基于加工特征的B-rep模型几何变换算法  

Geometric Updating Method for B-rep Model Based on Machining Features

作　　者：马善坤[1] 刘长安[1] 方文涛[1] 

机构地区：[1]山东大学机械工程学院CAD/CAM研究所

出　　处：《组合机床与自动化加工技术》2012年第4期20-24,共5页Modular Machine Tool & Automatic Manufacturing Technique

摘　　要：为了真实反映加工过程中零件的几何变换情况,对边界表示法模型的特征尺寸的改变和特征的删除方法进行了研究。基于拓扑结构保持不变的前提下,提出了通过延长特征邻接边实现面特征在法向方向上尺寸改变的几何更新算法和几何形状规则的特征的删除算法,针对几何形状不规则的非独立特征,提出了通过面对齐和合并面处理来实现特征删除的算法。经过几何变换后,确保零件模型面壳封闭,保证模型的合理性和完整性,能够通过模型重构映射零件的实际加工情况。最后通过软件实例验证了方法的可行性。To simulate the geometric change of parts during machining,the paper studied the method of changing the dimension of features and deleting features on B-rep model.Proposed a geometric updating method for dimension changed along the normal of face feature and removal of regular shape feature through extending the adjacent edges of the feature.Proposed a feature deleting method for irregular shape feature through face alignment and face merging.Ensured the model shell is closed and the completeness and rationality of the B-rep model after geometric updating and reflected the practical machining situation quite well through model reconstruction.At last verified the feasibility of this method through software system.

关 键 词：边界表示法 拓扑结构 特征删除 模型重构 

分 类 号：TH16[机械工程—机械制造及自动化] TP391[自动化与计算机技术—计算机应用技术]