ApplicationanddevelopmentOfcasebasedreasoninginfixturedesignAbstract:Basedonthecasebaseddesigning(CBD)methodology,thefixturesimilarityisintworespects:thefunctionandthestructureinformation.Then,thecomputeraidedfixturedesignsystemiscreatedoncasebasedreasoning(CBR),inwhichtheattributesofthemainfeaturesofworkpieceandstructureoffixtureascaseindexcodearedesignedfortheretrieveofthesimilarcases,andthestructureandhierarchicalrelationofcaselibraryaresetupforstore.Meanwhile,thealgorithmbasedontheknowledgeguidedintheretrieveofthesimilarcases,thestrategyofcaseadaptationandcasestorageinwhichthecaseidentifcationnumberisusedtodistinguishfromsimilarcasesarepresented.Theapplicationofthesysteminsomeprojectsimprovesthedesignefficiencyandgetsagoodresult.Keywords:casebasedreasoning;fixturedesign;computeraideddesign(CAD)Fixturesaredevicesthatserveasthepurposeofholdingtheworkpiecesecurelyandaccurately,andmaintainingaconsistentrelationshipwithrespecttothetoolswhilemachining.Becausethefixturestructuredependsonthefeatureoftheproductandthestatusoftheprocessplanningintheenterprise,itsdesignisthebottleneckduringmanufacturing,whichrestrainstoimprovetheefficiencyandleadtime.Andfixturedesignisacomplicatedprocess,basedonexperiencethatneedscomprehensivequalitativeknowledgeaboutanumberofdesignissuesincludingworkpiececonfiguration,manufacturingprocessesinvolved,andmachiningenvironment.ThisisalsoaverytimeconsumingworkwhenusingtraditionalCADtools(suchasUnigraphics,CATIAorPro/E),whicharegoodatperformingdetaileddesigntasks,butprovidefewbenefitsfortakingadvantageofthepreviousdesignexperienceandresources,whicharepreciselythekeyfactorsinimprovingtheefficiency.Themethodologyofcasebasedreasoning(CBR)adaptsthesolutionofapreviouslysolvedcasetobuildasolutionforanewproblemwiththefollowingfoursteps:retrieve,reuse,revise,andretain[1].Thisisamoreusefulmethodthantheuseofanexpertsystemtosimulatehumanthoughtbecauseproposingasimilarcaseandapplyingafewmodificationsseemstobeselfexplanatoryandmoreintuitivetohum