模具零件的最小包围盒生成算法  

Generation algorithm of minimum bounding box for die & mould components

作　　者：孔垂品[1] 牛强[1] 柳伟[1] 周雄辉[1] 

机构地区：[1]上海交通大学模具CAD国家研究中心,上海200030

出　　处：《模具工业》2014年第4期15-18,共4页Die & Mould Industry

摘　　要：提出一种实用的最小包围盒算法,将任意位置的复杂三维模型投影在3个主平面上,通过分析投影外轮廓的最小包围矩形来最终确定三维模型的最小包围盒。算法不再采用传统算法中旋转模型的方法,而根据旋转投影的外轮廓来确定最小包围盒,提高了算法的效率。同时算法通过分析识别模型的基本形状,将其分为箱体类、回转类和异形类,以快速确定一个主投影方向,将三维问题转化为求二维平面上的最小包围矩形,进一步提高了计算效率。算法可以嵌入NX等商用CAD系统,经过大量测试对比,相对传统算法更高效,并且稳定可靠,可广泛应用于任意位置的复杂模具零件的生成和干涉检查等。A practical algorithm of minimum bounding box was proposed in which a com- plex 3D model at arbitrary position is projected on three principal planes; and then the minimum bounding box of the 3D model is determined by analyzing the minimum bound ing rectangle of outer contour projection. The algorithm no longer uses the rotating model in traditional method; the minimum bounding box is determined according to the outer con tour of rotating projection to improve the efficiency. The algorithm classifies the basic shape of models as box type, rotary type and abnormal type to rapidly determine a main direction of projection. It translates the 3D problem into the minimum bounding rectangle on 2D plane to further improve the computational efficiency. The algorithm can be implant ed in the commercial CAD system such as NX and so on. The application can be in the blank generation and interference checking of complex die ＆ mould components at arbi trary position.

关 键 词：最小包围盒 投影外轮廓 零件分类 模具 

分 类 号：TG76[金属学及工艺—刀具与模具] TP391.72[自动化与计算机技术—计算机应用技术]