lecture 25 flexible manufacturing systems [compatibility mode]

ME-418 CAD/CAM

Lecture #: 25

Flexible Manufacturing Systems

Ref: Groover (Chap – 16)

Faculty of Mechanical Engineering

Ghulam Ishaq Khan Institute of Engineering Sciences & Technology, Pakistan

Lecture By: Muftooh Ur Rehman SiddiqiResearch Associate

Office # G-17Email: [email protected]

Flexible Manufacturing System (FMS)Flexible Manufacturing System (FMS)

ItIt isis thethe mostmost automatedautomated andand technologytechnology sophisticatedsophisticated ofof thethe GTGTcellscells..

An FMS integrates into one highly automated An FMS integrates into one highly automated manufacturing systems including flexible automation, manufacturing systems including flexible automation,

CNC machines, distributed computer control, CNC machines, distributed computer control,

© Muftooh Ur Rehman Siddiqi, FME GIK Institute, Pakistan 2 of 32

CNC machines, distributed computer control, CNC machines, distributed computer control, automated material handling and storage and group automated material handling and storage and group

technology.technology.

Reasons for Automation


Prod. Variety and Qty. for Diff. Automation

FMS lies here


History of FMSHistory of FMS

�� TheThe FMSFMS waswas firstfirst conceptualizedconceptualized forfor machining,machining, andand ititrequiredrequired thethe priorprior developmentdevelopment ofof NCNC..

�� ThisThis conceptconcept isis creditedcredited toto DavidDavid Williamson,Williamson, aa BritishBritishengineerengineer duringduring midmid--19601960ss..

�� InIn latelate 19601960ss thethe firstfirst FMSFMS machiningmachining systemsystem waswas installedinstalled atatIngersollIngersoll--RandRand companycompany inin VirginiaVirginia.. OtherOther companiescompanies likelike


IngersollIngersoll--RandRand companycompany inin VirginiaVirginia.. OtherOther companiescompanies likelikeCaterpillar,Caterpillar, CincinnatiCincinnati MilacronMilacron andand GeneralGeneral ElectricElectric followedfolloweditit..

�� GermanyGermany implementedimplemented itsits firstfirst FMSFMS inin 19691969,, inin cooperationcooperationwithwith thethe universityuniversity ofof StuttgartStuttgart..

�� RussiaRussia andand JapanJapan implementedimplemented FMSFMS inin 19721972..

What is an FMS?What is an FMS?

�� AA FMSFMS isis aa highlyhighly automatedautomated GTGT machinemachine cellcell,, consistingconsisting ofof aa

groupgroup ofof processingprocessing workstationsworkstations (usually(usually CNCCNC machinemachine tools),tools),

interconnectedinterconnected byby anan automatedautomated materialmaterial handlinghandling andand storagestorage

systemsystem andand controlledcontrolled byby aa distributeddistributed computercomputer systemsystem..

�� TheThe reasonreason thethe FMSFMS isis flexibleflexible isis thatthat itit isis capablecapable ofof

processingprocessing aa varietyvariety ofof differentdifferent partpart stylesstyles simultaneouslysimultaneously atat


processingprocessing aa varietyvariety ofof differentdifferent partpart stylesstyles simultaneouslysimultaneously atat

thethe variousvarious workstationworkstation andand thethe mixmix ofof partpart stylesstyles andand

quantitiesquantities ofof productionproduction cancan bebe adjustedadjusted inin responseresponse toto

changingchanging demanddemand patternspatterns..

What is an FMS? (contd…)What is an FMS? (contd…)

�� TheThe FMSFMS isis mostmost suitedsuited forfor thethe midmid--variety,variety, midmid--volumevolumeproductionproduction rangerange..

�� TheThe machiningmachining processprocess isis presentlypresently thethe largestlargest applicationapplication areaarea

forfor FMSFMS technologytechnology..

�� AnAn FMSFMS reliesrelies onon thethe principleprinciple pfpf groupgroup technologytechnology..


�� HoweverHowever nono manufacturingmanufacturing systemsystem cancan bebe completelycompletely flexibleflexible..

ThereThere isis aa limitlimit toto thethe rangesranges ofof partsparts oror productsproducts thatthat cancan bebe

mademade inin FMSFMS.. InIn otherother wordswords FMSFMS isis designeddesigned toto produceproduce aa

singlesingle partpart familyfamily oror limitedlimited rangerange ofof partpart familiesfamilies..

Required Conditions to Implement FMSRequired Conditions to Implement FMS

�� Presently,Presently, thethe plantplant eithereither ((11)) producesproduces partsparts inin batchesbatches oror ((22))

usesuses mannedmanned GTGT cellscells andand managementmanagement wantwant toto automateautomate..

�� ItIt mustmust bebe possiblepossible toto groupgroup aa portionportion ofof thethe partsparts mademade inin thethe

plantplant intointo partpart familiesfamilies,, whosewhose similaritiessimilarities permitpermit themthem toto bebe

processedprocessed onon thethe machinesmachines inin thethe FMSFMS.. SimilaritiesSimilarities cancan eithereither

bebe designdesign oror manufacturingmanufacturing attributesattributes..


bebe designdesign oror manufacturingmanufacturing attributesattributes..

�� TheThe partsparts oror productsproducts mademade byby thethe facilityfacility areare inin thethe midmid--

volume,volume, midmid--varietyvariety productionproduction rangerange..

Characteristics of FMSCharacteristics of FMS

TheThe differencedifference betweenbetween implementingimplementing aa manuallymanually operatedoperated

machinemachine cellcell andand installinginstalling anan FMSFMS areare::

11.. FMSFMS requiresrequires aa significantlysignificantly greatergreater capitalcapital investmentinvestment

becausebecause newnew equipmentequipment isis beingbeing installedinstalled ratherrather thanthan existingexisting

equipmentequipment beingbeing rearrangedrearranged..


22.. TheThe FMSFMS isis technologicallytechnologically moremore sophisticatedsophisticated forfor thethe humanhuman

resourcesresources whowho mustmust makemake itit..

What Makes it Flexible?What Makes it Flexible?

FollowingFollowing areare thethe threethree capabilitiescapabilities thatthat aa manufacturingmanufacturing systemsystemmustmust possesposses toto bebe flexibleflexible::

11.. TheThe abilityability toto identifyidentify andand distinguishdistinguish amongamong thethe differentdifferentpartsparts oror productproduct stylesstyles processedprocessed byby thethe systemsystem..

22.. QuickQuick changeoverchangeover ofof operatingoperating instructionsinstructions..


22.. QuickQuick changeoverchangeover ofof operatingoperating instructionsinstructions..

33.. QuickQuick changeoverchangeover ofof physicalphysical setupsetup..

FlexibilityFlexibility isis anan attributeattribute thatthat appliesapplies toto bothboth manualmanual andandautomatedautomated systemssystems..

Criteria for FMS Criteria for FMS

ToTo qualifyqualify asas beingbeing FMS,FMS, aa manufacturingmanufacturing systemssystems shouldshould satisfysatisfyfollowingfollowing criteriacriteria inin anan automatedautomated manufacturingmanufacturing systemsystem..

�� PartPart varietyvariety testtest.. AnAn thethe systemsystem processprocess differentdifferent partpart stylesstyles ininaa nonnon--batchbatch model?model?

�� ScheduleSchedule changechange testtest.. CanCan thethe systemsystem readilyreadily acceptaccept changeschanges ininproductionproduction scheduleschedule andand changeschanges inin eithereither partpart mixmix ororproductionproduction quantities?quantities?


productionproduction quantities?quantities?

�� ErrorError recoveryrecovery testtest.. CanCan thethe systemsystem recoverrecover gracefullygracefully fromfromequipmentequipment malfunctionsmalfunctions andand breakdowns,breakdowns, soso thatthat productionproductionisis notnot completelycompletely disrupted?disrupted?

�� NewNew partpart testtest.. CanCan newnew partpart designsdesigns bebe introducedintroduced intointo thetheexistingexisting productproduct mixmix withwith relativerelative easeease..

Types of FMSTypes of FMS

FMSFMS isis designeddesigned forfor aa specificspecific application,application, thatthat isis aa specificspecific familyfamilyofof partsparts andand processesprocesses.. ThereforeTherefore eacheach FMSFMS isis customcustomengineered,engineered, eacheach FMSFMS isis uniqueunique..

FMSFMS cancan bebe distinguisheddistinguished accordingaccording toto thethe kindkind ofof manufacturingmanufacturingoperationsoperations theythey performperform

11.. ProcessingProcessing operationsoperations


22.. AssemblyAssembly operationsoperations

FMSFMS cancan alsoalso bebe classifiedclassified byby

11.. NumberNumber ofof machinesmachines..

22.. LevelLevel ofof FlexibilityFlexibility

Number of MachinesNumber of Machines

FMSFMS cancan bebe distinguisheddistinguished accordingaccording toto thethe numbernumber ofof machinesmachinesinin thethe systemsystem.. TheThe followingfollowing areare thethe typicaltypical categoriescategories::

SingleSingle machinemachine cellcell (SMC)(SMC) consistsconsists ofof oneone CNCCNC machiningmachining centercentercombinedcombined withwith aa partsparts storagestorage systemsystem forfor unattendedunattended operationoperation..

FlexibleFlexible machinemachine cellcell (FMC)(FMC) consistsconsists ofof twotwo oror threethree processingprocessingworkstationsworkstations (typically(typically CNCCNC machiningmachining oror turningturning centers)centers) plusplus aa


workstationsworkstations (typically(typically CNCCNC machiningmachining oror turningturning centers)centers) plusplus aapartpart handlinghandling systemsystem.. TheThe partpart handlinghandling systemsystem isis connectedconnected toto aaload/unloadload/unload stationstation..

FlexibleFlexible manufacturingmanufacturing systemsystem (FMS)(FMS) hashas fourfour oror moremoreprocessingprocessing workstationworkstation connectionconnection mechanicallymechanically byby aa commoncommonpartpart handlinghandling systemssystems andand electronicallyelectronically byby aa distributeddistributedcomputercomputer systemsystem..

Number of MachinesNumber of Machines


Difference b/w FMC and FMSDifference b/w FMC and FMS

AnAn importantimportant distinctiondistinction b/wb/w FMCFMC andand FMSFMS isis thethe numbernumber ofofmachinesmachines:: anan FMCFMC hashas twotwo oror threethree m/c,m/c, whilewhile FMSFMS hashas fourfour orormoremore..

FMSFMS generallygenerally includesincludes nonnon--processingprocessing workwork--stationsstations likelikeCoordinateCoordinate MeasuringMeasuring MachineMachine (CMM)(CMM) thatthat supportsupport productionproductionbutbut dodo notnot directlydirectly participateparticipate inin itit..


TheThe computercomputer controlcontrol systemsystem ofof FMSFMS isis generallygenerally largerlarger andandmoremore sophisticated,sophisticated, suchsuch asas diagnosticsdiagnostics andand tooltool monitoringmonitoring..

Level of FlexibilityLevel of Flexibility

AnotherAnother classificationclassification ofof FMSFMS isis accordingaccording toto thethe levellevel ofofflexibilityflexibility designeddesigned intointo thethe systemsystem..

DedicatedDedicated FMSFMS isis designeddesigned toto produceproduce aa limitedlimited varietyvariety ofof partspartsstyles,styles, andand thethe completecomplete universeuniverse oo partsparts toto bebe mademade onon thethesystemsystem isis knownknown inin advancesadvances.. TheThe termterm specialspecial manufacturingmanufacturingsystemsystem hashas alsoalso beenbeen usedused inin referencereference toto thisthis FMSFMS typetype..


RandomRandom--orderorder FMSFMS isis moremore appropriateappropriate whenwhen thethe partpart familyfamily isislarge,large, therethere areare substantialsubstantial variationsvariations inin partpart configurations,configurations,therethere willwill bebe newnew partpart designsdesigns introducedintroduced intointo thethe systemsystem andandengineeringengineering changeschanges inin partsparts currentlycurrently produced,produced, andand thetheproductionproduction scheduledscheduled isis subjectsubject toto changechange fromfrom dayday toto dayday..

Level of Flexibility (contd…)Level of Flexibility (contd…)

ThereThere isis aa tradetrade--offoff b/wb/w thethe flexibilityflexibility andand productivityproductivity inin thethe twotwotypestypes ofof systemsystem..

TheThe dedicateddedicated FMSFMS isis lessless flexibleflexible butbut moremore capablecapable ofof higherhigherproductionproduction ratesrates..

TheThe randomrandom orderorder FMSFMS isis moremore flexibleflexible butbut atat thethe proceproce ofof lowerlowerproductionproduction ratesrates..


productionproduction ratesrates..

Dedicated FMS

Random Order FMS

Production rate

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FMS ComponentsFMS Components

FollowingFollowing areare thethe basicbasic componentscomponents ofof anan FMSFMS

�� WorkstationsWorkstations

�� MaterialMaterial HandlingHandling andand storagestorage systemssystems

�� ComputerComputer controlcontrol systemsystem

�� Even,Even, thoughthough itit isis highlyhighly automated,automated, peoplepeople areare requiredrequired totooperateoperate thethe systemsystem..


operateoperate thethe systemsystem..

AllAll thesethese componentscomponents areare discusseddiscussed inin thethe followingfollowing slidesslides..

WorkstationsWorkstations

FollowingFollowing areare thethe typestypes ofof workstationworkstation typicallytypically foundfound inin anan FMSFMS

�� Load/UnloadLoad/Unload stationsstations

�� MachiningMachining StationsStations

�� OtherOther ProcessingProcessing StationsStations


�� AssemblyAssembly

�� OtherOther StationsStations andand EquipmentEquipment..

Material Handling and Storage SystemMaterial Handling and Storage SystemTheThe secondsecond majormajor componentcomponent ofof anan FMSFMS isis itsits materialmaterial handinghandingandand storagestorage systemsystem..

�� FunctionFunction ofof thethe materialmaterial handlinghandling systemsystem

�� Random,Random, independentindependent movementmovement ofof workwork partsparts b/wb/w stationsstations..

�� HandleHandle aa varietyvariety ofof workwork partpart configurationsconfigurations

�� TemporaryTemporary storagestorage


�� TemporaryTemporary storagestorage

�� CompatibleCompatible withwith computercomputer controlcontrol

FMS Layout ConfigurationsFMS Layout ConfigurationsTheThe materialmaterial handlinghandling systemsystem establishesestablishes thethe FMSFMS layoutlayout.. ThereThereareare::

InlineInline layoutlayout,, thethe machinesmachines andand handlinghandling systemsystem areare arrangedarranged ininaa straightstraight lineline.. InIn itsits simplestsimplest form,form, thethe partsparts progressprogress fromfrom oneoneworkstationworkstation toto thethe nestnest inin aa wellwell defineddefined sequence,sequence, withwith workworkalwaysalways movingmoving inin oneone directiondirection andand nono backback flowflow..

LoopLoop layoutlayout,, thethe workstationsworkstations areare organizedorganized inin aa looploop thatthat isis


LoopLoop layoutlayout,, thethe workstationsworkstations areare organizedorganized inin aa looploop thatthat isisservedserved byby aa partpart handlinghandling systemsystem.. PartsParts usuallyusually flowflow inin oneonedirectiondirection aroundaround thethe loop,loop, withwith capabilitycapability toto stopstop andand bebetransferredtransferred toto anyany stationstation.. AnAn alternativealternative formform ofof looploop layoutlayout isisthethe rectangularrectangular layoutlayout..

FMS Layout ConfigurationsFMS Layout ConfigurationsTheThe ladderladder layoutlayout consistsconsists ofof aa looploop withwith rungsrungs b/wb/w thethe straightstraightsectionssections ofof thethe loop,loop, onon whichwhich workstationworkstation areare locatedlocated.. TheThe rungsrungsincreaseincrease thethe possiblepossible waysways ofof gettinggetting fromfrom oneone machinemachine toto thethenextnext.. ThisThis reducesreduces averageaverage traveltravel distancedistance andand therebythereby reducingreducingtransporttransport timetime b/wb/w workstationsworkstations..

TheThe openopen fieldfield layoutlayout consistsconsists ofof multiplemultiple loopsloops andand laddersladders andandmaymay includeinclude sidingssidings asas wellwell.. ThisThis typetype layoutlayout isis generallygenerally


maymay includeinclude sidingssidings asas wellwell.. ThisThis typetype layoutlayout isis generallygenerallyappropriateappropriate forfor processingprocessing largelarge familyfamily ofof partsparts..

TheThe robotrobot centeredcentered cellcell usesuses oneone oror moremore robotsrobots asas thethe materialmaterialhandlinghandling systemsystem.. IndustrialIndustrial robotsrobots cancan bebe equippedequipped withwith grippersgrippersthatthat makemake themthem wellwell suitedsuited forfor handlinghandling ofof rotationalrotational partsparts..

Computer Control SystemComputer Control SystemFunctionsFunctions performedperformed byby thethe FMSFMS computercomputer controlcontrol systemsystem::

�� WorkstationWorkstation controlcontrol

�� DistributionDistribution ofof controlcontrol instructioninstruction toto workstationsworkstations

�� ProductionProduction controlcontrol

�� TrafficTraffic controlcontrol

�� ShuttleShuttle controlcontrol


�� ShuttleShuttle controlcontrol

�� WorkWork piecepiece monitoringmonitoring

�� ToolTool controlcontrol -- (a)(a) ToolTool locationlocation (b)(b) ToolTool lifelife monitoringmonitoring

�� PerformancePerformance monitoringmonitoring andand reportingreporting

�� DiagnosticsDiagnostics

Human ResourcesHuman ResourcesOneOne additionaladditional componentscomponents inin thethe FMSFMS isis humanhuman labourlabour..HumansHumans areare neededneeded toto managemanage thethe operationsoperations ofof thethe FMSFMS..FunctionsFunctions typicallytypically performedperformed byby humanshumans includeinclude::

11.. LoadingLoading rawraw workwork partsparts intointo thethe systemsystem..

22.. UnloadingUnloading finishedfinished partsparts (or(or assemblies)assemblies) fromfrom thethe systemsystem..

33.. ChangingChanging andand settingsetting toolstools..


44.. EquipmentEquipment maintenancemaintenance andand repairrepair..

55.. NCNC partpart programmingprogramming inin aa machiningmachining systemsystem..

66.. ProgrammingProgramming andand operatingoperating thethe computercomputer systemsystem..

77.. OverallOverall managementmanagement ofof thethe systemsystem..

FMS ApplicationsFMS Applications

Self study from book, ‘Automation, Production Self study from book, ‘Automation, Production Systems and Computer integrated Systems and Computer integrated

Manufacturing’, Chapter 16, Page 480~484.Manufacturing’, Chapter 16, Page 480~484.


Manufacturing’, Chapter 16, Page 480~484.Manufacturing’, Chapter 16, Page 480~484.

Benefits of FMSBenefits of FMS

TheThe benefitsbenefits thatthat cancan bebe expectedexpected fromfrom anan FNSFNS includeinclude::

�� IncreaseIncrease machinemachine utilizationutilization

�� FewerFewer machinemachine requiredrequired

�� ReductionReduction inin factoryfactory floorfloor spacespace requiredrequired

�� GreaterGreater responsivenessresponsiveness toto changechange..

ReducedReduced inventoryinventory requirementsrequirements


�� ReducedReduced inventoryinventory requirementsrequirements

�� LowerLower manufacturingmanufacturing leadlead timestimes..

�� ReducedReduced directdirect laborlabor requirementrequirement andand higherhigher productivityproductivity..

FMS Planning and ImplementationFMS Planning and ImplementationImplementationImplementation ofof anan FMSFMS representsrepresents aa majormajor investmentinvestment andandcommitmentcommitment byby thethe useruser companycompany.. ThereforeTherefore itit isis importantimportant thatthatthethe installationinstallation precededpreceded byby throughthrough planningplanning andand designdesign..

TwoTwo issuesissues areare discusseddiscussed herehere::

11.. FMSFMS planningplanning andand designdesign issuesissues..


11.. FMSFMS planningplanning andand designdesign issuesissues..

22.. FMSFMS operationaloperational issuesissues..

FMS Planning and Design IssuesFMS Planning and Design Issues

FMS planning issues:FMS planning issues:

1.1. Part family Part family considerationsconsiderations

2.2. Processing Processing requirementsrequirements

3.3. Physical characteristics Physical characteristics of the work partsof the work parts

FMS design issuesFMS design issues

1.1. Types of workstationsTypes of workstations

2.2. Variation in process routing and Variation in process routing and FMS layoutFMS layout

3.3. Material handling systemMaterial handling system

4.4. WorkWork--inin--process and storage process and storage capacitycapacity


of the work partsof the work parts

4.4. Production volumeProduction volumecapacitycapacity

5.5. ToolingTooling

6.6. Pallet fixturesPallet fixtures

FMS Operational IssuesFMS Operational IssuesOnceOnce FMSFMS isis installedinstalled thenthen thethe existingexisting resourcesresources ofof thethe FMSFMSmustmust bebe optimizedoptimized toto meetmeet productionproduction requirementsrequirements andand achieveachieveoperationaloperational objectivesobjectives relatedrelated toto profit,profit, qualityquality andand customercustomersatisfactionsatisfaction..

11.. SchedulingScheduling andand dispatchingdispatching

22..MachineMachine loadingloading

PartPart routingrouting


33.. PartPart routingrouting

44.. PartPart groupinggrouping

55.. ToolTool managementmanagement

66.. PalletPallet andand fixturefixture allocationallocation

Thank you…


Thank you…

lecture 25 flexible manufacturing systems [compatibility mode]

Technology

types of fms fms

fms technology

fms machining system

characteristics of fms

history of fms

words fms

fme gik institute

storage system