基于语义的三维CAD模型可重用区域自动提取

Semantic-based Automatic Extraction of Reusable Regions in 3D CAD Models

针对产品设计中的局部检索重用需求,提出一种基于语义分析的可重用区域自动提取方法。通过采用扩展特征树表征三维CAD模型,准确刻画设计模型中不同粒度、不同形式的特征及特征间的关联关系,有效捕捉模型中包含的设计语义;通过分析局部区域的设计重用性,提出局部区域可重用性度量函数,并以扩展特征树的表征结构为输入,依据局部区域的可重用性自动提取候选可重用区域;通过进一步评价候选可重用区域的重用率确定最终可重用区域,以确保可重用区域的有效性及合理性。实验结果表明,依据本方法提取获得的可重用区域符合设计重用语义,能有效支持产品设计阶段的局部检索重用。

Aiming at the partial retrieval and reuse,a semantic-based automatic extraction approach of reusable regions was proposed.Giving an engineering part,the defined design feature model can accurately describe both its features with different scales and forms and the relationships between these features by using extended feature tree,so as to effectively capture the design semantics of the model.Furthermore,based on the analysis of reusable regions for design of 3D CAD models,a reusability metric function of a given local region was defined and an algorithm that automatically extracts its candidate reusable regions for inputted extended feature tree was put forward.Finally,for each extracted candidate reusable regions,its reuse rate in given library was calculated and those candidate reusable regions which have high reuse rates were identified as final reusable regions.The proposed approach was implemented and tested.Preliminary results show that the reusable regions which are extracted using this method meet the design reuse requirements,so as to effectively support partial retrieval for design reuse.