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540Research on the structure of green-product integration development systemJiang Jibin, Wu Qisheng, Lin Jiuguang, Liu Zhifeng, Liu GuangfuHefei University of Technology, Hefei 230009, ChinaABSTRACTIn order to conduct green design effectively andscientifically, it is an important premise to build Green-product Integration Development System orienting productlife-cycle. In this paper, viewed from practicality andintegration, current green products design tools are firstlyanalyzed, the structure of current accessible green-productintegration development system is secondly discussed, andthe strategy of system development from practicality andintegration is lastly brought forward. *1 SUMMARYGreen-product is compatible with environment, resourceand energy. Its green attribute is implemented on its whole life-cycle. Green-product development means that its function andstructure. are designed and the green degree of the life-cyclesdifferent stage is virtually designed and assessed its digital-product stage. So the demands of time, quality, cost etc. arefulfilled on the precise of meeting environment and resourcesdemands. There are many design tools about green-productdesign now. But most of them which are on theoretic stagearent integrated with traditional design tools such as CAD,CAM etc and can not support the enterprises productdevelopment. This paper studies on the structure of currentaccessible green-product integration development system anddiscusses the strategy of system development on the base ofanalyzing the specialties of green-product development frompracticality and integration.The aims that different computer aided tools can fulfill arenot the same as each others. For example CAD mainlycompletes products geometrical modeling. On the contrary,different aims of functions decide the structure of diversesystem. So at the beginning of implementing systemdevelopment, only to know well the functional aim ofestablished system to be fulfilled, and only to apply those aimto instructing system planning and software development, canone assure the system to be established meeting functionaldemand.The aims of traditional designs theories and methods areto meet products function, quality, time, and cost. These* This project is supported by the Nation Natural ScienceFoundation of China 59935120demands include the functions of satisfying customers, need,high quality, short manufacturing cycle, and low cost. Greendesign adds environmental aim comparing to traditional designand is centered by environmental protection. As to eliminatethe potential negative effect, it emphasizes on the bondagebetween products fundamental attributes and environmentalattributes. The environmental aim is a wide concept. Itincludes a series of problems such as ecological environment,resource, and the utility of energy etc. The problem aboutecological environment means that it affects ecologicallyenvironment on its whole life-cycle. For example, polluted airand used water generated on manufacturing procedure affectecological environment, whats more, the products which aredisposed can affect ecological environment also. The utility ofresource means the capacity of resource , especial non-recycle resource is utilized comprehensively and optimized.Then the aim is very important because resource isincreasingly scarce. Though products green attribute isimportant when it is on manufacturing, using and disposedstage, it is decided on product development (digital productor blueprint) stage. Then we can achieve the goat ofproducts minimum affect on ecological environment,minimum energy consumption, maximal resource using if onlyif we understand it well and regard environment as one aim byrational design of product structure when we is developingproducts.We can make a conclusion from above analysis: Green-product development not only includes traditional designwhich is applied to fulfill products function but also carriesout environmental capability design., so the computer aidedsystem which is applied to support Green-productdevelopment has characters of multi-tool and integration, andthis point must to be considered when the structure of green-product development system is planned.2 THE STRUCTURE OF CURRENT GREENPRODUCT DESIGN TOOLThe research about green product has been widely carriedout since Alting introduced life-cycle engineering in 1993.Many research institutes and universities have studied anddeveloped some green product design tools while manytheories have been pointed out after many years research.Those tools not only validated these theories pointed out butalso supported designers informational design tools. Thecurrent main green design tools is listed on section 3.5.2 inReferences1, and by analysis on those tools, the structure ofthe system is mainly divided into two style: single-toolstructure and integration structure. This section will analyzetheir characters and applied field as to support theoreticallythe structure of green product development system which isbased on uniform product model introduced in this paper.nts5412.1 Single-tool StructureGreen design references to the analysis and estimate ofproducts green attributes in life-cycle. It is a multi-fact andmulti-attribute decision-making process. Early green designtools adopted single-tool structure and developed operatingtools for a particular design content. The system existed aloneand could not communicate with other design tools. Forexample, DFDS(Design For Disassembly System)developedby HeFei University of Technology belongs to this kind ofstructures.Figure 1 The Structure of DFDSFigure 1 is the structure of DFDS. This system acquiresinformation about the structure, assembling and parts, andconstructs product net-graphic model by information inputtingsystem. It calculates parts disassembly direction and createsproducts disassembly sequence by some relative algorithmabout applied graphic and analyzing disassembly plan which isbased on net-graph model. Then it estimates productssustainability by analyzing disassembly time and disassemblyproblems. It finally creates files about estimating result whichare supplied to the designers , and to be applied to modifyproducts design.The research and development of DFDS supply an aidedtool which can analyze the ability of disassembly for designers.DFDS can achieve interactive disassembly and prompt theresearch and development of sustainability design and greendesign. But the system adopts single-tool structure, it hassome disadvantages. Many yearsresearch on CAD that indicates informationabout product structure, geometry, andassembly is so much , complicated anddiverse that it is difficult to be expressed bysimple data structure. DFDS is developed byVC+, because the data structure which isused to store product information is limited, itis too difficult to acquire entirely information,and it is only applied to several parts; It isnot integrated with development tools such asCAD etc. Then it results to input informationagain and again and not feedback the estimating resultautomatically. The visual-ability of product anddisassemblys process is limited. Whats more, its operationis relatively abstract.2.2 Integration StructureIntegration structure regards information integration as theaim. It realizes the integration of product developmentprocess and supports the information exchange and transferamong CAx (CAD, CAPP etc) and DFx (DFA, DFD etc.) bybeing supplied uniform data model (product model ormanagement model).According to data model, the structure of productintegration development system is divided into two categories:(1) Integration structure based on uniform product datamodel This structure plans every life-cycle developmenttool as a whole system. Product development is based onuniform product data model. It can achieve systemic highintegration and shared information of a system. It is shown infigure 2(a). It constructs product integration developmentsystem platform by encapsulating development tools withuniform application interface. Different users carry outdifferent product developments basing on this platform. Theinteractive action between development platform and productmodel is implement by product data management. Then theyachieve information exchanging between development toolsand shared information and integration in the process ofproduct development. The essence of this system is productintegration model which is applied to exchange, save,pigeonhole of product data in the whole life-cycle. Integrationstructure which is based on uniform product data modelreferences to uniform and product integration model includinglife-cycle information about the product. It discards everydevelopment tools special database. At the same time, itconstructs semantic relation between different tool data bymanaging product model data. Then it avoids datesredundancy and non-consistence between dates. Whatsmore, the advantage of product model with applied publicdata format is that it can reduce the developments of data-exchange processor. So researchers can spare more time torealizing the function of development tools, but not realizingsystem integrative data exchange.(a) (b)Figure2 The System of Integration Structure(2) integration structure based on uniform datamanagement model The structure is based onPDM(Product Data Management), and integrates manyfunctional software on uniform PDM platform, and achievesintegration management of information and process. It isData-exchange processorPDM systemIntegration productmodelProduct data managemenDevelopment system platformSpecialty productmodelSpecialty productmodelProduct informationAnalysis resultInformationinputtingInformationmodelingDisassemblyplanning Base information Part information Assembly information Net graph model Layer relation Disassembly direction Disassembly sequence ProductData BaseProduct modelUser interfaceDFA DFD DFxCAD CAPPCAxDevelopmentToolsbasal modelAppliedbasal modelProfessionalapplied modelKnowledge baseKnowledgeResourceUniversalknowledgeProfessionalknowledgents542shown on figure 2(b). PDM usually adopts product data andmodel management based on product structure model. Thereis plenty of redundant dates in applied files because onproduct structure model only proscribes the relation betweenprofessional product model and each applied system. Theconsistence check of files content can not been carried outby product dates management system either. Low-layerapplied systems is forced to establish Mechanism of input andoutput conformed by standards such as STEP and IGESetc. because it lacks an integrative data model. On the otherhand, the work amount is very large. So it is difficult to assureveracity of transforming data from one systemic productmodel to another.3 THE STRUCTURE OF GREENPRODUCT INTEGRATIONDEVELOPMENT SYSTEMGreen attribute is the essential character of green product.Because what green attribute references to mainly ismanufacturing, using, and disposing which are on life-cyclesmaterial stage. So it usually adopts simulating way on thedigital stage of product development. It also constructs virtualmanufacturing, using and disposed environment on computerand predicts future green products character. In the future itappraises product green attribute on the basis of product andmodifies irrational design affecting green attribute. Theproduct to be developed finally reaches scheduled green aims.On the other hand, product development references to othersimulating characters besides green attribute such assustainability and manufacturing-ability of product. Thosecharacters need digital product model too. So product modelwith uniform structure, no redundant information and orientedthe whole life-cycle are the bases of realizing green productdevelopment , and it must to be considered carefully whenresearchers are planning product development system.According as above discussions, we think that the integrationsystem based on uniform product data model should bepreferred structure. What is shown in figure 4 is the structureof integration development system based on uniform productmodel. This system mainly consists of some components.Figure3 The Structure of Green Product IntegrationDevelopment System(1) Development tool Product development systemsupplies correspondent supporting development tools whenproduct is oriented for different applied demands in life-cycle.They are computer aided tools (CAx) and Design for X tools(DFx), and CAx is a platform that can meet demands inspecial fields of product design. Such as CAD, CAPP andCAM etc, modeling product and planning manufacturingprocess can be finished on this platform; DFx developed onthe basis of CAx is technology and a tools that can meet life-cycle demands, it considers thoroughly what product affectson later procedure of product design stage, such as assembly-ability, manufacturing-ability and maintain-ability etc, designersconsider as many factors as possible which can affectfunction by appraising every CAx designing results andrational decisions. Then it makes product achieve an optimumaim that synthesizes each functional index in the whole life-cycle.(2) Product model and model managementProduct model is the object manipulated by design activity. Itis the essence of green design, and is the data and informationset of product. We consider it consists of different layermodel from figure 4. The first model is basal model which isnot relative to concrete application, such as productgeometrical model. The second model is applied basal modelwhich references to applied function, such as precision modeland resource & environment model. The third model isprofessional applied model for particular application, such asFinite-Element net model. Effective application of productmodel need supporting from management model. Managementmodel and product model are usually combined into onefunctional unit. It can realize interactive information betweendevelopment tool and product model by controllinginformation exchange and storing. Then shared and integratedinformation among all development tools can be achieved.Model management mainly consists of data managementwhich is based on product structure and the mechanism oftransforming model information into applied requirementinformation.(3) Knowledge base and knowledge managementKnowledge base stores much information about all sorts ofapplied knowledge which references to product development.These information is the applied basis of every developmenttool and necessary for designing and estimating project. Allinformation is divided into three layers by its specialties anduniversal character. The first layer is knowledge which isrelated to project and applied field. Such as design rule ofaxial parts and the rule of selecting cutting parameters. Thesecond is knowledge which is related to particular productdesign. Such as enterprise standard and knowledge aboutenterprise manufacturing resource. The third is knowledgewhich is independent of application. Such as materialstandards and mechanical drawing standards. The storing andutility of knowledge data is realized by knowledgemanagement system. These knowledge for product designapplied demand which supports the being carried out projectis delivered to development tool by knowledge managementsystem interface.(4) User interface Each development tool(CAxand DFx), product model and knowledge base areencapsulated as a uniform development platform for designers.Each development tool can be harmoniously applied toprocess of product development by user interface. By userinterface, the storing and acquiring of data and knowledge iscontrolled consistently, and then the uniformly management ofprocess and information is realized. So it is possible to realizeintegrated and parallel product development.One important character of this structure is the modelbased on uniform product. Each life-cycle development tooland shared information is realized by enclosure of userinterface. Then it can ensure that developed product achievesnot only traditional structure and function aim but alsoenvironmental green aim. So green product can besuccessively developed.4 THE IMPLEMENT STRATEGY OFGREEN PRODUCT INTEGRATIONDEVELOPMENT SYSTEMPro/E and UGII which are both commercial supportingsoftware supply functional module such as design, model,analyze, NC programming and manufacture etc. Theyemphasize on product structure and manufacturing process,and they havent functional module such as about analysisand estimating environment affected by product and dontnts543support correspondent green design tool. But This sort ofsystem is open and integrated partially. Viz. The systemsupplies three-dimension modeling. Uniform product datamodel can be constructed by the software. and at any moment,product geometrical and functional description can beacquired for product development tools, such as CAPP andFinite-Element analysis, etc. The system suppliescustomization modeling. It supplies input interface of projectapplied information about tolerance and material attribute, andmakes a technical basis for constructing product model whichincludes life-c