会员注册 | 登录 | 微信快捷登录 QQ登录 微博登录 | 帮助中心 人人文库renrendoc.com美如初恋!
站内搜索 百度文库

热门搜索: 直缝焊接机 矿井提升机 循环球式转向器图纸 机器人手爪发展史 管道机器人dwg 动平衡试验台设计

   首页 人人文库网 > 资源分类 > PDF文档下载

外文翻译--基于知识的机械设计独立研究 英文版.pdf

  • 资源星级:
  • 资源大小:1.06MB   全文页数:7页
  • 资源格式: PDF        下载权限:注册会员/VIP会员
您还没有登陆,请先登录。登陆后即可下载此文档。
  合作网站登录: 微信快捷登录 支付宝快捷登录   QQ登录   微博登录
友情提示
2:本站资源不支持迅雷下载,请使用浏览器直接下载(不支持QQ浏览器)
3:本站资源下载后的文档和图纸-无水印,预览文档经过压缩,下载后原文更清晰   

外文翻译--基于知识的机械设计独立研究 英文版.pdf

___________________________ReceivedDateSeptember29,2010BiographyPHYOWaiLin1978,male,borninShwebo,Myanmar.Ph.Dcandidate,mainresearchfieldisindependentknowledgebaseddesign.kophyobuaagmail.com1IntroductionProductdesignproceduredependsondesignersexperienceseriously.Byusingdesignersknowledgeandexperience,productmanufacturerscanreduceproductcostandproducehighqualityproducts.Designermust,however,drawuponexperientialengineeringknowledgesuchaspastexperiences,specificdesignrulesandprocedures.Mostdesignersneedtogetthecorrectgeometricinformation,parametersandfindnongeometricfeatureinformationfromthemechanicaldesignhandbookmanuallywhichareprettytimeconsuming.ParametricmodelingCADsystemsarebasedonthegeometricalrelationshipsbetweenparts.Partscanbetransformedbyvaryingdimensionseasily.However,nongeometricalknowledgeabouttheproductdesigncannotbemanagedeasily1.SomecommercialCADsystemsignorethisissue.ThereforeKnowledgebasedengineeringKBEhasbeenpresentedtomeetthedemandsofengineeringdesignmethodssincethelastof1980s.KBEisasubsetofknowledgeBaseSystemKBSwhichisaspinofffromartificialintelligenceAI.KBEisthemethodologyforTheResearchofIndependentKnowledgeBasedMechanicalDesignPHYOWaiLin,XIPing,ZHANGBaoyuan,CHENRuizhiSchoolofMechanicalEngineeringandAutomation,BeijingUniversityofAeronauticsandAstronautics,Beijing100191,ChinaAbstractMostofKBEsystemsappliedbypreviousresearchersaredependentonsomeCADsoftware,whichmakesknowledgehardtobereusedtootherCADsoftware.IndependentknowledgebasedsystemisindependentofCADsoftwarethereforeknowledgecanbereusedfreely.Thispaperdescribesindependentknowledgebasedsystemformechanicaldesign.Adetaileddiscussionabouttypicaldesignisputforwardincludingdesignprocessimplementationbasedonknowledgeengineering,independentknowledgebaseddesignarchitecture.Themainprincipalofknowledgedrivenengineeringisexplained.TheimplementationofKBEonthedesignofwormreducerisstudiedasacase.Independentknowledgebasedreducerdesignsystemisrealized.TheusageofindependentknowledgebasedsystemmakesKBEsystemworkindependentofCADsoftware,whichenhancestheirportabilityandfertilizesthecollaborativeworkofheterogeneousCADsystems.KeywordsknowledgebasedengineeringindependentknowledgebasereducerKnowledgeInterpreterKICLCNumberTP391DocumentCodeAArticleID10034951201002000107Vol.20No.2CADDMDecember2010capturingandstructuringknowledgewhichisusedtodefineengineeringmethodsandprocedures2.Typicalknowledgebasedsystemisbasedonobjectorientedprogramminglanguageandistightlyintegratedwithageometricmodelingtool,AI,designersexperience,databaseandsoon.Fig.1isthetypicalKBEdesignarchitecture.Fig.1KBEdesignarchitectureInrecentyears,theapplicationofCAx,AIandKBEtechnologieshavebeendevelopingfordesignandmanufacturingsystems.RichardCurran,WimJ.C.Verhagen,TonH.vanderLaanandMJTvanTorrenincorporatedtheKnowledgeOptimizedManufactureanddesignKNOMADmethodologywithinKBE3fortheanalyticalutilizationofmanufacturingknowledge.C.B.Chapman,MartynPinfolddescribesaknowledgebasedengineeringsystemKBEStoextendthecurrentcapabilitiesofautomotivebodyinwhiteBIWengineer4.PabloBermellGarciaandIpShingFanappliedKBEsystemforthedesignandmanufacturingofawindtunneltestingmodelofaircraftnacellesbyadoptionandcombinationoftheproductionrulesandtheobjectorientedknowledgerepresentation5.MostoftheKBEsystemsappliedbypreviousresearchersaredependentonsomeCADsoftware,whichmakesthemquiteinconvenientfortheknowledgetobereusedtootherCADsoftware.IndependentknowledgebasedsystemisindependentofCADsoftwarethereforeknowledgecanbereusedfreelyinvariousCADsoftwaresuchasUG,CATIA,Solidworksetc.2GoalofKnowledgeModelingGoalofthisresearchistogetknowledgedrivenparametricmodelbyusingindependentknowledgebasedsystem.Thereforetherelationshipbetweengeometricalandnongeometricalattributeisbasicconceptfortheframeworkofknowledgemodel.TheGeometricdescriptionisonlyonepieceofinformationaboutthetotalproductmodel6.Fig.2istherelationofgeometricandnongeometricattribute.Intheparametricmodelingoftheproduct,entitiesareassociatedwithgeometricparametersuchasabooleanprimitive,alineorarcinawireframe,orafilletingoperation.Theseparameterscontrolandplaythevariousgeometricattributessuchasheight,width,length,volumeandareaofthemodel.Theyalsocontrolthelocationsoftheseentitieswithinthemodel.KnowledgemodelDesignparameterNongeometricGeometricparameterGeometricKnowledgedrivenParameterdrivenFig.2GeometricandnongeometricattributesPower,weight,material,life,speedratio,loadandmanufacturabilityareincludedinthenongeometricattributesthatmeantheyaredesignparameter.Geometricandnongeometricattributesareinterrelated.Forexample,thepitchlinevelocityofthewormisVwπdwnw/12.GeometricpropertiesdwpitchdiameterandnongeometricpropertiesVwpitchlinevelocityaredependenttoeachother.TheinputstotheKBEmodelcontaingeometricandnongeometricattributeswhichcanincludedesignspecifications,designpractices,engineerexpertise,materialpropertiesandstructuralanalysis.Thekey2PHYOWaiLin,XIPing,ZHANGBaoyuan,CHENRuizhiCADDMresearchcontentofKBEistogetgeometricparametersoutfromnongeometricparameters.Theoutputisknowledgemodelwhichmeetscustomersdemands.3KnowledgeAcquisitionandRepresentationKnowledgeAcquisitionKAisthetransformationofknowledgefromtheforminwhichitexistsbetacitorexplicitintoformsthatcanbeusedinaknowledgebasedsystem.TheprocessofcollectingdomainknowledgeandtransformingtheknowledgeintoacomputerizedrepresentationKAincludestheelicitation,collection,analysis,modelingandvalidationofknowledgeforknowledgeengineeringandknowledgemanagementprojects3andinvolvesbreakingdown,grouping,structuring,chainingupandcontrollingtheknowledge.Animportantproblemishowtoextractknowledgefromanexpertandhowtorepresenttheelicitedknowledgeinaknowledgebasedsystem.KAcansolvethatproblembyconsideringthepurposeandfunctionofthedesiredinformation.KBEsystemsuseacombinationoftheproductionrulesandtheobjectorientedknowledgerepresentationastherepresentationparadigms.Fig.3istheknowledgerepresentationchartofresearchworktocontrolandmodifyknowledgethatneedsacollectionofvariousformsofknowledge,includingMathematicalformulas,Rules,experience,parametricmodel,formandchartformechanicaldesignparametricmodel.Knowledgeimplementationfortypicaldesignmodel,designknowledgecanbecategorizedasfollows1MathematicalformulaInthemechanicaldesign,therearemanyareasofmathematicalformsofknowledge.Manydesignpartssuchassize,material,strengthandsoonneedthecomplexmathematicalcalculationsandderivationtogettheirappropriatevalues.Mathematicalformulasincludingexpressionsarithmeticexpressions,logicalexpression,etc.,differentialequationsandintegralequationandsoonthatisusedforthedesignMathematicalCalculationChartTableParametricModelExpertiseRuleIFTHENFig.3Knowledgerepresentationofthetransmissionpartstogetacertainconstraintrelations.ForexamplethemathematicalformulaofwormallowablecontactstressissHPHPvNZZσσandstresscyclesequationis160LhNntγ.2ClassrulesTheknowledgedrivenmodelbehindknowledgebasedengineeringKBEisbasedonalanguagetailoredforcapturingengineeringrules.Ifthewormheadisequalto1,theestimatedrangeofefficiencyis0.65to0.75whenthewormheadisequalto2,theefficiencyoftherangeof0.75085whenthewormheadisgreaterthan2,theeffectiverange0.85.Iftheconditionpartissatisfied,thentheconclusionpartDecember2010TheResearchofIndependentKnowledgeBasedMechanicalDesign3isexecuted.ThesampleofwormgearclassruleexpressionisasfollowsIfworm_z1{Efficiency0.650.75}Ifworm_z2{Efficiency0.750.85}Ifworm_z2{Efficiency0.85}3DesigntablesTherearemanyengineeringknowledgeofstandardpartsoftenexistsintableform,Fig.4isatableoftherelationshipofmodule,wormdiameterandwormdiameterfactorwhichisusedtodeterminedimensionalfamiliesofproduct.Fig.4TherelationshipofmoduleanddiameterTabledataarediscretebinarymappingthatcanbestoreinarelationaldatabaseaccordingtocertainrulesusingascriptinglanguage.Thisscriptinglanguagerelatedtosyntaxandlanguageinterpretertoexplainthemappingtable,representtousetheform.4ExpertiseExpertiseplaystheroletofilltheknowledgegapbetweenthedetailstageandtheconceptualstage,assistthedesignerstomakedecision.Forexample,expertisetellswhichworkingtemperaturerangeshouldbemoreeligible,higherthan95℃orlessthan95℃.5ParametricmodelParametricmodelfilessuchasUG.Prtfilestorethehistoryofproductmodeling,modelingprocesscontainthecarrierofexpertiseandknowledge.Parametricmodelprovidestheknowledgemodelingprocess.Thereforegeometricmodelcanbechangequickly,canbeviewedasaninstanceofaclassofgeometricmodelsObjectorientedmethodcanbeusedtoorganizeandexpressthisknowledge.Forexample,thedesignofthewormgeometricmodelhasseveralgeometricparametersasshowninTable1.Table1WormmodelinggeometryModulemPitchcirclediameterdAddendumcirclediameterd1Toothrootdiameterd2PressureangleaLengthL6ChartChartisacommonengineeringknowledgeexpresswithtwodimensionalcoordinatedsysteminwhichthedataisrepresentedbysymbols,suchasbarsinabarchart,linesinalinechartandsoon.Thereforeknowledgeisimplementedinvariousformsincludingengineeringrules,formulas,geometricmodels,designtablesandchartstoconstructindependentknowledgebasedsystem.Italsodescribestherepresentationofgeometricpropertiesincludingpartcomplexityandtheautomationofthedesignprocesses.4IndependentKnowledgeBasedDesignArchitectureMechanicaldesignengineersarealwaysfacedwiththeproblemtogetthecorrectgeometricinformation,parametersandneedtofindnongeometricfeatureinformationfromthemechanicaldesignhandbookmanually.Informationisdifficulttocommunicateverballyandformalizeforthepurposeofdesigningaknowledgebase7.Knowledgeinterpretercanbesolvedtheseproblems.KnowledgeInterpreterKIisconstructedbasedonknowledgerepresentationexplainedinsection3togetparametricmodelthatmeanknowledgedrivenparametricmodel.TheprinciplestructureofknowledgeinterpreterKIisshowninFig.5.Knowledgeinterpretercanparse4PHYOWaiLin,XIPing,ZHANGBaoyuan,CHENRuizhiCADDM

注意事项

本文(外文翻译--基于知识的机械设计独立研究 英文版.pdf)为本站会员(英文资料库)主动上传,人人文库网仅提供信息存储空间,仅对用户上传内容的表现方式做保护处理,对上载内容本身不做任何修改或编辑。 若此文所含内容侵犯了您的版权或隐私,请立即通知人人文库网(发送邮件至[email protected]或直接QQ联系客服),我们立即给予删除!

温馨提示:如果因为网速或其他原因下载失败请重新下载,重复下载不扣分。

[email protected] 2015-2017 人人文库网网站版权所有
苏ICP备12009002号-5