工程图公差和粗糙度向三维模型的映射技术

摘要

配合企业对基于MBD的产品设计和制造需求,为解决工程图与三维模型的标注映射问题,针对工程图中的形位公差和粗糙度,提出一种基于图匹配的工程图向三维CAD模型的标注映射算法.首先,基于DXF中性文件提取形位公差和粗糙度；然后,关联形位公差粗糙度和与之对应的工程图图元；建立三维模型投影所得的投影视图和工程图的空间关系图,对两个空间关系图进行图匹配；最后,获得工程图形位公差和粗糙度与三维CAD模型标注平面的关联.实验结果表明,该算法可以很好地实现工程图形位公差和粗糙度向三维CAD模型的标注映射.%With the development of the demands of MBD based product design and manufacturing to the enterprises,the problem of dimension mapping between the 2D engineering drawing and the CAD model should be considered.Aiming at the form and position tolerance and surface roughness in engineering drawing,a dimension mapping technology is proposed.Firstly,tolerance and roughness are extracted based on DXF files.Secondly,the relationship between dimensions and corresponding drawing primitives are organized.Thirdly,the projection drawing of 3D model and engineering drawing are represented as spatial relation graph which can be matched by graph matching method.Finally,the mapping information of tolerance and roughness is obtained.Experimental results show that the technology is able to support the dimension mapping and the mapping efficiency meets the requirement of practical applications.