Research On Mechanical Product Variant Design Method Based On Ontology

Variant design plays an important role in the research and development of mechanical products.In the existing computer-aided design,the design knowledge,design formula and other information need to be determined manually by the designer based on experience.Different designers will possibly propose different design schemes,which greatly increases the subjectivity of product development and ultimately affects quality of products.In addition,variant design knowledge can not be effectively transferred between heterogeneous software systems and cannot support collaborative design,which reduces design efficiency.In order to further reduce the subjectivity in product development and improve design quality,this paper combines the ontology theory in the field of artificial intelligence with the field of mechanical engineering,and conducts research on the variant design of mechanical products.The main research contents of this paper are as follows:Constructed a hierarchical representation model of variant design information.Summarize the knowledge of the variant design domain,analyze the concept classes and their topological relationships involved in the variant design process.Using the top-down method,a variant design information representation model composed of four levels: part level,feature surface level,spatial relationship level,and parameter level is established.On this basis,the adjacency matrix is used to abstractly describe each level of the representation model,which provides preconditions for constructing the parameter index of the variant design process to generate the reasoning knowledge base.Constructed the semantic representation model of variant design ontology.According to the constructed variant design hierarchical information representation model,the OWL DL language is used to describe the concept classes,attributes and topological relationships of variant design by computer,and the definition domain and value range of the attributes involved in variant design are defined to complete the variant design.Construction of process ontology semantic model.Constructed the reasoning rules for variant design parameter generation.According to the analysis and summary of the knowledge of the experts involved in the variant design and the knowledge of the design manual,the Semantic Web Rule Language(SWRL)is used to compile the decision of the variant design process parts selection,dimensional parameter calculation,tolerance type generation,tolerance value generation,and processing method.At the same time,an intelligent algorithm for variant design is established.By converting the design knowledge acquired in this field into Jess reasoning rules,and using Jess reasoning engine for reasoning,the intelligentization of product variant design and knowledge transfer between heterogeneous software systems are realized.Develop a prototype system of variant design based on ontology.Based on the research on variant design in this article,the variant design ontology was constructed using the seven-step method,and the ontology was developed on the ontology editing tool Protégé;based on the developed variant design process ontology semantic model,the realization of the main functional modules of the prototype system was explained in detail process.The feasibility and effectiveness of the system are verified through engineering examples.