机械

从零件的CAD模型中获取工艺设计所需的加工特征信息是CAPP的基础,也是实现CAPP与CAD集成的关键。研究旨在探讨中等复杂程度机械零件的加工特征识别方法。采取方法是从三维设计软件中得到CAD模型,对该模型输出的STEP AP203文件进行处理,获得面特征及其连接边的凹凸性,得到属性邻接图,将其进行处理得到全凹(或全凸)连接的子图,然后将子图中所有代表毛坯面的节点去掉,剩下的就是各特征对应的特征子图。再按照特征子图匹配法,将每个子图与预先定义的特征图进行匹配,就得到了所需要识别的特征。实例结果显示该方法是简便有效的,大大减少了图匹配的计算量。

It is very important to obtain machining characteristic information from CAD model in order to designing techniques and realizing CAD and CAPP integration. The purpose is to probing into machining geometric features means for medium complex degree mechanical parts. The means is first to getting CAD model from three-dimensional software,then to dealing with STEP AP203 neutral file from CAD model to obtaining surface features and concave convex character ,and to finding and disposing attributed adjacency graph in order for all concave or all convex sub-graphs. Every characteristic sub-graph is matched with predefine characteristic graph according to characteristic sub-graph methods to getting required discriminating characteristics.The result is very convenient and effective to decreasing graph matching time from the example.