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51AutomatedStorage/RetrievalSystemsUNIT4AUTOMATEDSTORAGE/RETRIEVALSYSTEMSStructure4.1IntroductionObjectives4.2FunctionsofStorageSystemandDefinitionofAS/RS4.3AS/RSComponentsandTerminology4.4TypesofAS/RS4.5DesignofanAS/RS4.5.1LoadSizesDetermination4.5.2CalculatingIndividualStorageSpaceDimensions4.5.3EstimatingStorageSpacesNumber4.5.4EstimationofAS/RSThroughputandtheNumberofS/RMachines4.5.5EstimatingtheSizeParametersoftheStorageandRetrievalSystem4.5.6DeterminationofSingle-andDual-commandCycleTimesforUnitLoadAS/RS4.5.7EstimatingtheUtilizationofS/RMachines4.6Summary4.7KeyWords4.1INTRODUCTIONImagineanyplant/manufacturingsectorwithoutclutteredaisles,excessinventory,lostordamagedproducts,inaccuraterecords,endlesssearching,climbing,bendingandfrustration.Imagineahighlyprofitableoperationthataddsvalueanddecreasesexpense.AS/RSaremeanstohighdensityhandsfreebufferingofmaterialsindistributionandmanufacturingenvironments.AS/RSisacompletesystemdesignedtotransport,stage/store,retrieve,andreportoneveryiteminanyindustrialinventorywithup-to-theminuteaccuracy.ObjectivesAfterstudyingthisunit,youshouldbeabletounderstandtheAS/RSinacomputer-integratedmanufacturingsystem,anddesignaspectsofAS/RS.4.2FUNCTIONSOFSTORAGESYSTEMANDDEFINITIONOFAS/RSAnautomatedstorage/retrievalsystem(AS/RS)canbedefinedasastoragesystemunderwhichadefineddegreeofautomationistobeimplementedtoensureprecisionaccuracyandspeedinperformingstorageandretrievaloperations.Theseautomatedstorageandmechanizedsystemseliminatehumaninterventioninperformingbasicsetsofoperationsthatincludes:RemovalofanitemfromastoragelocationautomaticallyTransferringtheaboveitemtoaspecificprocessingorinterfacepointAfterreceivinganitemfromaprocessingorinterfacepoint,itisautomaticallystoredatapredeterminedlocation.52ComputerIntegratedManufacturingAlistofpossibleobjectivesthatacompanymaywanttoachievebyinstallinganautomatedstoragesystemispresentedinTable4.1.Table4.1:ObjectivesforInstallinganAutomatedStorageSysteminaFactoryIncreasingthestoragecapacityIncreasingthestockrotationUtilizationofmaximumfloorspaceRecoveringthespaceformanufacturingfacilitiesCustomerservicetobeimprovedControloverinventoriestobeimprovedEnsuringsafetyinstoragefunctionIncreasingthelabourproductivityinstoragefunctionReducinglabourcostinstorageoperationReducingpilferageandimprovingsecuritySource:Basedonlistinreference[4]4.3AS/RSCOMPONENTSANDTERMINOLOGYAnAS/RSconsistsofoneormorestorageaislesthatareservicedbyastorage/retrieval(S/R)machine.Thestoredmaterialsareheldbystorageracksofaisles.TheS/Rmachinesareusedtodeliverandretrievematerialsinandoutofinventory.Thereareoneormoreinput/outputstationsineachAS/RSaislefordeliveringthematerialintothestoragesystemormovingitoutofthesystem.InAS/RSterminology,theinput/outputstationsarecalledpickup-and-deposit(P&D)stations.ThecomponentsindicatedinFigure4.1arebrieflyexplainedbelow.Figure4.1:GenericStructureofasAS/RSAisleunitAisleRackwidthRowBayRackheightStorageracksStoragespaceStorageracksRacklengthStacker(S/R)machineClearanceforP/DareaWidthofAS/RS53AutomatedStorage/RetrievalSystemsStorageSpaceItisthethree-dimensionalspaceinthestorageracksusedtostoreasingleloadunitofmaterial.StorageRacksThisstructuralentitycomprisesstoragelocations,baysandrows.BayItistheheightofthestoragerackfromfloortotheceiling.RowItisaseriesofbaysplacedsidebyside.AisleItisthespacingbetw...