 각 옵셋된 에지들에 대한 방향 및 위치를 체크하여 옵셋된 에지들의 타당성을 체크한다. (3) 효율적인 알고리즘을 위해 유효하지 않는 로컬 루프가 없는 옵셋된 라인들을 실시간으로 연결하여 옵셋라인을 생성한다. (4) 옵셋거리체크를 이용하여 중첩된 옵셋 라인 및 유효하지 않는 글로벌 루프를 제거한다. 본 논문에서 제안한 방법은 다양한 단면 형상에 대하여 검증을 하였으며 상당한 계산시간의 단축을 얻었다.

목차 (Table of Contents)

• Chapter 1 Introduction = 1
• 1.1 2D line offsetting approach = 1
• 1.2 Research methods = 6
• 1.3 Organization of the thesis = 6
• Chapter 2 Background = 7
• 2.1 Introduction to CAD/CAM/CAE concepts and systems = 7
• 2.2 Overview of the design and manufacturing process = 9
• Chapter 3 Generating 2D line offset = 16
• 3.1 Computation offset vertex via bisector = 16
• 3.2 Direction checking and position checking = 17
• 3.2.1 Direction index = 17
• 3.2.2 Position index = 18
• 3.3 Generating raw offset line algorithm = 20
• 3.3.1 Data structure = 20
• 3.3.2 The raw offset line algorithm = 20
• 3.3.3 Raw offset line algorithm for Case 1 and Case 2 = 23
• 3.3.4 Raw offset line algorithm for Case = 324
• 3.4 Removal of global invalid loops = 27
• 3.5 Joining boundary and islands = 28
• Chapter 4 Implementation and some results = 30
• Chapter 5 Conclusion and future works = 33
• REFERENCES = 34
• Abstract in Korean = 37