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After specifications phase, we have already committed ~40% of product cost!

Specification Development

% o

f p

rod

uc

t co

st c

om

mit

ted

Conceptual Design

Detailed design

Time

100

60

0

20

40

80

IMPORTANCE OF PROPER PROBLEM DEFINITION

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CONCEPTUAL DESIGN PHASE

1. Specification Development / Planning PhaseDetermine need, customer and engineering requirements

Develop a project plan

2. Conceptual Design PhaseGenerate and evaluate concepts

Select best solution

3. Detail Design PhaseDocumentation and part specification

Prototype evaluation

4. Production PhaseComponent manufacture and assembly

Plant facilities / capabilities

5. Service PhaseInstallation, use , maintenance and safety

6. Product Retirement PhaseLength of use, disposal, and recycle

Customer surveysCustomer interviewsQFD

Gantt chartsCPM

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CONCEPT GENERATION

Concept - is an idea that can be represented in a rough

sketch or with notes of what might someday be a product.

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If you generate one idea it will probably be a poor idea

if you generate twenty ideas then you might have one good idea

CONCEPT GENERATION

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So how do we generate those concepts?

Basic philosophy for generating concepts:

Form follows function

Creativity must be controlled by engineering judgment / expertise / experience

CONCEPT GENERATION

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CONCEPT GENERATION AND SELECTION

SUMMARY

NeedRequired

functionality

Concept 1

Concept 2

Concept 3

…

Concept n

QFD

Functional Decomposition

Morphological Analysis

Ideation

Brainstorming

Patents

Reference (Books, Trade Journals)

Experts’ help

Feasibility judgment

Technology readiness

Go/no go screening

Decision matrix method

Final concept

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SOURCES FOR CONCEPT IDEAS

1. Ideation

2. Brainstorming - a group oriented technique

3. Patents - extensive patent search may be required. (Note: there are over 5 million patents in the U.S.)

4. Reference books and trade journals - most reference books give analytical techniques and few design ideas

(Trade journals are a good source, but generally are targeted at specific disciplines).

5. Experts to help generate concepts - a good source of information are manufacturers catelogues (check the Thomas Registry).

6. Functional decomposition and morphological analysis

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1. Get a general idea of the design problem and develop different ways to tackle it

Do not worry about practicality

Do not refine ideas

2. Find feasible ideas

If only some elements of an idea work, extract them for inclusion in the next iteration

3. Pick, choose and recombine ideas

Using useful elements from all ideas

4. Refine

List three concepts and add elements you really need in the finished product

IDEATION

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Fundamental Principles of Brainstorming

1. Criticism is not allowed - any attempt to analyze, rejecty, or evaluate ideas is postponed until after the brainstorming session.

2. All ideas brought forth should be picked up by the other people - participants should seek ways of improving the ideas of others.

3. Participants should divulge all ideas that enter their mind - the wilder the idea, the better.

4. Provide as many ideas as possible within a relatively short time - the greater the number of ideas, the more likelihood of useful results.

BRAINSTORMING

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Brainstorming is an organized approach for producing creative ideas by letting the mind

think without interruption. Brainstorming can be done either individually or in a group; in

group brainstorming sessions, the participants are encouraged, and often expected, to

share their ideas with one another as soon as they are generated. The key to

brainstorming is not to interrupt the thought process. As ideas come to the mind, they

are captured and stimulate the development of better ideas.

An essential element of brainstorming is putting criticism 'on hold'. Instead of

immediately stating what might be wrong with an idea, the participants focus on

extending or adding to it, reserving criticism for a later 'critical stage' of the process.

By suspending judgment, you create a supportive atmosphere where participants

feel free to generate unusual ideas.

BRAINSTORMING

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Procedure for a typical brainstorming session

A meeting room is equipped with a flipchart, blackboard, or overhead projector placed in a prominent location.

Between six and twenty people with an interest in the subject (although not necessarily experts) are invited to participate.

Write on the flipchart (or blackboard) a statement of the subject or problem that will be discussed. This is often presented as a question.

Choose one person to write down the ideas generated. Ideas should be written concisely but without paraphrasing. The recorder should state the idea in the words she has written to ensure that it expresses the meaning intended by the originator.

Choose one person to facilitate the process. This involves encouraging participation by everyone and maintaining a criticism free, uninhibited atmosphere. Encourage even wild and seemingly ridiculous ideas.

After 5 to 20 minutes the facilitator ends the session Review the list from top to bottom to ensure everyone understands the ideas. Eliminate from the list any duplications. Remove any obviously ridiculous suggestions.

BRAINSTORMING

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PATENTS

In the 1920s, engineers at Sperry Gyroscope Company developed a clever design for a bearing that would hold the end of the gyro shaft in position with great accuracy both axially and laterally, would support the gyro, and would have low friction.

– It was patented and put into service with great success.

– However, in 1965 the same basic design was discovered in a notebook belonging to Leonardo da Vinci dating from about 1500.

[Ullman 1992]A low friction bearing from da Vinci's notebook.

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SOURCES FOR CONCEPT IDEAS

REFERENCE BOOKS AND TRADE JOURNALS

http://www.machinedesign.com/

http://www. sae.org/

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SOURCES FOR CONCEPT IDEAS – EXPERT HELP

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FUNCTIONAL DECOMPOSITION TECHNIQUE

Step 1: Find the overall function that needs to be accomplished.

Goal is to generate a single statement of the overall function based on the

customer requirements. All design problems have one or two "most

important" functions. These must be stated in a single concise sentence.

Example: portable kayak

Design a kayak that can be folded into a package small enough to fit in a

trunk of a car

Step 2: Decompose the function into subfunctions (perform functional decomposition). Goal is to refine the overall function statement as much as possible.

Guidelines:

1. Document what not how.

2. Use standard methods and notations whenever possible for describing subfunctions.

3. Consider the logical relationships between the functions to determine their sequence.

4. Match inputs and outputs in the functional decomposition.

5. Break the main function down as finely as possible using a block diagram.

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Foldable kayak

Customer requirements

Product functions satisfying customer requirements

FUNCTIONAL DECOMPOSITION TECHNIQUE

Allows reduction in size when transported and stored

unpack Use unpacked pack

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Decomposing top level function into subfunctions

First level decomposition

Second level decomposition

Third level decomposition

FUNCTIONAL DECOMPOSITION TECHNIQUE

Unfold skeleton

Pump up Assemble form smaller

components

... ... ...

unpack Use unpacked pack

unpack

Pump up

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Functional decomposition is used to identify the necessary product

functionality

Morphological analysis is used to explore alternative means and

combinations of achieving that functionality.

For each element of product function, there may be a number of

possible solutions. The morphological chart is prepared and used to

develop alternative combinations of means to perform functions and

each feasible combination represents a potential solution.

* Morphology: The science of the form and structure

FUNCTIONAL DECOMPOSITION TECHNIQUE

AND MORPHOLOGICAL ANALYSIS*

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Goal is to generate as many concepts as possible for each of the

functions identified in the Functional Decomposition process.

If there is a function for which only one conceptual idea exists,

then this function needs to be reexamined because there are very

few functions that can be fulfilled by only one concept).

DEVELOPING CONCEPTS FOR EACH FUNCTION

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Steps:

List product functions (functional decomposition)

List the possible 'means' for each function (morphological analysis)

Chart functions and means and explore combinations

DEVELOPING CONCEPTS FOR EACH FUNCTION

Unfold skeleton

Pump up Assemble form smaller

components

unpack

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Functional decomposition of a wood splitter – in class exercise

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COMBINING CONCEPTS INTO SINGLE CONCEPTUAL DESIGN

Concept 1Concept 2Concept 3Concept 4

Design concept

Function

hold on ice

Goal is to select one concept for each function and combine those selected into a single complete conceptual design.

Abstract concepts must now take some form, most often the form of sketches and comments.

secure

Concept 1Concept 2Concept 3Concept 4

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SKETCHES AND COMMENTS

Terminal cover assembly

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Assistive writing device.

– Rough sketches made in the design notebook provide a clear record of the development of the concept and the product.

SKETCHES AND COMMENTS

25Initial sketches and final design for a reusable syringe.

SKETCHES AND COMMENTS

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1. Develop a confident attitude.

[Buhl 1968]

SOME THOUGHTS ON CREATIVITY

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2. Unlock your imagination.

[Buhl 1968]

SOME THOUGHTS ON CREATIVITY

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3. Be persistant.

"Invention is 95% perspiration and 5% inspiration"

T. Edison

[Buhl 1968]

SOME THOUGHTS ON CREATIVITY

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4. Develop an open mind.

[Buhl 1968]

SOME THOUGHTS ON CREATIVITY

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5. Suspend your judgement.[Buhl 1968]

SOME THOUGHTS ON CREATIVITY

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6. Set problem boundaries.

[Buhl 1968]

SOME THOUGHTS ON CREATIVITY

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TECHNIQUES FOR EVALUATING CONCEPTUAL DESIGN

Feasibility

Judgment

Technology

Readiness Assessment

Go/no-go Screening

Decision Matrix Method

Numerous Concepts

Gut Feeling

State of Art

Customer Requirements

Absolute

Relative

Type of Comparison Technique Basis of Comparison

BEST CONCEPTS

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EVALUATION BASED ON FEASIBILITY* JUDGMENT

What we think about it?

Understanding + Experience

* Feasibility: The quality of being doable

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EVALUATION BASED ON TECHNOLOGY READINESS ASSESSMENT

Objective - is to determine the readiness of the technologies that may be used in the design concept. Immature technology will lead to a poor-quality product or cancellation of a project due to cost overruns.

Time-Line for Technology Readiness

Technology Development Time

Powered human flight 403 (1500 – 1903)

Photographic cameras 112 (1727 – 1839)

Radio 35 (1867 – 1902)

Television 12 (1922 – 1934)

Radar 15 (1925 – 1940)

Xerography 17 (1938 – 1955)

Atomic bomb 6 (1939 – 1945)

Transistor 5 (1948 – 1953)

Digital camera 30 1965 - 2004

High temperature super conductor ? 1987 - ?

Electric car 1900 - ?

…..

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EVALUATION BASED ON TECHNOLOGY READINESS ASSESSMENT

Six measures to determine if a technology is mature:

1. Can the technology be manufactured with known processes?

2. Are the critical parameters that control the function identified ?

3. Are the safe operating parameters known ?

4. Have the failure modes been identified ?

5. Does hardware exist that demonstrates positive answers to the above four questions ?

6. Is the technology controllable throughout the product's life cycle ?

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Displacement on Demand has been in works for the last 25 years…..

finally:

GM announces that the 2005 model year GMC Envoy XL, Envoy XUV and Chevrolet trailblazer EXT will be the first vehicles to showcase its innovative Displacement on Demand fuel-saving technology, which enhances fuel economy without compromising performance or the ability to carry heavy loads. Displacement on Demand is to be a standard feature in the vehicles' optional Vortec 5300 V-8 engine. The technology, which boosts the Vortec engine's fuel efficiency by 8 percent, is also to be introduced in other GM engines in the 2006 model year.

EVALUATION BASED ON TECHNOLOGY READINESS ASSESSMENT

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Hybrid car

EVALUATION BASED ON TECHNOLOGY READINESS ASSESSMENT

2000 2010

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http://www.veva.bc.ca/enfield/enfield1.jpg

2004

EVALUATION BASED ON TECHNOLOGY READINESS ASSESSMENT

http://www.dieselstation.com/pics/2011-Holden-Volt-car-pics.jpg

2010

Electric car

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EVALUATION BASED ON TECHNOLOGY READINESS ASSESSMENT

Film camera Digital camera