面向工程图样智能理解的关系模型

提出面向工程图样智能理解的关系模型,该模型由“一图、一树、二链”的视图关系图、尺寸树、几何元素投影关系链、尺寸约束图形链所构成,关系模型建立在表达方式处理、投影关系处理、尺寸约束处理三个层面上。在视图划分、尺寸预分离和坐标系建立的基础上,表达方式处理主要解决视图识别、视图关系图的建立;投影关系处理主要解决线素打断与拼接、几何元素投影关系链的建立;尺寸约束处理主要解决尺寸树建立和尺寸约束图形链的形成。从而为工程图样智能理解作好技术准备。

Relation Model Oriented to Intelligent Comprehension of Engineering Drawings

This paper proposes the relation model which made up o f a relation graph of views including "one graph, one tree, two lists", a dimen sion tree, a relation list of geometry element projection and a graphic list of dimension restriction. The relation model is built on three lays: the processing of expression mode, the processing of projection relation and the processing of dimension restriction. Based on the view partition, dimension departing and the reference frame building, the processing of expression mode mainly resolves the view recognizing and the building of the relation graphs of views. The processi ng of projection relation mainly resolves the cutting and connecting of elements and the building of the relation list of geometry element projection. The proce ssing of dimension restriction mainly resolves the building of the dimension tre e and the graphic list of dimension restriction. All of the actions are to make technique preparations for the intellective comprehend facing to engineering dr awings.