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GSELIGERETALEDS,ADVANCESINSUSTAINABLEMANUFACTURINGPROCEEDINGSOFTHE8THGLOBALCONFERENCE149ONSUSTAINABLEMANUFACTURING,DOI101007/9783642201837_22,SPRINGERVERLAGBERLINHEIDELBERG2011METHODOLOGYFORHIGHACCURACYINSTALLATIONOFSUSTAINABLEJIGSANDFIXTURESJJAMSHIDI,PGMAROPOULOSDEPARTMENTOFMECHANICALENGINEERING,UNIVERSITYOFBATH,UKABSTRACTTHEABILITYTOACCURATELYMEASURETHECOMPONENTSOFJIGSANDFIXTURESDURINGTHEIRINSTALLATIONDETERMINESTHESTATEOFTHEIRPRECISION,ESPECIALLYFORLARGESIZEPRODUCTSANDAPPLICATIONSTHISMATTERISCRUCIALINMASSCUSTOMISATIONWHERESMALLBATCHESOFPRODUCTSANDCOMPONENTSWITHHIGHVARIETYINDESIGNAREMANUFACTUREDPRODUCTQUALITYSHOULDBEINHARMONYWITHRAPIDCHANGEOVERPHILOSOPHYASCOMPROMISINGQUALITYFORSPEEDISNOTFORGIVABLEFORSENSITIVECOMPONENTSANDASSEMBLIESSUCHASTHOSESEENINTHEAEROSPACEINDUSTRYITISNECESSARYFORTHEINSTALLATIONOFTHEJIGSANDFIXTURESTOBEHIGHLYACCURATEINORDERTOMINIMISETHEUSEOFTOLERANCEBUDGETDUETOVARIATIONSINJIGSANDFIXTUREPOSITIONINGMAJOROVERHEADCOSTSFORJIGSANDFIXTURESPARTICULARLYINTHEAEROSPACEINDUSTRYLEDTOTHEDEVELOPMENTOFTHECONCEPTOFFLEXIBLEANDRECONFIGURABLEJIGSANDFIXTURESREUSABILITYOFRECONFIGURABLEJIGSANDFIXTURESMAKESTHEMATTRACTIVEFORSUSTAINABLESOLUTIONSASTHEIRCOMPONENTSCANBEREUSEDFORSEVERALVARIANTOFAPRODUCTORASSEMBLYTHEMAINDRAWBACKSOFTHISTYPEOFJIGSANDFIXTURESHAVEBEENTHEIRPOORACCURACYANDRELIABILITYINTHISPAPERACCURATEPOSITIONINGOFTHEKEYCOMPONENTSOFSUSTAINABLEJIGSANDFIXTURESISINVESTIGATEDTHEFACTORSAFFECTINGTHEPERFORMANCEOFTHEJIGSANDFIXTURESAREREVIEWEDFROMTHEINSTALLATIONSTAGETHEPAPERINTRODUCESAMETHODOLOGYFORMINIMISINGUNCERTAINTIESINPOSITIONINGOFTHEHOLDSANDCLAMPSFORFLEXIBLEJIGSANDFIXTURESKEYWORDSSUSTAINABLEJIG,JIGINSTALLATION,CALIBRATIONUNCERTAINTY,JIGMONITORING,METROLOGY,REUSABLEJIG1INTRODUCTIONFACTORSSUCHASQUALITYANDRELIABILITYHAVELONGCONVERTEDTOIMPLICITCHARACTERISTICSOFTHENEWPRODUCTSRECENTMARKETTRENDSHAVEFORCEDMANUFACTURINGINDUSTRIESTOMOVETOWARDSMASSCUSTOMISATIONINTHEIRPRODUCTSANDSERVICERANGEINCREASEDVARIATIONINTHEDESIGNOFNEWPRODUCTSISFOLLOWEDBYASECONDWAVEOFVARIATIONWITHHIGHERAMPLITUDEATSUBASSEMBLIESANDCOMPONENTLEVELSTATEOFTHEARTMANUFACTURINGSYSTEMSANDTECHNOLOGIESHAVEPROVIDEDMOREFLEXIBILITY,ENABLINGDESIGNERSTOTHINKMOREFREELYFORINSTANCENEWLARGEVOLUMEMEASUREMENTSYSTEMS,DEVELOPEDINTHEPASTFEWYEARS,ARECAPABLEOFMEASURINGSEVERALDECAMETREDISTANCESSUCHTECHNOLOGIESFACILITATETHEVERIFICATIONOFLARGESIZECOMPONENTSTHATUSEDTOBEMANUFACTUREDFROMSEVERALASSEMBLEDCOMPONENTSTHEMANUFACTURINGOFLARGESIZEPRODUCTSREQUIRESSPECIALISTJIGSANDFIXTURESINORDERFORTHEIRCOMPONENTSTOBEHELDINTHEDESIREDORIENTATIONDURINGBUILDANDASSEMBLYTHISREQUIRESMAJOROVERHEADCOSTTHATCANONLYBEJUSTIFIEDBYMASSPRODUCTIONINSOMECASESOROTHERWISETHECOSTOFFINISHEDPRODUCTSCANBEVERYHIGHTHISISSUECONTRADICTSWITHTHEMARKETTRENDSWHERECUSTOMERSARECONSTANTLYLOOKINGFORHIGHERVALUEFORTHEIRMONEYINATYPICALPRODUCTTHEVARIATIONINTHEPRODUCTCREATESAMORESUSTAINABLEBUSINESSASITCANFULFILTHENEEDSOFARELATIVELYLARGERMARKETFLEXIBLEANDRECONFIGURABLEJIGSANDFIXTURETHATCANBEFORMEDINDIFFERENTSHAPESTOSUPPORTDIFFERENTVARIATIONOFPRODUCTSISAKEYSOLUTIONFORTHEABOVECHALLENGESTHECONCEPTOFFLEXIBLEJIGEXISTEDFORSEVERALYEARSINTHERESEARCHDOMAIN1HOWEVER,THEYARENOTFULLYUTILISEDTOAGREATEXTENTINREALPRODUCTIONFACILITIESESPECIALLYFORLARGESIZEPRODUCTMANUFACTURERS,SUCHASAEROSPACETHISISDUETOTHECHALLENGESRELATEDTOTHEIRINITIALINSTALLATION,POORCALIBRATION,ANDREPEATABILITYTHATOFTENEXCEEDTHETOLERANCEREQUIREMENTTHEMANUFACTURINGOFTHESEJIGSANDFIXTURESFROMHIGHQUALITYKEYCOMPONENTSASWELLASTHEIRINTEGRATIONWITHLARGEVOLUMEMETROLOGYSYSTEMSCANREDUCETHEABOVELIMITATIONSTHISPAPERCOVERSMETROLOGYISSUESRELATEDTOTHEINSTALLATIONANDCALIBRATIONOFFLEXIBLEJIGSANDFIXTURESASWELLASTHEIRMONITORINGDURINGSERVICE2RELATEDWORK21MANUFACTURINGANDASSEMBLYOFLARGESCALEPARTSTYPICALLYPRIORTOPRECISIONMANUFACTURINGOFMECHANICALPARTSITISESSENTIALTOMOVETHERAWMATERIALTOTHEMACHINEBENCH,PROCEEDWITHROUGHCUTTINGTHENFINEALIGNMENTANDCLAMPINGATTHISSTAGETHEPARTISREADYFORMACHININGOFITSHIGHPRECISIONKEYFEATURESHOWEVER,THISISNOTALWAYSPOSSIBLEFORLARGESIZEAND/ORHEAVYCOMPONENTSLARGESCALEPRODUCTSREFERTOTHOSEWITHCOMPONENTSTHATARENOTECONOMICALLYPOSSIBLETOHANDLEORMOVEAROUNDINTHEFACTORYFORFABRICATIONANDASSEMBLYPURPOSES2THEMANUFACTURINGANDASSEMBLYPROCESSESOFTHESEPARTSENCOMPASSMOVEMENTOFTHEMACHINESANDSYSTEMSTOTHEDESIREDLOCATIONANDORIENTATIONWITHRESPECTTOTHESEPARTSSUCHPARTSARENORMALLYHELDINTHEIRPOSITIONSUSINGLARGESIZEJIGSANDFIXTURESIFTHESEPARTSAREPRODUCEDINSMALLBATCHSIZESTHATISTHECASEFORAEROSPACEINDUSTRIES,HIGHOVERHEADCOSTPERPRODUCTWILLOCCURTHEREHAVEBEENMANYATTEMPTSTODESIGNANDMANUFACTUREJIGSANDFIXTURESSOTHATTHEYCANHOLDANUMBEROFVARIANTSOFCOMPONENTS3,4HOWEVER,THISAPPROACHISNOTFEASIBLEFORPARTSWITHSENSITIVEORKEYFEATURESDUETOTHEIRHIGHACCURACYREQUIREMENTSJJAMSHIDI,PGMAROPOULOS150ADJUSTABLE,RECONFIGURABLEJIGSANDFIXTURESPRODUCELOWERREPEATABILITYOVERTIMECOMPAREDTOFIXEDONESFIXEDJIGSHAVEPERMANENTTOPOLOGYACHIEVEDTHROUGHTHEIRPERMANENTJOINTSTHATAREWELDEDORRIVETEDMECHANICALFAILUREOFTHESEJIGSANDFIXTURESFOREXAMPLEDUETOFATIGUEANDPLASTICDEFORMATIONISAMAINCAUSEOFTERMINATINGTHEIRSERVICEANDSENDINGTHEMFORRECYCLINGWITHSMALLBATCHMANUF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