| In the field of machinery,long-term design activities generate a lot of CAD models,which contains a wealth of knowledge and experience of the designers.Therefore,exploring reusable resource from existing models has become an important means to shorten product development cycle and focus innovative design.In recent years,the ability of CAD models to describe process,functional,material and other non-geometric information continuously improves.The connotation and extension of CAD models is expanded greatly.Designers have to spend a lot of time to represent CAD model.The method to improve design efficiency is urgently needed.Research found that assembly models which reflect design intent in many aspects carry more abundant development information than part models.In product design process,in order to meet similar requirements,some design structures frequently occur in different assembly CAD models.From the view of information reuse,the frequent structures which have information integrity and generality are quality reusable assets.Based on the above analysis,this paper seeks to find a method for common design structure discovery in assembly models from multiple sources CAD models in order to reference and reuse valuable experience and knowledge from multiple angles.The main contents are as follows:1)The concept of attribute connection graphs(ACGs)is proposed to represent multi-source information of assembly models,in which the structure of ACGs shows the topology information.Parts’ name,type,material and other kinds of information are represented as attributes of corresponding elements.Two simplifications of ACG are implemented.ACGs are able to support assembly CAD model comparison and reduce the complexity of information analysis effectively.2)An approach for discovering common design structures in assembly models is proposed.At first,I establish similarity analysis for parts and connections.Then,clustering method is applied to classify the parts and connections,so as to transform ACGs of assemblies into clustered attribute connected graphs(CACGs).After this,a discovery algorithm that improves upon FFSM is used to identify common design structures in assemblies.This method can integrate functional,structural,process and other diverse information to obtain common design resources.Enterprises may build high-quality reusable design repositories assisted by this method.3)This paper analyzes function information of common design structures and establishes a method for design reuse.Two layers data structure to storage "common design structure in assemblies – function" information is built.Association rule mining is conducted with function constraint through the two layer data.Based on Apriori algorithm,algorithm for mining association rules of common design structure and function is set up.This method can reuse information of common design structure from various angles.4)In this paper,a set of board models and a set of reducer models are used to verify the feasibility and effectiveness of the method... |
