Abstract: 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．

Key words: 3D CAD model,Design reuse,Reusable region,Extended feature tree,Partial retrieval