ME2110 Lecture 6 : Conceptual Designsinghose.marc.gatech.edu/courses/me2110 Summer10...Concept 1: Gravity+Ramp+Friction Brake Concept 2: Mousetrap+Rip Cord+String Brake Concept 3:

ME2110

Lecture 6 :

Conceptual Design

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Key Concepts

• Structured Concept Generation processes• Functional Decomposition• Solution Principle Matrices• Morphological Charts• Objective Concept Evaluation

Outline

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1. Review Design Tools CoveredPUF and HoQ

2. Concept GenerationWhat is structured concept generation?

3. Design Tool 5 – Functional Decomposition4. Design Tool 6 – Solution Principle Matrix5. Design Tool 7 – Morphological Chart

6. Concept EvaluationWhat is structured concept generation?

7. Design Tool 8 – Evaluation Matrices

1. Design Tools to-date

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A. Customer/Product RequirementsProblem understanding, Initial Analysis

B. Design SpecificationTarget Performance Metrics, Design Constraints

C. Conceptual DesignI. Concept Generation

II. Concept Evaluation

D. Detail DesignE. PrototypingF. Design Finalization

I. Specification for Production

DT1 – P.U.F DT2 – H.o.Q

DT4 – Design Spec. Sheet

DT3 – Function tree

DT5 – Functional Decomposition

DT6 – S.P.M DT7 – Morph. Chart

DT5 – Evaluation Matrices

2. Concept Generation

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• Systematic identification of design alternatives• Many alternatives• Synthesis of concepts from function-level design

solutions (How’s)

What is Concept Generation

Design Tools• DT5 – Functional Decomposition• DT6 – Solution Principles Matrix• DT7 – Morphological Chart• DT8 – Evaluation Matrices

7

3. DT5 – Function Decomposition

1 2 3 54 6

7

1 2 3+4 5 6

7

Feed in1

Prepare2

Dispense3

Shape4

Separate5

Feed Out6

Return7

Dough ShapedDough

Waste Waste WasteAdditives

1 2 3+4+5 6

7

1 2+3 4+5 6

7

Shape DoughShaped Dough

ElossDoughAdditives

I

E

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4. DT6 - Solution Principle Matrix

Sub-func.

Solution Principles(Idea/Source)

1Idea:(Mechanical)RubonMaterial

(Mechanical)Squirt Material

(Mechanical)PlaceMaterial(likeLetterset)

(Chemical)Changepaper composition

Source:Standardproduct Team#2 Letterset Acidetching

1

1

(Chemical)Changepaper color(likeLitmuspaper)

(Electrical)Burnpaper (spark)

(likeoldfashionedstripchart recorders)

(Electrical)ElectrifyPaper (glow

discharge)

(Electrical)Staticchargetoholdmark

on(likeEtch-A-Sketch)

Fisher Scientific Team#3 Team#1 Etch-A-Sketch

1

(Thermal)Burnpaper (flame)

(Thermal)Heat paper (glowdischarge)

(Thermal)Melt onMark

(Magnetic)Attachmagneticmaterial(likerefrigerator magnets)

Team#2 Team#2 Waxseals Gift Store

2

(Biological)Growbacteria, fungus

(Biological)Modify(digest?)paper

(Optical)Changelight propertiesof

paper (reflectance, polarity)

(Optical)Changelight (hologram)

Team#2 BioTechMagazine Team#2 Team#2

2

(Mechanical)Ruboff Material

(Mechanical)Takeoff material

(Mechanical)Cover mark

(likewhiteout)

(Chemical)Changepaper composition

Standardproduct Team#2 Team#1 Team#2(Chemical)

Changepaper color(likedyingfabricthesame

color asastain)

(Chemical)Changemark(e.g., bleach)

(Electrical)Burnoff mark (spark)

ETC.

Team#1 Team#2 Team#2

Example: Design of a “Pencil” Sub-function 1: Make an Erasable MarkSub-function 2: Erase an Erasable Mark

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ME 2110: Creative Decisions and D i

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4. Combining Solution Principles

Sub-Functions

\Solutions 1 2 j m

1 F1 S11 S12 S1j S1m

2 F2 S21 S22 S2j S2m

i Fi Si2 Sij Sim

n Fn Sn1 Sn2 Snj Snm

Combination of Principles1 2

Combination 1: S11 + S21 + … + Sn1Combination 1: S11 + S22 + … + Sn2

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4. DT6 Example : A Simple Competition

20 ft

Star

t Lin

e

6.25 ft

12.5 ft

Objective: Place mass from Start line and place on target

11

Place Masson Target

MoveMass

Navigateto

Target

Brake onTarget

GeneratePower

TransmitPower

HitTarget


Start with a Function Tree

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Different working principles to satisfy the function “store energy” by varying the type of energy.

1

2

3

4

5

6

Mechanical Hydraulic Electrical Thermal

FlowingLiquid

HeatedLiquid

SuperheatedSteam

Type of EnergyWorking Principle

Battery

Inductance, L

Pot. Energy

mh

Hydraulicreservoire.g, Piston

Moving Massm

v

MassM, s, T

Flywheelω

J

+V-

J

vω WheeloninclinePlane

Liquid Res. Pot. E.

h

F

Spring Other SpringsComp. GasF


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5. DT-6 The Morphological Chart

Going from concept to physical reality

.........

Store/Acquire Power

Transmit Power

Brake on Target

Move Mass

Navigate to Target

Gravity Mouse Traps

Car Hit by Trap Rip Cord Effect Ramp Catapult

Rolling Friction String Break Anchor Rubber Stopper

Equal Size Wheels Larger Front Wheels

Rolling Sliding Projectile Launch...

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Concept 1: Gravity+Ramp+Friction BrakeConcept 2: Mousetrap+Rip Cord+String BrakeConcept 3: Gravity+Mousetrap+Friction Brake

Store/Acquire Power

Transmit Power

Brake on Target

Move Mass

Navigate to Target

Gravity Mouse Traps

Car Hit by Trap Rip Cord Effect Ramp Catapult

Rolling Friction String Break Anchor Rubber Stopper

Equal Size Wheels Larger Front Wheels

Rolling Sliding Projectile Launch...

5. DT-6 Morph Chart Example

Outline

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1. Review Design Tools CoveredPUF and HoQ

2. Concept GenerationWhat is structured concept generation?

3. Design Tool 5 – Functional Decomposition4. Design Tool 6 – Solution Principle Matrix5. Design Tool 7 – Morphological Chart

6. Concept EvaluationWhat is structured concept generation?

7. Design Tool 8 – Evaluation Matrices

ME 2110: Creative Decisions and Design

THE BIG EGG-HUNT

6. Concept Evaluation Intro Example

ME 2110: Creative Decisions and Design 17

The Egg Basket Central Nest



A) Each rotten egg in your zone is -3 pointsB) Each regular egg (from the middle level of

the nest)in your zone is 1 pt.C) Each Big Egg (from the top level of the

nest) in your zone is 3 pts.D) All eggs in your basket are valued at 3X

the above values.


ME 2110: Creative Decisions and Design

Concept 1 2 3 4 5

CriteriaA DB AC TD UE MFΣ+Σ-ΣS

+ = better than datum; - = worse than datum; S = same as datum

6. DT8 – Evaluation Matrices

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+ = better than datum; - = worse than datum; S = same as datum

Concept

Criteria

Cost

GatheringAbility

Safety

RobustnessEase ofAssemblyΣ+Σ-Σs

1 2 3 4 5Bunny

D

A

T

U

M

Snake

+

S

S

S_

113

_

_

+

+

+

320

_

_

+

+

+

320

VoodooSpell

__

_

+

+

230

6. DT8 – 1st Level Evaluation Matrices

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Pts. Meaning

0 unsatisfactory

1 just tolerable

2 adequate

3 good

4 very good (ideal)

Pts. Meaning0 absolutely useless

solution1 very inadequate

solution2 weak solution3 tolerable solution4 adequate solution5 satisfactory solution6 good solution with few

drawbacks7 good solution8 very good solution9 solution exceeding

the requirement10 ideal solution

6. DT8 – Evaluation Scales

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6. DT8 – 2nd Level Evaluation Matrices

ME 2110: Creative Decisions and D i

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WEIGHT(0-4)

C1(RUB ON

- RUBOFF)

C2(PLACE

ON -TAKEOFF)

C3(PLACE

ON - RUBOFF)

WORKING PRINCIPLE:MAKES ERASABLEMARK

4 4 4

REMOVESERASABLE MARK

4 3 3

EMBODIMENT:HOLDS POINT 3 2 4

PRODUCTION:FEW PARTS 4 3 2SIMPLE TO MAKE 4 2 2

ASSEMBLY:EASY 3 3

OPERATION:COMFORTABLE TOUSE

2 2 3

LOW USE FORCE 3 3 4

MAINTENANCE:SHARPENABLE 4 4 4

SAFETY:DOESN’T HARMUSER BYBREAKING INTOSMALL, HARMFULPARTS

4 3 4

NOT POISONOUS 0 4 3

TOTAL POINTS:

6. DT8 – 3rd Level Evaluation Matrices


1. Formulate Many Alternate Concepts

2. Evaluate Concepts

3. Select Concepts for Further Refinement

Conceptual Design Summary

DT5 – Functional Decomposition

DT6 – S.P.M DT7 – Morph. Chart

DT5 – Evaluation Matrices

ME2110 Lecture 6 : Conceptual Designsinghose.marc.gatech.edu/courses/me2110 Summer10...Concept 1: Gravity+Ramp+Friction Brake Concept 2: Mousetrap+Rip Cord+String Brake Concept 3:

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