基于STEP的相交特征识别

目的构建基于STEP的制造特征识别系统，研究系统中的特征识别尤其是相交特征识别的实现方法．方法在VC＋＋6．0和ST—Developer集成环境下，应用MFC类库和ROSE库等进行系统的构建及程序和数据的处理，并以STEP中性文件AP203和AP224分别作为系统的输入和输出文件．结果所构建的系统实现了具有相交特征的制造特征识别，其特征识别技术是采用基于图的特征识别方法；针对特征相交中两种不同类型的相交实体，分别采用不同的方法对加工面邻接图进行了有效的分解．结论以AP203文件作为特征识别系统输入文件，实现特征识别系统与CAD系统的无缝连接；经过特征识别所生成的特征符合AP224中所定义的制造特征模型，有力地支持了基于STEP的CAD＼cAPP＼CAM数据集成技术，所采用的制造特征识别方法能够识别普遍的相交特征．

Research on Recognition of Intersection Features Based on STEP

The purpose of this paper is to construct a machining feature recognition system based on STEP, then to study the implement methods of feature recognition, particularly in intersection features recognition. This paper uses MFC classes and ROSE database etc. for the system construction and program data processing in the VC ＋＋ 6.0 and ST - Developer integration environment, STEP neutral file AP203 and AP224 are utilized respectively as the input and output files of feature recognition system. Constructed system implements machining feature recognition of the intersection features, whose technology is based on the method of graph-based feature recognition;for the two different types of interacting entities, MFAG （Manufacturing Face Adjacency Graph）is effectively decomposed by different methods. The AP203 file is utilized as input file of feature recognition system, which achieves a seamless connection between feature recognition system and the CAD system. The feature generated by the feature recognition corresponds to feature modeling based on AP224, which makes the realization of the CAD ／CAPP ／CAM data integration technology based on STEP highly effective. This machining feature recognition method can recognize general interaction features, but it has its restriction.