基于形体分析的零件尺寸自动标注

采用面向对象的方法建立零件尺寸信息模型,描述面向尺寸标注的零件数据,进而给出了零件尺寸自动标注算法,以及尺寸标注知识的表达方法.详细讨论了算法中基于零件拓扑结构与特征成形等的形体分析,图元尺寸自动生成与特征关联尺寸及冗余尺寸等的识别优化,以及基于特征包围盒的尺寸布局等关键步骤的实现.设计开发了零件尺寸自动标注系统,通过在航空发动机涡轮盘等零件工程制图中的应用,证明该方法能够高效生成准确性高、符合规范且排列整齐的零件尺寸.

Automatic Dimensioning of Parts Based on Geometric Entity Analysis

A model of part dimensioning information,which was used to describe part data for automatic dimensioning,was developed by an object-oriented method.An automatic dimensioning algorithm and its knowledge representation method were presented.Some key problems of the algorithm were discussed in detail,including the geometric entity analysis based on part topologies and features,the automatic dimensioning of drawing elements,the recognition and optimization of feature-related dimensions and redundant dimensions,and the dimension layout based on feature bounding boxes.An automatic dimensioning system was developed and applied to the engineering drawing of an aero-engine turbine disk.The result shows that the dimensions generated by this system are accurate,standard and well arranged.