ME2110

Conceptual Design

© GIT2

Key Concepts

• Structured Concept Generation processes

• Functional Decomposition

• Solution Principle Matrices

• Morphological Charts

• Objective Concept Evaluation

2. Phases of Design

© GIT3

A. Customer/Product Requirements

B. Design Specification

C. Conceptual Design

I. Concept Generation

II. Concept Evaluation

D. Detail Design

E. Prototyping

F. Design Finalization

I. Specification for Production

Manufacturing

Usable Life

End of Life

PR

OD

UC

T L

IFE

CY

CL

E

Start

End

Concurrent

NOT

Linear

4. DT2 – House of Quality

© GIT4

Primary design tool in QFD

Ensures comprehensive

understanding of design task

and product requirements

Builds on P.U.F by adding

“rooms” for:

Design Trade-off & Analysis

Identification

Design Target Specification

Customer Competitive

Assessment

Technical Competitive

Assessment

Identifies key design

requirements for product

non-subjectively

5. HoQ – Detailed Example

© GIT5

Product: Car door

Customer requirements?

5. HoQ – Detailed Example

© GIT6

Product: Car door

Competitive Assessment & Customer Rating

© GIT7

© GIT8

Key Concepts

• Structured Concept Generation processes

• Functional Decomposition

• Solution Principle Matrices

• Morphological Charts

• Objective Concept Evaluation

9

3.Function Decomposition

1 2 3 54 6

7

1 2 3+4 5 6

7

Feed in

1

Prepare

2

Dispense

3

Shape

4

Separate

5

Feed Out

6

Return

7

Dough Shaped

Dough

Waste Waste WasteAdditives

1 2 3+4+5 6

7

1 2+3 4+5 6

7

Shape DoughShaped Dough

ElossDough

AdditivesI

E

© GIT

10

4. Solution Principle Matrix

Sub-func.

Solution Principles(Idea/Source)

1

Idea:(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

(likedyingfabricthesamecolor 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 Mark

Sub-function 2: Erase an Erasable Mark

© GIT

ME 2110: Creative Decisions and

Design

11

4. Combining Solution Principles

Sub-

Functions

\Solutions1 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 + … + Sn1

Combination 1: S11 + S22 + … + Sn2

© GIT

12

4. Example : A Simple Competition

20 ft

Sta

rt L

ine

6.25 ft

12.5 ft

Objective:

Place mass from Start line and place on target

13

Place Mass

on Target

Move

Mass

Navigate

to

Target

Brake on

Target

Generate

Power

Transmit

Power

Hit

Target

4. DT6 Example : A Simple Competition

Start with a Function Tree

14

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

...

15

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

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

6. Concept Evaluation Intro Example

ME 2110: Creative Decisions and

Design 18

A) Each rotten egg in your zone is -3 points

B) 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.

6. Concept Evaluation Intro Example

ME 2110: Creative Decisions and

Design

Concept 1 2 3 4 5

Criteria

A D

B A

C T

D U

E M

F

+

-

S

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

6. DT8 – Evaluation Matrices

20

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

Concept

Criteria

Cost

GatheringAbility

Safety

Robustness

Ease ofAssembly

+-

s

1 2 3 4 5

Bunny

D

A

T

U

M

Snake

+

S

S

S

_

1

1

3

_

_

+

+

+

3

2

0

_

_

+

+

+

3

2

0

VoodooSpell

_

_

_

+

+

2

3

0

6. DT8 – 1st Level Evaluation Matrices

21

Pts. Meaning

0 unsatisfactory

1 just tolerable

2 adequate

3 good

4 very good (ideal)

Pts. Meaning

0 absolutely useless

solution

1 very inadequate

solution

2 weak solution

3 tolerable solution

4 adequate solution

5 satisfactory solution

6 good solution with few

drawbacks

7 good solution

8 very good solution

9 solution exceeding

the requirement

10 ideal solution

6. DT8 – Evaluation Scales

22

Concept 1 2 3 4 5

Criteria

A: low material cost

3 1 4 4 3

B: easy of assembly

3 4 4 4 3

C: short testing time

4 1 3 4 4

D: simple construction

2 3 4 3 3

E: functional safety

2 2 2 2 2

F: simple operation

3 3 3 3 2

Total 17 14 20 20 17

Relative = Total/24

0.71 0.58 0.83 0.83 0.71

6. DT8 – 2nd Level Evaluation Matrices

23

WEIGHT

(0-4)

C1

(RUB ON

- RUB

OFF)

C2

(PLACE

ON -

TAKE

OFF)

C3

(PLACE

ON - RUB

OFF)

WORKING PRINCIPLE:

MAKES ERASABLE

MARK

4 4 4

REMOVES

ERASABLE MARK

4 3 3

EMBODIMENT:

HOLDS POINT 3 2 4

PRODUCTION:

FEW PARTS 4 3 2

SIMPLE TO MAKE 4 2 2

ASSEMBLY:

EASY 3 3

OPERATION:

COMFORTABLE TO

USE

2 2 3

LOW USE FORCE 3 3 4

MAINTENANCE:

SHARPENABLE 4 4 4

SAFETY:

DOESN’T HARM

USER BY

BREAKING INTO

SMALL, HARMFUL

PARTS

4 3 4

NOT POISONOUS 0 4 3

TOTAL POINTS:

6. DT8 – 3rd Level Evaluation Matrices

ME 2110: Creative Decisions and

Design 24

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