Study On The Method Of The Digital Process Design Of The Passenger Vehicle’s Assembly Line Based On Knowledge

The passenger vehicle’s assembly line(PVAL)is closely related to the design and manufacturing process of the passenger vehicles,which can reflect the cost and quality of the passenger vehicle and other key indicators that can affect the market share.With the rapid development of the passenger vehicle and the manufacturing technology,PVAL needs to be accordingly upgraded.The PVAL process design is the core of production line design.The purpose of the PVAL process design is to select a feasible,efficient and low-cost manufacturing route on the premise of guaranteeing the quality of the products.However,in the transformation and upgrading process to digital,information-based and intelligent process design,the Chinese PVAL design institutes share some universal problems such as insufficient design knowledge reserve,difficulty in flexible knowledge reuse and lack of practical tools.How to use the existing design knowledge,experience and tools to better support the designers in completing the process design tasks and improve the quality and efficiency of process design is an urgent problem to be solved.Based on this situation,this paper focuses on the representation method of the PVAL’s process design knowledge,intelligent recommendation method of design knowledge,and intelligent virtual assembly method of the three-dimensional(3D)digital models.The main contents are as follows.(1)A PVAL’s digital process design method and the framework are studied.Based on the analysis of existing PVAL’s design method,according to the PVAL’s process design requirements,a digital PVAL’s process design method that improves the design quality by intelligent knowledge recommendation and the design efficiency by 3D digital models’ intelligent virtual assembly is proposed.The framework of the method is presented.(2)A PVAL’s process design knowledge modeling method based on the ontology and complex network theory is studied.Based on the analysis of the PVAL’s process design,the basic elements of the PVAL’s process design are divided into five categories:designers,tasks,knowledge,resources and process,and the knowledge is further subdivided.The explicit knowledge and the other four kinds of elements are modeled using the ontology technology.A 3D complex network model(3D-CNM)among designers,tasks and knowledge is constructed based on the complex network theory.The construction method,structure and the corresponding engineering meaning of 3DCNM are detailed given.(3)A PVAL’s process design knowledge intelligent recommendation method based on correlation-experience-demand is proposed.To solve the problem that the current knowledge recommendation algorithms insufficiently consider multiple factors simultaneously,based on the analysis of the PVAL’s process design knowledge recommendation principles and the support of the ontology model and 3D-CNM,an intelligent knowledge recommendation method is proposed.The method comprehensively considers the correlation between knowledge and tasks,the designer’s feedback to the knowledge,the type and amount of information of the knowledge,and the experience and memory ability of the designer.Contrast experiments show that the proposed knowledge recommendation method can effectively meet a designer’s requirements.(4)An intelligent assembly method for 3D digital models based on the assembly knowledge model is proposed.When assembling the PVAL’s 3D digital models,a proper assembly scheme is recommended based on the assembly knowledge model.If the scheme does not meet the designer’s requirement,the designer’s assembly intention is intelligently recognized by dragging the 3D digital models,therefore the assembly process is rapidly completed.Contrast experiments demonstrate the proposed intelligent assembly method has obvious superiority in improving the virtual assembly efficiency,reducing the workload of designers and the operational complexity.(5)A PVAL’s design institute is taken as the subject to implement the proposed digital process design methods.The methods are concreted based on the institute’s process design process,and then a digital process design platform oriented to the PVAL is designed and developed.The development ideas,software framework,modules and data integration method are presented.The meaning and the effectiveness of this paper is validated by the implementation of the platform.