Journal of Mechanical Science and Technology 26 (10) (2012) 3201~3212 www.springerlink.com/content/1738-494x DOI 10.1007/s12206-012-0827-3 Name matching method using topology merging and splitting history for exchange of feature-based CAD models † Sang-Uk Cheon 1 , Duhwan Mun 2 , Soonhung Han 3 and Byung Chul Kim 4,* 1 Information Technology R&D Team, Daewoo Shipbuilding & Marine Engineering Co., Ltd, 1 Aju-dong, Geoje, Gyeongsangnam-do, 656-714, Korea 2 Department of Precision Mechanical Engineering, Kyungpook National University, 386 Gajang-dong, Sangju, Gyeongsangbuk-do, 742-711, Korea 3 Division of Ocean Systems Engineering, Korea Advanced Institute of Science and Technology, 373-1 Gusong-dong, Yuseong-gu, Daejeon, 305-701, Korea 4 Department of Mechanical Engineering, Dong-A University, Hadan 2-dong, Saha-gu, Busan, 604-714, Korea (Manuscript Received October 8, 2011; Revised April 23, 2012; Accepted May 16, 2012) ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Abstract A feature is generated by referring to topological entities in a solid model. It is essential to persistently name the topological entities re- ferenced by the feature. This problem is known as the persistent naming problem. The persistent naming problem is divided into naming and name matching. The persistent naming problem is an important issue in the exchange of feature-based CAD models through a neu- tral format. If a CAD model contains only construction history, the naming of the topological entities is required during translation. How- ever, if a CAD model contains modification history as well, name matching is also required. In a previous study, the authors proposed a naming method for exchanging feature-based CAD models. In this study, a solution to the name matching problem is proposed and its technical details are discussed. The proposed name matching method is based on the local matching technique, using topology merging and splitting history. The feasibility of the proposed name matching method has been demonstrated through experiments with a prototype CAD model translator. Keywords: Feature-based CAD model exchange; Name matching; Persistent naming; Topology merging and splitting history ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- 1. Introduction Feature-based modeling is a popular means for generating the shape of a product and capturing design intents in a com- mercial CAD system. Modeling through a feature-based CAD system includes features, constraints, and parameters, in addi- tion to boundary representation (B-rep) model data, which represent the detailed shape of the model. To represent shape models, feature-based CAD systems adopt a hybrid method; this method contains both a procedural model and an explicit model. The procedural model is represented in terms of the operations used in a modeling session. In feature-based CAD systems, the operations are called features. In this regard, the feature tree of a CAD system corresponds to the procedural model. The explicit model is represented by the B-rep model, which represents the detailed geometric information. Gener- ally, several B-rep elements are associated with each modeling operation. Each feature of a feature tree is generated by referencing the topological entities of the existing B-rep model, and the result- ing B-rep model can be referenced later by other features. A mechanism for identifying topological entities should there- fore be provided in feature-based modeling. A mechanism for finding the same topological entity in the new model (post- edit model) corresponding to the referenced topological entity in the old model (pre-edit model) is also required when feature definitions, parameters, or constraints of a CAD model are modified. This problem is generally known as the persistent naming problem [2, 3]. Because of global competition, manufacturers must offer high-quality products at low prices. In such a business envi- ronment, the time to market is very important. Collaborative design is widely used to reduce product development time. The exchange of feature-based CAD models among different CAD systems and the sharing of product models are key tech- nologies for enabling collaborative design because they allow the easy editing of CAD models [4]. Two strategies are available for enterprises wishing to ex- change CAD models in computer-readable form, the use of * Corresponding author. Tel.: +82 51 200 7641, Fax.: +82 51 200 7656 E-mail address: mir7942@dau.ac.kr † Recommended by Associate Editor Ki-Hoon Shin © KSME & Springer 2012