【摘 要】
：
A new approach is proposed to generate flexible featrure-based models (FFBM), which can be modified dynamically. BRep/CSFG/FRG hybrid scheme is used to describe
【机 构】
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CAD/CAM Research Center
论文部分内容阅读
A new approach is proposed to generate flexible featrure-based models (FFBM), which can be modified dynamically. BRep/CSFG/FRG hybrid scheme is used to describe FFBM, in which BRep explicitly defines the model, CSFG (Constructive solid-feature geometry) tree records the feature-based modelling procedure and FRG (Feature relation graph) reflects different knids of relationship among features. Topological operators with local retrievability are designed to implement feature addition, which is traced by topological operation list (TOL) in detail. As a result, FFBM can be modified directly in the system database. Related features chain reactions and variable topologies are supported in design modification, after which the product information adhering on features will not be lost. Further, a feature can be modified as rapidly as it was added.
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