Function-Structure-Behavior Knowledge Integration For Product Design In Distributed Resources Environment

Product design is a process of knowledge flow,integration,competition and evolution.The knowledge integration is combining several knowledge pieces into a knowledge set which can answer the question proposed before.With the development of product design,the content of knowledge set is increasing,the design task becomes clear,and the descriptions of function knowledge,structure knowledge,and behavior knowledge are gradually completed and normalized.However,domestic enterprises generally have problems of insufficient design knowledge accumulation and limited ability to acquire professional knowledge in product innovation.It's hard for them to do product innovation by themselves.Under this background,how to conduct integrated design with distributed design knowledge is of great practical significance for improving enterprise knowledge acquisition ability,promoting knowledge flow among different organizations and guiding enterprises to carry out integrated design.Based on distributed resources environment,this thesis focuses on the researches of integrated design process,integrated design method and the application in tribology system design,and online service.The main works can be summarized as the following aspects:1.An integrated design process model in distributed resources environment,i.e.Requirement-Function-structure-behavior(RFSB)model,is established.Product design knowledge mainly includes function knowledge,structure knowledge,and behavior knowledge.Product design process can be described as transformation activities between different design knowledge.The thesis clearly defined and expressed the design knowledge,i.e.requirement knowledge,function knowledge,structure knowledge,behavior knowledge etc.Considering the design activities like problem formulation,structure synthesis,behavior analysis and solution evaluation,the thesis built the integrated design process model-RFSB model.The model is developed for distributed resources environment,which considered how to utilize outside resources in the product design process.2.Based on the RFSB model,a concrete mapping method from function knowledge to structure knowledge is proposed.Suh's axiomatic design mentioned that the transformation from functional requirement to design parameter is key design activity during product design process.But they haven't proposed a detailed mapping method to finish the transformation.In this thesis,a zigzag mapping method with supportive algorithm is proposed to finish the transformation from function knowledge to structure knowledge in distributed resources environment.Besides,the method is applied to the design of friction and wear testing machine.3.Based on the RFSB model,several mapping methods from structure knowledge to behavior knowledge are proposed.In distributed resources environment,many solutions will be generated for the same requirement.Hence,solution evaluation is important.The evaluation results rely on solutions' behavior knowledge which is derived from structure knowledge.The thesis defined connection between different function units and computing principles at the connecting points.Therefore,a mapping method from structure knowledge to behavior knowledge based on function unit structure diagram is proposed and applied into design evaluation of a friction-abrasion testing machine.In addition,the structure-behavior mapping method of mechanical system is always based on simulation and experiment.Taking the design evaluation of piston ring liner tribology system as examples,this thesis proposed the general steps of using simulation and experiment to acquire behavior knowledge.4.A knowledge integration network platform supporting RFSB model is built.This thesis classified knowledge services on the platform and explained how the platform supports RFSB model-based design process.For the simulation-based behavior knowledge acquisition module in the platform,this thesis discussed the publishing method,searching method,and implementation procedure of online service of simulation,and developed the software called connector to support the online service of simulation.It is applied into the joint tribological behavior calculation of piston skirt system and piston ring system.