Transcription
Design for ManufacturingTeaching materials to accompany:Product Design and DevelopmentChapter 11Karl T. Ulrich and Steven D. Eppinger2nd Edition, Irwin McGraw-Hill, 2000.
Product Design and DevelopmentKarl T. Ulrich and Steven D. Eppinger2nd edition, Irwin McGraw-Hill, 2000.Chapter Table of ionDevelopment Processes and OrganizationsProduct PlanningIdentifying Customer NeedsProduct SpecificationsConcept GenerationConcept SelectionConcept TestingProduct ArchitectureIndustrial DesignDesign for ManufacturingPrototypingProduct Development EconomicsManaging Projects
Product Development efinementProductionProductionRamp-UpRamp-UpHow can we emphasize manufacturing issuesthroughout the development process?
Design for Manufacturing Example:GM 3.8-liter V6 Engine
Understanding Manufacturing CostsManufacturing orProcessingToolingEquipmentand ToolingOverheadSupportIndirectAllocation
Definition Design for manufacturing (DFM) is a developmentpractice emphasizing manufacturing issuesthroughout the product development process. Successful DFM results in lower production costwithout sacrificing product quality.
Three Methods to Implement DFM1. Organization: Cross-Functional Teams2. Design Rules: Specialized by Firm3. CAD Tools: Boothroyd-Dewhurst Software
Design for Assembly RulesExample set of DFA guidelinesfrom a computer manufacturer.1.2.3.4.5.6.7.8.9.10.Minimize parts count.Encourage modular assembly.Stack assemblies.Eliminate adjustments.Eliminate cables.Use self-fastening parts.Use self-locating parts.Eliminate reorientation.Facilitate parts handling.Specify standard parts.
Design for Assembly Key ideas of DFA:–Minimize parts count–Maximize the ease of handling parts–Maximize the ease of inserting parts Benefits of DFA–Lower labor costs–Other indirect benefits Popular software developed byBoothroyd and Dewhurst.–http://www.dfma.com
To Compute Assembly TimeHandling Time Insertion TimeAssembly Time
Method for Part Integration Ask of each part in a candidate design:1. Does the part need to move relative to the rest ofthe device?2. Does it need to be of a different material becauseof fundamental physical properties?3. Does it need to be separated from the rest of thedevice to allow for assembly, access, or repair? If not, combine the part with another part in thedevice.
Videocassette DFM Exercise 2 billion worldwide annual volume 7 major producers of 1/2” cassette shells JVC licenses the VHS standard– dimensions, interfaces, light path, etc VHS cassette shells cost 0.25 each What is a 0.01 cost reduction worth?
DFM Strategy is onStrategyDFMStrategy
Concept GenerationTeaching materials to accompany:Product Design and DevelopmentChapter 6Karl T. Ulrich and Steven D. Eppinger2nd Edition, Irwin McGraw-Hill, 2000.
Product Design and DevelopmentKarl T. Ulrich and Steven D. Eppinger2nd edition, Irwin McGraw-Hill, 2000.Chapter Table of ionDevelopment Processes and OrganizationsProduct PlanningIdentifying Customer NeedsProduct SpecificationsConcept GenerationConcept SelectionConcept TestingProduct ArchitectureIndustrial DesignDesign for ManufacturingPrototypingProduct Development EconomicsManaging Projects
Concept Development ctProductConcept(s)TestProductConcept(s)Perform Economic AnalysisBenchmark Competitive ProductsBuild and Test Models and lopmentDevelopmentPlan
Concept Generation Example:Power Nailer
Concept Generation ProcessClarifytheProblem Clarify the Problem– Problem Decomposition External Search–––––Lead ernallySearchInternally Internal Search– Individual Methods– Group Methods Systematic Exploration– Classification Tree– Combination Table Reflect on the Process– Continuous ImprovementExploreSystematicallyReflect on theSolutions andthe Process
Concept Generation Exercise:Vegetable Peelers
Vegetable Peeler Exercise:Voice of the Customer "Carrots and potatoes are very different.""I cut myself with this one.""I just leave the skin on.""I'm left-handed. I use a knife.""This one is fast, but it takes a lot off.""How do you peel a squash?""Here's a rusty one.""This looked OK in the store."
Vegetable Peeler Exercise:Key Customer Needs1. The peeler peels a variety of produce.2. The peeler can be used ambidextrously.3. The peeler creates minimal waste.4. The peeler saves time.5. The peeler is durable.6. The peeler is easy to clean.7. The peeler is safe to use and store.8. The peeler is comfortable to use.9. The peeler stays sharp or can be easily sharpened.
Problem Decomposition:Function DiagramINPUTOUTPUTEnergy (?)Energy (?)Material (nails)Hand-heldnailerSignal (tool "trip")EnergyNails"Trip" oftoolMaterial (driven nail)Signal (?)Store oracceptexternalenergyConvertenergy pTriggertoolApplytranslationalenergy to nailDrivennail
External Search:Hints for Finding Related Solutions Lead Users– benefit from improvement– innovation source Benchmarking– competitive products Experts– technical experts– experienced customers Patents– search related inventions Literature– technical journals– trade literature
Capture Innovation from Lead Users:Utility Light Example
Capture Innovation from Lead Users:Utility Light Example
Internal Search:Hints for Generating Many Concepts Suspend judgmentGenerate a lot of ideasInfeasible ideas are welcomeUse graphical and physical mediaMake analogiesWish and wonderSolve the conflictUse related stimuliUse unrelated stimuliSet quantitative goalsUse the gallery methodTrade ideas in a group
Systematic Exploration:Concept Combination TableConvert ElectricalEnergy toTranslationalEnergyAccumulateEnergyrotary motor w/transmissionspringlinear motormoving masssolenoidrail gunApplyTranslationalEnergy to Nailsingle impactmultiple impactspush nail
Concept TestingTeaching materials to accompany:Product Design and DevelopmentChapter 8Karl T. Ulrich and Steven D. Eppinger2nd Edition, Irwin McGraw-Hill, 2000.
Product Design and DevelopmentKarl T. Ulrich and Steven D. Eppinger2nd edition, Irwin McGraw-Hill, 2000.Chapter Table of ionDevelopment Processes and OrganizationsProduct PlanningIdentifying Customer NeedsProduct SpecificationsConcept GenerationConcept SelectionConcept TestingProduct ArchitectureIndustrial DesignDesign for ManufacturingPrototypingProduct Development EconomicsManaging Projects
Product Development tionRamp-UpRamp-UpQuantitativeConceptTesting
Concept Development ctProductConcept(s)TestProductConcept(s)Perform Economic AnalysisBenchmark Competitive ProductsBuild and Test Models and lopmentDevelopmentPlan
Concept Testing is Used forSeveral Purposes Go/no-go decisionsWhat market to be in?Selecting among alternative conceptsConfirming concept selection decisionBenchmarkingSoliciting improvement ideasForecasting demandReady to launch?
Concept Testing Process Define the purpose of the testChoose a survey populationChoose a survey formatCommunicate the conceptMeasure customer responseInterpret the resultsReflect on the results and the process
Concept Testing Example:emPower Electric Scooter
Scooter Example Purpose of concept test:– What market to be in? Sample population:– College students who live 1-3 miles fromcampus– Factory transportation Survey format:– Face-to-face interviews
Communicating the Concept Verbal descriptionSketchPhotograph or renderingStoryboardVideoSimulationInteractive multimediaPhysical appearance modelWorking prototype
Verbal Description The product is a lightweight electric scooter that canbe easily folded and taken with you inside a buildingor on public transportation. The scooter weighs about 25 pounds. It travels atspeeds of up to 15 miles per hour and can go about12 miles on a single charge. The scooter can be recharged in about two hoursfrom a standard electric outlet. The scooter is easy to ride and has simple controls— just an accelerator button and a brake.
Sketch
Rendering
Storyboard
3D Solid CAD Model
Appearance Model
Working Prototype
Beta Prototype
VideoAnimationInteractive MultimediaLive Demonstration
Survey Format PART 1, Qualification– How far do you live from campus? If not 1-3 miles, thank the customer and end interview. – How do you currently get to campus from home?– How do you currently get around campus? PART 2, Product Description– Present the concept description.
Survey Format PART 3, Purchase Intent– If the product were priced according to yourexpectations, how likely would you be to purchasethe scooter within the next year?I woulddefinitely notpurchasethe scooter.I wouldprobably notpurchasethe scooter.I mightor might notpurchasethe scooter.I wouldprobablypurchasethe scooter.I woulddefinitelypurchasethe scooter.“second box”“top box”
Survey Format PART 4, Comments– What would you expect the price of the scooter tobe?– What concerns do you have about the productconcept?– Can you make any suggestions for improving theproduct concept? Thank you.
Interpreting the Results:Forecasting SalesQ NxAxP QNAP sales (annual) number of (annual) purchases awareness x availability (fractions) probability of purchase (surveyed) Cdef x Fdef Cprob x Fprob“top box”“second box”
Forecasting Example:College Student Market N off-campus grad students (200,000)A 0.2 (realistic) to 0.8 (every bike shop)P 0.4 x top-box 0.2 x second-boxQ Price point 795
Forecasting Example:Factory Transport Market N current bicycle and scooter sales tofactories (150,000) A 0.25 (single distributor’s share) P 0.4 x top-box 0.2 x second-box Q 150,000 x 0.25 x [0.4 x 0.3 0.2 x 0.2] 6000 units/yr Price point 1500
emPower’s Market Decision: Factory Transportation
Production Product
Sources of Forecast Error Word-of-Mouth EffectsQuality of Concept DescriptionPricingLevel of PromotionCompetition
Discussion Why do respondents typically overestimatepurchase intent?– Might they ever underestimate intent? How to use price in surveys? How much does the way the concept iscommunicated matter?– When shouldn’t a prototype model be shown? How do you increase sales, Q? How does early (qualitative) concept testingdiffer from later (quantitative) testing?
Managing Complex SystemDevelopment ProjectsProf. Steven D. EppingerMassachusetts Institute of TechnologySloan School of ManagementEngineering Systems DivisionLeaders for Manufacturing ProgramSystem Design and Management Program 2002 Steven D. Eppingerhttp://web.mit.edu/dsm
Session Outline Motivation: Managing Project Structure– Concurrent Engineering in the Large Design Structure Matrix––––Information Flow ModelingTask-Based DSMsSequencing AnalysisExample: Semiconductor Development Managing Design Iterations– Solving Coupled Issues Faster– Example: Instrument Cluster Systems Integration– Organization-Based DSM– System Architecture-Based DSM– Example: Engine Development DSM Web Site
Industrial Examplesand Research Sponsorsi ntelF I A T
Concurrent Engineeringin the Small Projects are executed by a cross-disciplinaryteam (5 to 20 people). Teams feature high-bandwidth technicalcommunication. Tradeoffs are resolved by mutualunderstanding. “Design and production” issues areconsidered simultaneously.
Concurrent Engineeringin the Large Large projects are organized as a network ofteams (100 to 1000 people). Large projects are decomposed into manysmaller projects. Large projects may involve developmentactivities dispersed over multiple sites. The essential challenge is to integrate theseparate pieces into a system solution. The needs for integration depend upon thetechnical interactions among the subproblems.
Sequencing Tasks in ProjectsThree Possible Sequences for Two led)BDependent(Series)
IDEF Diagrams We can represent theimportant task relationships.It is difficult to understandlarge, complex diagrams.
The Design Structure Matrix:An Information Exchange ModelA B C D E F G H I J K LABCDEFGHIJKL Interpretation: Task D requires information from tasks E, F, and L. Task B transfers information to tasks C, F, G, J, and K.Note: Information flows are easier to capture than work flows. Inputs are easier to capture than outputs. Donald V. Steward, Aug. 1981IEEE Trans. on Eng'g Mgmt.
The Design Structure Matrix(Partitioned, or Sequenced)B C A K L J F I E D H GTaskSequenceBCAKLJFIEDHG Sequential Parallel Coupled Note:Coupled tasks can be identified uniquely.The display of the matrix can be manipulated toemphasize certain features of the process flow.
insideSemiconductor Development 1525354555657585960Set customer targetEstimate sales volumesEstablish pricing directionSchedule project timelineDevelopment methodsMacro targets/constraintsFinancial analysisDevelop program mapCreate initial QFD matrixSet technical requirementsWrite customer specificationHigh-level modelingWrite target specificationDevelop test planDevelop validation planBuild base prototypeFunctional modelingDevelop product modulesLay out integrationIntegration modelingRandom testingDevelop test parametersFinalize schematicsValidation simulationReliability modelingComplete product layoutContinuity verificationDesign rule checkDesign packageGenerate masksVerify masks in fabRun wafersSort wafersCreate test programsDebug productsPackage productsFunctionality testingSend samples to customersFeedback from customersVerify sample functionalityApprove packaged productsEnvironmental validationComplete product validationDevelop tech. publicationsDevelop service coursesDetermine marketing nameLicensing strategyCreate demonstrationConfirm quality goalsLife testingInfant mortality testingMfg. process stabilizationDevelop field support planThermal testingConfirm process standardsConfirm package standardsFinal certificationVolume productionPrepare distribution networkDeliver product to customers234 x xxx xxx xx xxxxxxxxxxxxxx56789 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 Concurrent Activity Blocksxx x x x x x xx x x xx x x xx x xx x x O O Ox xx x x x xxx x x x x x xxx x x xxxx xxx xx x xx xxx x xxx x x x x xx x xx x x x x xxx xxx x xxxxxxxx x xxxxxxxx xxx xxxxGenerational LearningPotential IterationsOxOxxxxxxx xx x xx x x x xx x x x xx x x x x xx x x x xx x x x xx xx x xx xx xx x xxxxxxSequential ActivitiesxxxxxxxxxxxxOOOOOO xx x x xxxOOOOOxxO OOOOx x Ox xx x x xx xxxOOxxxOO O OO xxx x x xx x xO O OOxxxxxxxxxxxxx x x xx x xx xx x xxxxxx Planned IterationsO Unplanned IterationsO O xxxxx Information FlowsOOxxxO O O O xxxO Generational Learningxxxxxxxxxxxxxxxxxx xxxxxx x xx xx x x x xx x intel
How to Create a Task-BasedDesign Structure Matrix Model1. Select a process or sub-process to model.2. Identify the tasks of the process, who is responsiblefor each one, and the outputs created by each task.3. Lay out the square matrix with the tasks in the orderthey are nominally executed.4. Ask the process experts what inputs are used foreach task.5. Insert marks representing the information inputs toeach task.6. Optional: Analyze the DSM model by re-sequencingthe tasks to suggest a new process.7. Draw solid boxes around the coupled tasksrepresenting the planned iterations.8. Draw dashed boxes around groups of parallel(uncoupled) tasks.9. Highlight the unplanned iterations.
Design Iteration Product development is fundamentally iterative— yet iterations are hidden. Iteration is the repetition of tasks due to theavailability of new information.– changes in input information (upstream)– update of shared assumptions (concurrent)– discovery of errors (downstream) Engineering activities are repeated to improveproduct quality and/or to reduce cost. To understand and accelerate iterationsrequires– visibility of iterative information flows– understanding of the inherent process coupling
Instrument Cluster DevelopmentDelcoSupplier Casing DesignWiring LayoutLighting DetailsToolingHard PrototypeTesting XXXX XXXX X X X Casing DesignLighting DetailsWiring LayoutSoft PrototypeTestingRevisionHard Tooling Slower Design Process XXXX X X X X X X X XX X Faster Design ProcessSeveral planned iterationsFewer planned iterationsUsually one unplanned iterationPlanned revision cycleNo unplanned iterations
Lessons Learned: Iteration Development is inherently iterative. An understanding of the coupling is essential. Not everything should be concurrent inconcurrent engineering. Iteration results in improved quality. Iteration can be accelerated through:– information technology (faster iterations)– coordination techniques (faster iterations)– decreased coupling (fewer iterations) There are two fundamental types of iteration:– planned iterations (getting it right the first time)– unplanned iterations (fixing it when it’s not right)
Decomposition, Architecture,and IntegrationDecomposition is the process ofsplitting a complex system intosub-systems and/or components.System architecture is the resultingset of interactions among thecomponents.Integration is the process ofcombining these sub-systems toachieve an overall solution.System integration needs are determined bythe chosen decomposition and its resultingarchitecture.We map the structure of interactions in orderto plan for integration.
Organization DSM Application:Engine Development Site: General Motors Powertrain Division Product: “new-generation” engine Structure: 22 PDTs involved simultaneously
Decomposition of the EngineDevelopment Project22 PDTsDesignEngineEngine BlockCylinder HeadsCamshaft/Valve TrainPistonsConnecting RodsCrankshaftFlywheelAccessory DriveLubricationWater Pump/CoolingIntake ManifoldExhaustE.G.R.Air CleanerA.I.R.Fuel SystemThrottle BodyEVAPIgnition SystemElectronic Control ModuleElectrical SystemEngine AssemblyPDT composition1 product release engineer1 CAD designer3 manufacturing engineers2 purchasing representatives2 casting engineersmachine tool supplier1 production control analyst1 financial plannerproduction personnel
PDT InteractionsA B C D E F G H I Engine Block A ACylinder HeadsCamshaft/Valve TrainPistonsConnecting RodsCrankshaftFlywheelAccessory DriveLubricationWater Pump/CoolingIntake ManifoldExhaustE.G.R.Air CleanerA.I.R.Fuel SystemThrottle BodyEVAPIgnitionE.C.M.Electrical SystemEngine AssemblyBCD E FGHIJKLM QTUV I Frequency of PDT InteractionsDaily Weekly Monthly L M N O P Q R S T U V J K RS P NO B C D E F GH J K L M N O P Q R S T U V
System Team AssignmentsShort BlockEngine BlockCrankshaftFlywheelPistonsConnecting RodsLubricationInductionIntake ManifoldAccessory DriveFuel SystemAir CleanerThrottle BodyA.I.R.Valve TrainCylinder HeadsCamshaft/Valve TrainWater .P.Electrical SystemElectronic ControlIgnition
Existing System TeamsEngine BlockCrankshaftFlywheelPistonsConnecting RodsLubricationCylinder HeadsCamshaft/Valve TrainWater Pump/CoolingIntake ManifoldFuel SystemAccessory DriveAir CleanerA.I.R.Throttle BodyExhaustE.G.R.EVAPIgnitionE.C.M.Electrical SystemEngine AssemblyA F G D E A AFGD E IBCJ F G D E NO B C J K Frequency of PDT InteractionsDaily Weekly MonthlyP H N O Q L M R S T U VR MV U LT I QS K PHB C J K P H N O Q L M R S T U V I
Proposed System TeamsCrankshaftFlywheelConnecting RodsPistonsLubricationEngine BlockCamshaft/Valve TrainCylinder HeadsIntake ManifoldWater Pump/CoolingFuel SystemAir CleanerThrottle BodyEVAPCylinder HeadsIntake ManifoldA.I.R.ExhaustE.G.R.Accessory DriveIgnitionE.C.M.Electrical SystemEngine AssemblyFGEDIACB1F G E D IF A C B K J P N Q R B K O L M H S T U V G E D I K1 J P Team 1 C B1 K1 JA RL MH S T U V P N Team 3 B2OTeam 2 Q NIntegrationTeam K2 Q Team 4 K2 O L M H S T B2 R Frequency of PDT InteractionsDaily Weekly Monthly U V
Team 4ExhaustE.G.R.Team 1Team 2PistonsFlywheelConnecting Rods Engine Block Camshaft/Lubrication Valve TrainCrankshaftTeam 3A.I.R.Water Pump/CoolingCylinder HeadsIntake ManifoldE.V.A.P.Fuel SystemAir CleanerThrottle BodyAccessory DriveElectrical SystemIgnitionEngine AssemblyElectronic Control ModuleIntegration TeamPDT-to-System-Team Assignments
Lessons Learned: Integration Large development efforts require multipleactivities to be performed in parallel. The many subsystems must be integrated toachieve an overall system solution. Mapping the information dependence revealsan underlying structure for systemengineering. Organizations can be “designed” based uponthis structure.
System Architecture Example:P&W 4098 Jet Engine 9 Systems 54 Components 569 InterfacesDesign Interfaces: Spatial, Structural Energy, Materials Data, ControlsHPCLPC HPTFANB/DLPTMechanical ComponentsExternals and Controls (2)Modular SystemsDistributed Systems
Lessons Learned:Product/System Architecture Hierarchical system decompositions areevident. System architecting principles are at work. There is a disparity between known interfacesand unknown interactions. Integrating elements may be functional and/orphysical. Hypothesis: Density of known gsparsematuredenseclustered
Types of DSM Models and AnalysisData TypeAnalysis anizationClusteringComponent
MITDesign Structure MatrixWeb Sitehttp://web.mit.edu/dsm Tutorial Publications Examples Software Contacts Events
Managing ProjectsTeaching materials to accompany:Product Design and DevelopmentChapter 14Karl T. Ulrich and Steven D. Eppinger2nd Edition, Irwin McGraw-Hill, 2000.
Product Development efinementProductionProductionRamp-UpRamp-UpProject management is necessary throughout the development process.
Product Design and DevelopmentKarl T. Ulrich and Steven D. Eppinger2nd edition, Irwin McGraw-Hill, 2000.Chapter Table of ionDevelopment Processes and OrganizationsProduct PlanningIdentifying Customer NeedsProduct SpecificationsConcept GenerationConcept SelectionConcept TestingProduct ArchitectureIndustrial DesignDesign for ManufacturingPrototypingProduct Development EconomicsManaging Projects
Two Phases of Project ManagementProject ManagementProject PlanningProject Control
The Design Structure Matrix:An Information Exchange ModelA B C D E F G H I J K LABCDEFGHIJKL Interpretation: Task D requires information from tasks E, F, and L. Task B transfers information to tasks C, F, G, J, and K.Note: Information flows are easier to capture than work flows. Inputs are easier to capture than outputs.Donald V. Steward, Aug. 1981IEEE Trans. on Eng'g Mgmt.
The Design Structure Matrix(Partitioned, or Sequenced)B C A K L J F I E D H GTaskSequenceBCAKLJFIEDHG Sequential Parallel Coupled Note:Coupled tasks can be identified uniquely.The display of the matrix can be manipulated toemphasize certain features of the process flow.
FIAT Auto – Digital Layout ProcessResponsibleActivityaTop ManagementApprove product architecture/configurationaLayout Team LeaderDefine extended layout teambSystemsDetermine project quality objectivescLayout Team LeaderEstablish the need for prototypesdSystemsEstablish prototype specificationsbcdEstablish DMU, PMU and prototypes to be developedfPrepare activity/resource plangSystemsApprove layout team leader's activity/resource planhPlanningSystemsVerify the feasibility of the LO team's plan with other plansApprove no. of DMU, PMU and prototypes to be developedijLayout Team LeaderPlatform DirectorVerify that planning phase is completeAuthorize go ahead to next phaseklConcurrent EngineeringProvide CAD models in PDMmStyling CenterProvide style modelsnCore Layout TeamConcurrent EngineeringExtract CAD models from PDMConvert non-standard CAD modelsopCore Layout TeamConstruct DMUs from CAD modelsqCore Layout TeamVerify DMU completenessrLayout Team LeaderCore Layout TeamReview issues document from past projectDefine volumes for new componentsstCore Layout TeamLayout Team LeaderConstruct DMU for the verification processRequest missing CAD modelsuvConcurrent EngineeringProvide missing CAD models in PDMwCore Layout TeamVerify DMU using checklist # 80195xCore Layout TeamVerify style compatibilityyCore Layout TeamPrepare alternate solutionszCore Layout TeamAnalyze issues with appropriate members of the layout team aaExtended Layout TeamVerify overall DMU with all stakeholdersbbCore Layout TeamUpdate issues documentccConcurrent EngineeringModify CAD modelsddStyling CenterCore Layout TeamModify stylingModify component positioning in DMUeeffTop ManagementCore Layout TeamSelect two models of styleFreeze DMU (STEP1)gghhLayout TL/Production TechDefine information required for assembly processiiCore Layout TeamConcurrent EngineeringSpecify component connectivity constraintsPerform detail design for component connectivityjjkkProduction TechnologyVerify assembly feasibilitySafety CenterVerify safety objectivesmmVehicle MaintenanceLayout Team LeaderVerify vehicle maintenance feasibilityEstablish/communicate modifications to be donennooTop ManagementCore Layout TeamSelect one model of styleFreeze DMU (STEP 2)ppqqCore Layout TeamVerify that all critical CAD models are presentrrCore Layout TeamTestingPrepare reference list of CAD drawings for prototypingBuild prototypes for design validation (DV1)ssttRoad TestingRun experiments on prototypesuuCore Layout TeamPlatform DirectorVerify project quality objectivesAuthorize go ahead to next phasevvwwCore Layout TeamFreeze DMU (STEP 3)xxfghijklm nopqrstuvwxyz aa bb cc dd ee ff gg hh iijjkk ll mm nn oo pp qq rr ss tt uu vv ww xxabbProject PlanningccdeLayout Team LeaderLayout Team LeadereadeeffgghhiIjCAD Data CollectionjkkllmmDMU PreparationnnooppDMU lm nopqrstuvwxyz aa bb cc dd ee ff gg hh iigghhjjxxkk ll mm nn oo pp qq rr ss tt uu vv ww xxvvwwxx
PERT and CPM Charts4Start236 8Simple networkdiagrams are easy tounderstand.We cannot representthe coupled/iterativetask relationships.4Finish5days activity and durationactivity precedencecritical path
Critical Chain MethodStart 3315633Feeder2 Buffer439FinishProjectBufferProbability of Task Duration TimeStart with a sequential/parallel network.Use 50/50 task duration estimates. daysACompute the critical path, noting resources.Insert feeder and project buffers as safety.Ideal buffers are 50% of path duration.Monitor buffer status.Reduce buffers when tasks overrun.Ref: E.M. Goldratt, Critical Chain, North River Press, 1997.BC
Project Management Example:Kodak Cheetah Microfilm Cartridge
Three Fundamental Activity Relationships(a) SequentialReceive andAcceptSpecification(b) ParallelConceptGeneration/SelectionDesign BetaCartridgesProduce BetaCartridgesDesign BetaCartridgesTest BetaCartridgesDevelopTestingProgram(c) CoupledTest : Kodak Cheetah Microfilm Cartridge
PERT Chart and Critical PathABCDEFGA2Receive and Accept SpecificationConcept Generation/SelectionDesign Beta CartridgesProduce Beta CartridgesDevelop Testing ProgramTest Beta CartridgesDesign Production CartridgeB4C8HIJKLMND 85L 4GFEDesign MoldDesign Assembly ToolingPurchase Assembly EquipmentFabricate MoldsDebug MoldsCertify CartridgeInitial Production Run2HK 10I14Jtask
Design for Assembly Rules. Example set of DFA guidelines from a computer manufacturer. 1. Minimize parts count. 2. Encourage modular assembly. 3. Stack assemblies. . Product Design and Development. Karl T. Ulrich and Steven D. Eppinger 2nd edition, Irwin McGraw-Hill, 2000. Chapter Table of Contents. 1. Introduction
