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• The design process is an engineering activity that turns a concept into reality.

• The process from concept to solution is not random. It is a logical sequence of steps to develop the best solution to a specific problem.

The Design Process

• The design process is not a one-way street ending in the finished product.

• It is a series of stages and check-points where each step in this process can be reviewed and analyzed. Modifications or refinements can be made to the concept.

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The Engineering Design Process

Develop Concepts(Conceptual Design)

Embody Design(Preliminary Design)

Detail Design(Detail Design)

Clarify Problem(Problem Definition)

Societal Need

Product that meetsneed

Report Design(Design Communication)

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Develop Concepts

Embody Design

Detail Design

Clarify Problem

Societal Need

Product that meetsneed

Design Phases Review

• Clarify the problem

(Problem Definition)– Gather customer needs

– Formulate Design Problems

– Form engineering requirements (QFD)

– Form PDS

Design Communication

Clarifying the Problem-Problem Defintion

Why is this initial phase of design so important???

Wouldn’t it be better to just start thinking of solution concepts?

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Design and the Customer• The result of the execution of the design

process is a new product, process or system

• Identification of need starts from customer’s suggestions or requests

• Final design must satisfy customer requirements or exceed expectation

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Design and the Customer• If customer requirements are not clear,

engineers must consult with customers• Customers must be informed of the design

status at all times• Both design team and customers may have

to modify their requirements in order to meet time, cost, performance and manufacturing constraints

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Kano Model• Normal Requirements are typically what we get by

just asking customers what they want.• Expected Requirements customer requirements

are simply expected by the customer and assumed to be available. For example, if coffee is served hot, customers barely notice it. If it's cold or too hot, dissatisfaction occurs. Expected requirements must be fulfilled.

• Exciting Requirements are difficult to discover. They are beyond the customer's expectations. For example, if full meals were served on a MAS flight from K.L to Senai, that would be exciting. If not, customers would hardly complain.

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Customer Satisfaction

Kano Model [Noriaki Kano 1984].

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The Overall Goal

The Overall Goal

• Increase customer satisfaction

=• Increase business success

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Example of Kano Model

• New electric –powered barbeque grill• Design team starts from existing successful

design basic• Customer may specify performance-related

items such as ease of cleaning, ease of setting the controls; cooking time, cooking effectiveness

• New concept, such as programmable cooking cycle, can give unexpected bonus to customer, make it selling point and create excitement.

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1. Identification of a Need

• Usually other than the engineer decides that a need exists

– Products have life cycle. New profitable products must be developed

– The consumers are ultimately the judges of whether there is truly a need; any product that doesn’t satisfy customers are doomed

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1. Gather raw data from customers

– Interviews

– Focus groups

– Observing product in use

1. Identification of a Need

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Meeting With The Customers

Proposed Outcomes Prioritized Outcomes

Prioritized Design Variables

Validated Outcomes & New Outcomes

Soft to Hard Information• Customer’s statements

(+ other raw data on problem)

• Customer’s needs

• Functional and Design requirements

• Technical Specifications

Example For MP3 player

Customer Statement

CustomerNeed

DesignRequirements

Easy to carry around

• Lightweight• Small in size• Ergonomic Shape

• Weight < 250gm• Size < 100x25x100mm.

• 9 of 10 people surveyed must state that device is “easy to carry”

• Example customer needs:

– Easy to use, Look good, Inexpensive, Fast, Light, Everything fits, Accurate

• Example engineering requirements– Costs less than $40.00 to manufacture– 8 of 10 users say that it is attractive or very

attractive– Assembles in less than 4 minutes– Requires maintenance less than once/year– Will operate in a marine environment for 10 years– Mass of less than 5 kg.– Provides user with feedback concerning the data

they entered

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Mission Statement

Product Description: ----

Key Business Goals: ----

Primary Market: ----

Secondary Market(s)? ----

Assumptions: ----

Stakeholders: ----

2. Project Definition

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2. Problem Definition

Solving the Wrong Problem

to reduce auto accident fatalities, using lap and shoulder belts were required

The solution technique that was implemented was an interlock system that requires the belts be latched before the auto could be started

Driver’s attitude was the real problem; it failed

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3. Search

• Locating, applying, and transferring information; lots of information is needed

• Open to many alternative solutions

• Gathering information may help for a better definition of the problem and a better solution

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• Type of Information– What has been written about it?– Is something already on the market that

may solve the problem? (already patented?)

– What is wrong with the way it is being done?

– What is right the way it is being done?

3. Search

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Type of Information

Who manufactures the current ‘solution’?

How much does it cost?

Will people pay for a better one if it costs more?

How much will they pay (or how bad is the problem)?

3. Search

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3. Search; Source of Information

• Existing solutions; reverse engineering

• Internet search

• Library search

• Government documents

• Professional organizations

• Trade journals

• Vendor catalog

• From experts

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4. Constraints• There could be many solutions, but there

are physical and practical limitations (constraints)– Examples– Market competition

• Too expensive– Legal restriction– Environmental Constraints– Size, weight etc.

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4. Constraints; Example

• Example hospital bed• Cost must not exceed RM2,500• Must meet safety codes• Must accommodate room size of 5 X 6

metres• Must be freestanding and cannot affect

the existing structure of the room

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5. Criteria

• Criteria are desirable characteristics of the solution which are established from experience, research, market studies, and customer preferences

• Criteria are used to judge alternative solutions on a qualitative basis, unless quantitative evaluation by mathematical model is available

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5. Criteria; cont’

• Weighting factor for criteria• Typical design criteria

– Cost– Reliability– Weight (either heavy or light)– Ease of operation and maintenance– Appearance– Compatibility

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5. Criteria; cont’

Typical design criteriaSafety featuresNoise levelEffectivenessDurabilityFeasibilityAcceptance

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6. Alternative Solutions

• It is just like selecting the best person among the candidates for a new management position. A list of candidates must be made for interview and review processes

• Likewise we need a list of possible answers to our problem before selecting the best one

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6. Alternative Solutions; cont’• Brainstorming

– The leader states the problem clearly and ideas about its solution are invited

– About 4-8 works well

– Free expression is essential; no discouraging word, no evaluation during brainstorming about the idea

– The leader sets the tone and tempo of the session and provides a stimulus when things begin to drag

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6. Alternative Solutions; cont’

Brainstorming (cont’)

The members of the group should be equals; no reason to impress or support any other member

Recorders are necessary

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7. Analysis• In order to find the best solution in light of

available knowledge and criteria, we must analyze the alternative solutions to determine performance capability

• Use of mathematical and engineering principles

• The goal is to obtain quantitative information for the decision step in the design process

• The time required to produce an analysis is critical

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8. Decision

• There may be no perfect one solution

• Trade-offs; many alternatives to satisfy criteria

• Decision is very hard part

• You need information in order to evaluate each alternative against each of the criteria

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8. Decision; cont’

• Analysis can provide basis for decision

• If time and money permits, experiment or prototype can help

• Poor research, a less than adequate list of alternatives, or inept analysis would prevent good decision

• Decision making is an art and a science

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9. Specification; cont’

• Database; cont’– Written notes, standards, specifications,

and so on, concerning quality and tolerances

– A complete bill of materials• Local or national codes and standard must

be satisfied• Utilize written, spoken, and graphical

language in order to develop and interpret specifications

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9. Specification• After designing, it must be clearly defined to

others in detail specifically

• Drawings, database, bill of materials

– A sufficient number of databases describing the size and shape of each part

– Layouts to delineate clearance and operational characteristics

– Assembly and subassemblies to clarify the relationship of parts

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10. Communication

• Great emphasis nowadays

• Selling your design and idea

• If your design is superb, you have to convince other people

• Written report & presentation.

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Contributions of Design to the New Products Process

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Design

1. The only way to learn about design is to do design

2. In engineering design, 3 types of knowledge are used: i) generate ideas

ii) evaluate ideas

iii) structure the design process

3. Not a clear-cut/scientific or rational process

4. Creativity and imagination

5. Broad understanding of physical world

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30%

15%

50%

5%

Overhead

Labor

Material

Design

Design Cost as Fraction of Manufacturing Cost

Labour

Overhead

Material

Design

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Design Cost Commitment

About 90% of the cost of producing a product is committed during the design phase (Ullman) 1-2.b.

Adapted from Ullman, 1997, The Mechanical Design Process, McGraw-Hill.

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The Cost of Change

• The cost of changing the basic design of a product increases rapidly as the design advances through the development cycle

Conceptual modeling $1

Detail design $10Prototype/test $100Manufacturing $1,000Product release $10,000

Source: Wohlers associates

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Develop Concepts

Embody Design

Detail Design

Clarify Problem

Societal Need

Product that meetsneed

Design Phases Review

• Develop Concepts

– Generate Concept Variants

• Basic: Morphological Analysis

• Design by Analogy,TRIZ

– Evaluate concepts

Design Communication

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Develop Concepts

Embody Design

Detail Design

Clarify Problem

Societal Need

Product that meetsneed

Design Phases Review

• Embody Design

• specifying the form of the product

• Generate an overall layout (i.e., Product Architecture)

Design Communication

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Develop Concepts

Embody Design

Detail Design

Clarify Problem

Societal Need

Product that meetsneed

Design Phases Review

Detail the layouts– Ensure compatibility between

sub-systems– Choose appropriate parameters

• Standards (government or controlling safety board)

Design Communication

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Engineering Designers typically follow these steps:1. Understand their customer's needs

(requirements).2. Establish design objectives (specifications) to

satisfy a given set of customer attributes. Define the problem they must solve to satisfy these needs.

3. Create and select the solution through synthesis.4. Analyze and optimize the proposed solution5. Check (validate) the resulting design against the

customer's needs.6. Implement the selected design

Conclusions