Product Intelligent Assembly Sequence Planning Based On Spatio-temporal Engineering Semantic Knowledge

With the development of economic globalization,the manufacturing enterprises have become more and more heated.Production efficiency and cost have become an important factor restricting the development of enterprises.Assembly is one of the most important,energy consuming and time consuming steps in the product manufacturing lifecycle.According to the statistics,the assembly time accounts for about 50% of the total manufacturing time of product,assembly costs account for about 25-35% of the manufacturing cost of product.Good assembly sequence can reduce 20-40% manufacturing cost and increase 100-200% production efficiency.Intelligent assembly sequence planning is an important means to reduce manufacturing cost and improve the level of product assembly automation in field of intelligent manufacturing.It becomes a research hotspot in field of digital design and intelligent manufacturing.It provides basis for assembly planning and scheduling in the industry 4.0,which reforms and upgrades manufacturing with computer technology,information technology.It has is an important theoretical value.Product modeling and assembly process contain abundant knowledge of spatio-temporal semantic engineering knowledge,which provides an important basis for intelligent assembly sequence planning.Therefore,product intelligent assembly sequence planning is proposed in this paper based on spatio-temporal engineering semantic knowledge.The spatio-temporal semantic information model and its ontology knowledge model are established.The spatio-temporal semantic knowledge system is built for product intelligent assembly sequence planning.The product spatio-temporal semantic knowledge is obtained.The assembly sequence generation based on spatio-temporal engineering semantic knowledge retrieval and rule reasoning is studied.The main research works are:(1)The spatio-temporal semantic information model of product is proposed.From two aspects of spatio-temporal semantic object and relationship,the expression of product spatio-temporal semantic knowledge is studied.The semantic knowledge model is established for CAD assembly model and priori knowledge of assembly sequence planning.With Protégé3.4.4 software,spatio-temporal semantic knowledge ontology model is built.Product spatio-temporal semantic knowledge system is established for intelligent assembly sequence planning.(2)Computer based COM technology,Microsoft Visual Studio 2005 and SolidWorks API are used as the implementation means to access internal data of the product CAD model,obtaining the product spatio-temporal semantic knowledge oriented assembly sequence planning.(3)Assembly sequence generation based on spatio-temporal engineering semantics knowledge retrieval and rule reasoning is studied.The fuzzy clustering method is used to get the sub-assembly.The knowledge retrieval based on multiple attribute matching and the reasoning based on spatio-temporal engineering semantic knowledge are studied.The assembly sequence of sub-assembly and assembly is generated by combination of knowledge retrieval and rule reasoning.The optimal assembly sequence is obtained by fuzzy comprehensive evaluation.On the basis of key technology research,the product intelligent assembly sequence planning system based on spatio-temporal engineering semantic knowledge is developed,including the system framework,the design and implementation of each module.The application of the intelligent assembly sequence planning example of the linear motor is carried out.In summary,the product spatio-temporal semantic information model proposed in this paper provides a theoretical basis for intelligent assembly sequence planning.The spatio-temporal semantic engineering knowledge retrieval and rule reasoning provides an implementation technology for intelligent assembly sequence planning.So it has important scientific significance and research value.