Senior Design Lecture3

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Senior DesignSenior Design

Fall 2005, Week 3Fall 2005, Week 3

Notes are based on EngineeringNotes are based on EngineeringDesign and Design for ManufacturingDesign and Design for Manufacturing

A Structured Approach by John R. A Structured Approach by John R.

Dixon and Corrado PoliDixon and Corrado Poli



Lecture OverviewLecture Overview

GroupsGroups

ProjectsProjects Conceptual Design OverviewConceptual Design Overview

Formulating the problemFormulating the problem

Customer AttributesCustomer Attributes Engineering CharacteristicsEngineering Characteristics

Engineering Design SpecificationEngineering Design Specification



GroupsGroups

Group 1 (Energy 1Group 1 (Energy 1 project presented by Dr.project presented by Dr.Fl

etcher)Fletcher) Richelle AtienzaRichelle Atienza Holman ChuaHolman Chua Jason GarnerJason Garner Jason HarringtonJason Harrington Joshua SeveranceJoshua Severance

Group 2 (ASME 1)Group 2 (ASME 1) William BerryWilliam Berry Nicholas FonderNicholas Fonder Jason KardosJason Kardos James MartiniJames Martini

Group 3 (Energy 2Group 3 (Energy 2 project to be discussedproject to be discussed

wi

th Dr. Fletcher)with Dr. Fletcher) Sean MochockiSean Mochocki Evan McNayEvan McNay Lince PhilipLince Philip Richard ThompsonRichard Thompson Stephen ThompsonStephen Thompson

Group 4 (ASME 2)Group 4 (ASME 2) Justin CaudleJustin Caudle Luke DelaneyLuke Delaney Joshua IsaacsonJoshua Isaacson Peter VergenzPeter Vergenz

Group 5 (ExtruderGroup 5 (Extruder Project presented by Dr.Project presented by Dr. Ad

ewale or a modification to the project) Adewale or a modification to the project) Anthony Barletta Anthony Barletta Daniel JonesDaniel Jones Parineeta NayyarParineeta Nayyar Spencer SchwabSpencer Schwab



Engineering ConceptualEngineering Conceptual

DesignDesign The GoalThe Goal

Determine the physical concept of the designed object Determine the physical concept of the designed object Information about the physical principles by which the object Information about the physical principles by which the object

will achieve its principal functionswill achieve its principal functions An abstract physical description of the object called the An abstract physical description of the object called the

embodiment embodiment Embodiment: Abstract physical description with few detailsEmbodiment: Abstract physical description with few details

providedprovided

Beam is long and slender member of uniform cross sectionBeam is long and slender member of uniform cross sectionbut we dont know the exact cross sectional shape orbut we dont know the exact cross sectional shape ordimensionsdimensions

The process of decompositionThe process of decomposition

Guided IterationGuided Iteration



The process ofThe process of

decompositiondecomposition It is necessary to decompose the design intoIt is necessary to decompose the design into

more manageable submore manageable sub--assemblies/components.assemblies/components.

Helps in finding creative solutions and ultimatelyHelps in finding creative solutions and ultimatelygenerating a superior designgenerating a superior design

Two primary approaches of conceptualTwo primary approaches of conceptualdecomposition are useddecomposition are used Direct decompositionDirect decomposition

FunctionFunction--First decompositionFirst decomposition Will need to include the couplings betweenWill need to include the couplings between

subsystemssubsystems How are forces transferred? Energy transfer?How are forces transferred? Energy transfer?



Direct DecompositionDirect Decomposition

A product is composed of the subsidiary A product is composed of the subsidiarycomponents (the design is not reallycomponents (the design is not reallydecomposed)decomposed)

Ex: An automobile is decomposed into itsEx: An automobile is decomposed into itsengine, drive train, body, suspensionengine, drive train, body, suspensionsystem, steering system.system, steering system.

Then you work on each of the decomposedThen you work on each of the decomposed

systems and find the best design for each.systems and find the best design for each. This decomposition method minimizesThis decomposition method minimizes

creative new ideas.creative new ideas.



Direct DecompositionDirect Decomposition

continuedcontinued Often used by Mechanical EngineersOften used by Mechanical Engineers

A sketch is commonly used identifying the A sketch is commonly used identifying the

embodiment embodiment Ex: For a bicycle we would identify theEx: For a bicycle we would identify the

handle bar (but for what function)handle bar (but for what function)

Ex: Design a breaking system for anEx: Design a breaking system for an

automobileautomobile Foot pedal, hydraulic system, and brake shoesFoot pedal, hydraulic system, and brake shoes

and drums.and drums.



FunctionFunction--FirstFirst

DecompositionDecomposition First the functions are identifiedFirst the functions are identified

without any embodiments assumedwithout any embodiments assumed

Then embodiments are identified toThen embodiments are identified tofulfill the functional needsfulfill the functional needs

This process often helps identifyThis process often helps identify

creative solutionscreative solutions

Abstract way of thinking. Abstract way of thinking.



Overview of Guided IterationOverview of Guided Iteration Applied to Engineering Applied to Engineering

Conceptual DesignConceptual Design Formulating the Engineering Conceptual Deisgn Problem: The Engineering DesignFormulating the Engineering Conceptual Deisgn Problem: The Engineering Design

SpecificationSpecification The Engineering Design Specification is used during the conceptual design stage and through theThe Engineering Design Specification is used during the conceptual design stage and through the

rest of the design stages.rest of the design stages. Should be a written document Should be a written document Convert the vague, qualitative, and incomplete information that is generally available at theConvert the vague, qualitative, and incomplete information that is generally available at the

beginning of the conceptual design stage into a set of specific, quantitative, completebeginning of the conceptual design stage into a set of specific, quantitative, completeperformance requirementsperformance requirements

Will use Quality Function Deployment (more to come)Will use Quality Function Deployment (more to come) Ex: Should be easy to carryEx: Should be easy to carry the weight should be less than 20lbthe weight should be less than 20lb

Generating Alternatives in Engineering Conceptual Design ProblemsGenerating Alternatives in Engineering Conceptual Design Problems The selection of the best possible conceptual design is crucial in obtaining the best possible finalThe selection of the best possible conceptual design is crucial in obtaining the best possible final

design solution.design solution. Mistakes at the conceptual design stage are extremely costly if you must backtrack when in theMistakes at the conceptual design stage are extremely costly if you must backtrack when in the

configuration, parametric, and detailed design stages.configuration, parametric, and detailed design stages.

Evaluating Alternatives in Engineering Conceptual DesignEvaluating Alternatives in Engineering Conceptual Design Alternatives are rated and compared Alternatives are rated and compared

Guided RedesignGuided Redesign Illuminate the specific characteristics of proposed alternatives that are weak and strong.Illuminate the specific characteristics of proposed alternatives that are weak and strong. Is the design goodIs the design good--enough?enough?



Summary of guided iteration methodsSummary of guided iteration methods

(E

ngineering Conceptual Design)(E

ngineering Conceptual Design)Steps in GI processSteps in GI process MethodsMethods

Problem formulationProblem formulation Quality Function Deployment andQuality Function Deployment andHouse of QualityHouse of Quality

Engineering Design SpecificationEngineering Design Specification

Generation of AlternativesGeneration of Alternatives Search for alternatives physical lawsSearch for alternatives physical lawsand effectsand effects

Techniques for creativityTechniques for creativity

Memory SearchMemory Search

Analogous Problems Analogous Problems

Literature searchesLiterature searches

Evaluation of alternativesEvaluation of alternatives Pughs methodPughs method

Dominics MethodDominics Method

Pahl and Beitz MethodPahl and Beitz Method

Redesign, Guided by the evaluationRedesign, Guided by the evaluation

and physical reasoningand physical reasoning

Modify Existing AlternativesModify Existing Alternatives

New alternativesNew alternatives



Formulating the Problem: TheFormulating the Problem: The

Engineering Design SpecificationEngineering Design Specification Includes statementsIncludes statements

InIn--use purposes, anduse purposes, and

Functional requirementsFunctional requirements

Some information may be available from marketingSome information may be available from marketingand industrial design stageand industrial design stage

Most information available at this stage is typicallyMost information available at this stage is typicallyqualitative, incomplete, and/or approximatequalitative, incomplete, and/or approximate

The Engineering Design Specification will be used inThe Engineering Design Specification will be used infuture design stages so care should be put intofuture design stages so care should be put intomaking it as detailed and complete as possible.making it as detailed and complete as possible.



Overview: EngineeringOverview: Engineering

Design Specification (Specs)Design Specification (Specs) inin--use purposesuse purposes

Primary PurposePrimary Purpose Unintended PurposeUnintended Purpose Special PurposeSpecial Purpose

Functional RequirementsFunctional Requirements Product performancesProduct performances

Functional Performance RequirementsFunctional Performance Requirements Complementary PerformanceComplementary Performance

Environmental and other conditionsEnvironmental and other conditions Economic issuesEconomic issues Physical attributesPhysical attributes Process technologiesProcess technologies Aesthetics Aesthetics Product development time and cost Product development time and cost

Before developing the Specs it is best to understand the customer needs.Before developing the Specs it is best to understand the customer needs. House of QualityHouse of Quality



Quality FunctionQuality FunctionDeployment (QFD) and theDeployment (QFD) and theHouse of Quality (HoQ)House of Quality (HoQ) QFD: term used to describe a strategyQFD: term used to describe a strategy

for focusing engineering designfor focusing engineering design

attention on quality issues asattention on quality issues asperceived by customersperceived by customers

HoQ: A technique used for structuringHoQ: A technique used for structuring

information commonly used toinformation commonly used toimplement QFD.implement QFD.



House of QualityHouse of Quality

Matrix that relates the customers wants (Customer Attributes)Matrix that relates the customers wants (Customer Attributes)to the technical product characteristics (Engineeringto the technical product characteristics (EngineeringCharacteristics)Characteristics)

Customer Attributes (CA)Customer Attributes (CA) Generally qualitativeGenerally qualitative

Fast, smooth, easyFast, smooth, easy

The Customer Attributes are listed to the left of the rows (alsoThe Customer Attributes are listed to the left of the rows (alsogroupedgrouped functions, features)functions, features)

Engineering Characteristics (EC)Engineering Characteristics (EC)

QualitativeQualitative Weight in poundsWeight in pounds

The Engineering Characteristics are listed at the top of theThe Engineering Characteristics are listed at the top of thecolumns (grouped by categories)columns (grouped by categories)

HoQ is also used for competitive benchmarkingHoQ is also used for competitive benchmarking



House of QualityHouse of Quality



Coffee Maker ExampleCoffee Maker Example

Customer AttributesCustomer Attributes Good coffeeGood coffee Nice looking coffee makerNice looking coffee maker Easy to cleanEasy to clean

Engineering CharacteristicsEngineering Characteristics

Goodness of coffee (in measurable quantities)Goodness of coffee (in measurable quantities) Functional requirementsFunctional requirements

TemperatureTemperature Flow rate of waterFlow rate of water Time the water takes to flow through the groundsTime the water takes to flow through the grounds Temperature when poured into the cupTemperature when poured into the cup

EC will include requirements such as the electrical resistance to the heater, theEC will include requirements such as the electrical resistance to the heater, thesize of the tube supplying the hot water to the coffee grounds, and othersize of the tube supplying the hot water to the coffee grounds, and otherfactors having to do with geometry and materials.factors having to do with geometry and materials.

Since there are yet no proposed designs there are no engineeringSince there are yet no proposed designs there are no engineeringcharacteristics yet.characteristics yet.

Determine the Customer Attributes, then write the Specs and thenDetermine the Customer Attributes, then write the Specs and thenreturn to the Engineering Characteristicsreturn to the Engineering Characteristics



CD protective portableCD protective portable

carrying casecarrying case Customer AttributesCustomer Attributes

Protects the discsProtects the discs Attractive Attractive InexpensiveInexpensive

Can identify the contentsCan identify the contents Stays closedStays closed Easy to openEasy to open Cant be used as a coaster forCant be used as a coaster for

coffee cupscoffee cups Holds at least 6 CDsHolds at least 6 CDs Doesnt pop open on its ownDoesnt pop open on its own

Wont break if droppedWont break if dropped Compact Compact

Eliminate redundanciesEliminate redundancies Organize the list hierarchicallyOrganize the list hierarchically

Protects the discsProtects the discs Stays closedStays closed

Wont break if droppedWont break if dropped Cant be used as a coaster forCant be used as a coaster for

coffee cupscoffee cups

Convenient to useConvenient to use Easy to OpenEasy to Open Ca identify the contentsCa identify the contents Compact Compact

Attractive Attractive

Holds at least six CDsHolds at least six CDs InexpensiveInexpensive

Often priorities are assigned toOften priorities are assigned tothe customer attributes that the customer attributes that total 100 unitstotal 100 units



Assignment of priorities Assignment of priorities

Stays closedStays closed 2020

Wont break if droppedWont break if dropped 1414

Cant be used as a coaster for coffee cupsCant be used as a coaster for coffee cups 55

Easy to OpenEasy to Open 2020

Can identify the contentsCan identify the contents 1010

Compact Compact 77

Attractive Attractive 55

Holds at least six CDsHolds at least six CDs 77 InexpensiveInexpensive 1010

TotalTotal 100100



Content of the EngineeringContent of the Engineering

Design SpecificationDesign Specification Develop the Specs after the CustomerDevelop the Specs after the Customer Attributes have been identified Attributes have been identified

The Specs should includeThe Specs should include

InIn--use purposesuse purposes

Functional RequirementsFunctional Requirements




Primary Intended Use By CustomersPrimary Intended Use By Customers ExamplesExamples

To make coffeeTo make coffee To convert electrical to rotating energyTo convert electrical to rotating energy

To aid in the catching of a baseball and to protect the hand when doing soTo aid in the catching of a baseball and to protect the hand when doing so Some products have multiple usesSome products have multiple uses Baseball glove exampleBaseball glove example Hammer: Drive and pull nailsHammer: Drive and pull nails

Predictable Unintended UsesPredictable Unintended Uses Wrenches are used as hammersWrenches are used as hammers Screw drivers as chiselsScrew drivers as chisels Shelves and chairs as step laddersShelves and chairs as step ladders People standing (and jumping) on top of the washing machinePeople standing (and jumping) on top of the washing machine People driving with the windshield sun protector???? Remove whenPeople driving with the windshield sun protector???? Remove when

driving. UNF parking tag.driving. UNF parking tag. NOT enough to use warnings.NOT enough to use warnings. Must design with unintended uses inMust design with unintended uses in

mind. Legal and common sense reasons.mind. Legal and common sense reasons. Design the wrench such that it is reasonable safe to use as a hammerDesign the wrench such that it is reasonable safe to use as a hammer




Special Purpose FeaturesSpecial Purpose Features

Features that enhance the product Features that enhance the product

Rechargeable electric shaver that can beRechargeable electric shaver that can bedirectly plugged into the outlet rather thandirectly plugged into the outlet rather thanhaving an inconvenient cord.having an inconvenient cord.

Redial button on your telephoneRedial button on your telephone

NoNo--drip tops on laundry detergentsdrip tops on laundry detergents

May rate the special purpose features asMay rate the special purpose features asessential, important, or desirableessential, important, or desirable




Product performancesProduct performances Functional Performance RequirementsFunctional Performance Requirements

Capacity (energy or material flow rate, force, )Capacity (energy or material flow rate, force, ) Input and output conditions (temperature, energy, pressures, flows,Input and output conditions (temperature, energy, pressures, flows,

power, deflections, forces)power, deflections, forces) EfficiencyEfficiency Accuracy and sensitivity Accuracy and sensitivity

Complementary PerformanceComplementary Performance Useful lifeUseful life ReliabilityReliability RobustnessRobustness SafetySafety NoiseNoise Legal requirementsLegal requirements Maintenance requirementsMaintenance requirements Requirements on users (skills, speed, knowledge, )Requirements on users (skills, speed, knowledge, )




ContinuedContinued Environmental and other conditionsEnvironmental and other conditions

Temperature, humidity, corrosive elements, noise, dirt, vibration, electricTemperature, humidity, corrosive elements, noise, dirt, vibration, electricor magnetic field.or magnetic field.

Extremes of variationsExtremes of variations

How product will be disposed, how it will influence the environment,How product will be disposed, how it will influence the environment,design for disdesign for dis--assembly.assembly. Is pollution a problem?Is pollution a problem?

Economic issuesEconomic issues Tooling cost, initial product cost, maintenance costs, return onTooling cost, initial product cost, maintenance costs, return on

investment, cash flow, break even timeinvestment, cash flow, break even time

Physical attributesPhysical attributes

Weight, size, shape, surface finish, Weight, size, shape, surface finish, Aesthetics Aesthetics

Style, uniqueness, Style, uniqueness, Work with marketing teamWork with marketing team

Product development time and cost Product development time and cost Process technologiesProcess technologies

restrictions on manufacturing processesrestrictions on manufacturing processes



Expressing FunctionalExpressing Functional

RequirementsRequirements QualitativelyQualitatively

Verbal statement (high, low, moderate, fast, slow, ) Verbal statement (high, low, moderate, fast, slow, )

As extremum goals, with or without limits As extremum goals, with or without limits Mass should be as low as possibleMass should be as low as possible

Mass should be as low as possible but no higher than 10Mass should be as low as possible but no higher than 10lblb

As target values with tolerance As target values with tolerance The power output of an engine should be 5 Hp +/The power output of an engine should be 5 Hp +/-- 0.250.25

HpHp

As ranges As ranges Length must be between 3.7 and 4.8 inchesLength must be between 3.7 and 4.8 inches



Completeness andCompleteness andInvariability of theInvariability of the

Engineering DesignEngineering Design The Specs should never be though of The Specs should never be though of

as complete or invariable at any stageas complete or invariable at any stage

in the design process.in the design process.

Specifications should beSpecifications should be as completeas completeas possibleas possible onon what the designedwhat the designed

object is to doobject is to do. They should. They should say assay aslittle as possiblelittle as possible about about how thehow therequirements are to be met.requirements are to be met.



Example: A Portable WindExample: A Portable Wind

Chill MeterChill Meter InIn--purpose usepurpose use

Primary Intended UsePrimary Intended Use

For skiers and winter hikers: to be able to determineFor skiers and winter hikers: to be able to determinethe sothe so--called wind chill factor easily and convenientlycalled wind chill factor easily and conveniently

Unintended Uses:Unintended Uses:

Non anticipatedNon anticipated

Special FeaturesSpecial Features

Indicate temperature, wind velocity seperately as wellIndicate temperature, wind velocity seperately as wellas the combined wind chillas the combined wind chill



Example continuedExample continued

Functional requirementsFunctional requirements Performance requirementsPerformance requirements

Functional Performance requirementsFunctional Performance requirements Indicated reading should be accurate within one degreeIndicated reading should be accurate within one degreeusing U.S. Weather Bureau formula for the wind chillusing U.S. Weather Bureau formula for the wind chill

The meter should provide a reading after no more thanThe meter should provide a reading after no more than20 seconds for reaching equilibrium with the outdoor20 seconds for reaching equilibrium with the outdoorenvironment environment

The meter should perform with the above accuracy fromThe meter should perform with the above accuracy from32 F to 50 F, and from wind velocities from 10 mph to32 F to 50 F, and from wind velocities from 10 mph to60 mph. Accuracy should not be affected by mis60 mph. Accuracy should not be affected by mis--orientation with the wind direction up to 20 degreeorientation with the wind direction up to 20 degreeangleangle




Functional requirementsFunctional requirements Performance requirementsPerformance requirements

Complementary performance requirements:Complementary performance requirements:

The expected life in normal use should be at least 10The expected life in normal use should be at least 10yearsyears

The reliability should be such that no more than one inThe reliability should be such that no more than one in1000 sold will be returned for repairs or replacement 1000 sold will be returned for repairs or replacement during the 1during the 1st st year of use.year of use.

Must be able to withstand shocks and pressure without Must be able to withstand shocks and pressure without damage when carried in jacket pocketsdamage when carried in jacket pockets

Hiker or skier should not be cut by the device if (s)heHiker or skier should not be cut by the device if (s)hefalls.falls.

No maintenance should be required (except batteryNo maintenance should be required (except batteryreplacement replacement if used)if used)




Environmental conditionsEnvironmental conditions Use at previously mentioned conditionsUse at previously mentioned conditions Survive summer shipping storage up to 120 FSurvive summer shipping storage up to 120 F

and 80% humidityand 80% humidity Economic issuesEconomic issues

$10 (for a volume of 5000)$10 (for a volume of 5000)

Physical AttributesPhysical Attributes

To be carried in a ski or hiking jacket pocket To be carried in a ski or hiking jacket pocket No more than 16 ozNo more than 16 oz 3 x 5 x ¾ in3 x 5 x ¾ in33




Process TechnologiesProcess Technologies NoneNone

Aesthetics Aesthetics Should look like a rugged, reliable, accurate deviceShould look like a rugged, reliable, accurate device

compatible with the quality equipment needed by skierscompatible with the quality equipment needed by skiersand hikersand hikers

Product development time and cost Product development time and cost The product should be designed and prototyped byThe product should be designed and prototyped by

<specific date>. Design and development cost, including<specific date>. Design and development cost, includingengineering , model shop, and laboratory should not engineering , model shop, and laboratory should not exceed <specified amount>exceed <specified amount>



Assignment for next week Assignment for next week

Meet with your groupMeet with your group Define a project leaderDefine a project leader

Determine times when you will work on theDetermine times when you will work on theproject as a groups each weekproject as a groups each week At least 2 times (Beginning of the week discuss At least 2 times (Beginning of the week discuss

the tasks, split and work independently, regroup)the tasks, split and work independently, regroup)

Define the Customer Attributes withDefine the Customer Attributes withprioritiespriorities

Start discussing the SpecsStart discussing the Specs

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Senior Design Lecture3