Quality Function
Deployment
(QFD)
Presented by
Angela Presberry
Mercena Johnson
History of QFD
• 1966 - Dr. Yogi Akao (Japan)
– Introduced Quality Function Deployment by
Kiyotaka Oshiumi, Bridgestone Tire
• 1972 - Dr. Shigeru Mizuno (Japan)
– Professor emeritus - Tokyo Inst. Of Technology
– First application was at the Mitsubishi/Kobe Shipyard
• 1977 – Toyota (Japan)
History of QFD…continued
• 1978 – First book written on QFD
– QFD: The Customer-Driven Approach to Quality Planning
and Deployment (1994 Quality Resources: ISBN92-8331122-1; written by Mizuno and Akao; translated by Glenn
Mazur) and QUALITY FUNCTION DEPLOYMENT:
Integrating Customer Requirements into Product Design
(Productivity Press: ISBN 0-915299-41-0; written by Akao;
translated by Glenn Mazur
History of QFD – Additional Article…
• Article titled:
– The leading edge in QFD: past, present and future
Author(s): Yoji Akao, Glenn H. Mazur
Journal: International Journal of Quality & Reliability
Management Year: 2003 Volume: 20 Issue: 1 Page: 20 - 35
DOI: 10.1108/02656710310453791
Publisher: MCB UP Ltd
History of QFD
• 1984 – Dr. Clausing (Xerox)
– Brought to the United states
• 1994 - First QFD book
– Translated into English
May I Introduce You to QFD?
Quality Function Deployment…
• “At the time, statistical quality control, which
was introduced after World War II, had taken
roots in the Japanese manufacturing industry,
and the quality activities were being
integrated with the teachings of such notable
scholars as Dr. Juran, Dr. Kaoru Ishikawa, and
Dr. Feigenbaum that emphasized the
importance of making quality control a part of
business management, which eventually
became known as TQC and TQM.”
Many aliases of QFD
• Quality Function Deployment is….
• Customer-Driven Engineering
• House of Quality
• Customer-Driven Project Design
• Voice of the Customer
• Decision Matrix
What is Quality Function Deployment?
• Quality Function Deployment (QFD) is a teambased planning tool used for fulfilling customer
expectations or requirements
•
•
•
•
Deployed through:
Product Planning
Assembly/Part Development
Process Planning
Process/Quality Control
Benefits of QFD
• Product Development/Implementation
time
• Product Quality
• Improves Customer Satisfaction
• Promotes Teamwork
Steps: Quality Function Deployment
1.
2.
3.
4.
5.
Identifying the Customer(s).
Determining Customer Req.
Prioritizing the Requirements.
Competition Benchmarking.
Translating the Customer Requirements into
Measurable Engineering Requirements
6. Prioritize Customer Requirements
Perfect Blueprint for Duality by design
Time Factor and Cost:
Design Change
Engineering Changes
Time to Market
Increases Quality
Four Phase Approach to QFD
QFD Exercise #1
• Benefits of Quality Function
Deployment (QFD)
QFD is…Customer Needs
• In order to begin the process
for building or forming a
House of Quality, one must
know what the customer
what wants & needs.
• The QFD process incorporates
the desires of the customer
into the design process. The
quality is built into the product
during manufacturing.
Voice of the Customer
•
•
•
•
This part of the design is most in depth
Quality is defined by the…CUSTOMER
What are their expectations?
Are their expectations uses to drive the design
process?
• What are some things the design team can do
to help achieve customer satisfaction?
Voice of the Customer…continued
• In many instances customer
requirements/expectations are not always
simple or easy to identify.
• The QFD Team will assist in identifying the
Technical Requirements as well.
QFD Team - Research
• QFD Team
– Composed many different individuals within the
organization
– Members come from many different disciplines
within the organization
– Members work together with the same objective
in mind, the customer
– It is important to make quality control a part of
business management
Customer Information
• Data can be collected in many
different ways
• Solicited, measureable and
routine
• Unsolicited, measurable, and
routine
• Solicited, subjective, and
routine
• Solicited, subjective, and
haphazard data
• Unsolicited, subjective and
haphazard data
Pg. 12-2 pp.320
Management Tools used
to Collect Data
• Affinity Diagram – (Figure 17-1 p. 446)
• Interrelationship Diagram (Figure 17-2 p. 445)
• Tree Diagram (Figure 17-3 p. 448)
* See Handouts
The Critics of QFD
•
•
•
•
•
•
QFD does not apply to every project
Unbalanced QFD team (members)
Priorities are not fully established
Too complex
Usually requires more money
Some believe that QFD is not useful to
for US businesses.
Japan vs. United States
• The United States & Japan have two different
ways of responding to business & customers;
usually respond to business and customers:
– React to the customer vs. respond to them
– Waste vs.
BREAK!!!!
Welcome to the House of Quality
• A product planning matrix that is developed in
Quality Function Deployment and shows the
relationship between what a customer wants and
how the firm that produces the product is going to
meet those wants.
• Increases cross functional integration within
organizations. (marketing, engineering, and
manufacturing)
• Considered by many to be the primary chart in
quality planning
Parts of the House of Quality
• First and most importance – Customer
Requirements (WHATs)
• Second – Technical Descriptors (HOWs)
• Third – Relationship between customers needs
and design attributes (WHATs vs. HOWs)
• Correlation Matrix (HOWs vs. HOW’s)
• Customer Competitive Assessment
• Technical Competitive Assessment (Set of weighted graphs)
• Engineering Measures
A company that
manufactures bicycle
parts wants to
expand their product
line by producing
handles for mountain
bikes.
Goal of any QFD team: To make
the product either more
appealing then it exists or what
the competition has or
introduce a need that the
customer is not expecting but
would appreciate
Correlation
6
Matrix
3
Technical Descriptors
5
1
4
Priority
Customer
Needs
7

Defines relationship
between customers
desires and the firms
product/product
capabilities
Customer
Relationships
between
Customer Needs
and
Design Attributes
Competitive
Assessment
Tec Technical Competitive Assessment
8
Engineering Measures
Key Element Voice of the Customer
 Spoken & unspoken (Why)
 How Important the Needs
(What’s) are TO THE
CUSTOMER
Need 1
Need 2
Need 3
Need 4
Need 5
Need 6
Need 7
Our Affinity Diagram
Aesthetics
Performance
Cost
Lightweight
Aerodynamic
Strength
Nice Finish
Durable
Corrosion Res
Primary
Secondary
Performance Aesthetics
Reasonable Cost
Aerodynamic Look
Nice Finish
Corrosion Resistant
Lightweight
Strength
Durable
Technical Descriptors (HOWs)
• The next step of the QFD process after
identifying what the customer wants is HOW!
• How can we satisfy these wants.
• Regulatory standards and requirements
dictated by management must be identified.
• Brainstorming
• Correlation between team and customer
critical
WHAT CUSTOMER
WANTS
HOW
HOW
HOW
HOW
HOW
HOW
HOW
HOW
HOW
HOW CAN WE ACCOMPLISH
Need 1
Need 2
Need 3
Need 4
Need 5
Need 6
Need 7
Keep to the voice of the Customer
Secondary
Powder Metallurgy
Forging
Sand Casting
Die Casting
Materials Selection
Welding
Titanium
Aluminum
Steel
Secondary
Primary
Manufacturing Process
HOW’s
vs.
WHAT’s
WHAT 1
WHAT 2
WHAT 3
WHAT 4
WHAT 5
WHAT 6
WHAT 7
HOW 7
HOW 6
HOW 5
HOW 4
HOW 3
HOW 2
HOW 1
Strength of the Interrelation
Between the What’s and
the How’s
● Strong
0 Medium
∆ Weak
• The relationship matrix shows us the
relationship between customer
requirements (WHATs) and Technical
Descriptors (HOWs)
• Customer requirements are translated
into engineering characteristics
(Technical Descriptors)
Steel
• Steel ranks strong in reasonable cost, strength
and durability in the relationship between
customer requirements and technical
Descriptors
• It ranks medium in nice finish
• It ranks weak in corrosion resistance and being
lightweight
• No relationship with aerodynamic look, leave
blank
 Aluminum ranks strong in relationship
between customer requirements and
technical descriptors in reasonable cost, nice
finish, corrosion resistant, and being
lightweight
It is medium in strength and being durable
It ranks weak in the aerodynamic
look
Titanium
• Titanium ranks strong in relationship
between customer requirements and
technical descriptors in nice finish,
corrosion resistant, lightweight and
strength
• It ranks medium in being durable
• It ranks weak in reasonable cost and
aerodynamic look
Welding
• Welding ranks strong in relationship between
customer requirements and technical
Descriptors as far as reasonable cost
• It ranks weak in aerodynamic look, nice finish,
corrosion resistant, strength and durability
• There is no relationship between welding and
being lightweight so leave blank
• Die Casting ranks strong in the relationship
between customer requirements and technical
descriptors in aerodynamic look and nice finish
and being durable.
• It ranks medium in cost and corrosion resistant
and strength
• There is no relationship between die casting and
being lightweight so leave blank
• Sand Casting ranks strong in the relationship
between customer requirements and
technical descriptors in reasonable cost
• It ranks medium in aerodynamic look and
corrosion resistant and being durable and
strength
• There is a weak relationship with nice finish
• There is no relationship between sand casting
and being lightweight so leave blank
Forging
• Forging ranks strong in the relationship
between customer requirements and
technical descriptors in strength and being
durable
• There is a medium relationship in
aerodynamic look, corrosion resistant , cost
and a nice finish
• There is no relationship between forging and
being lightweight so leave blank
Powder Metallurgy
• Powder Metallurgy ranks strong in the
relationship between customer requirements
and technical descriptors in aerodynamic look
and nice finish
• It ranks medium in being durable and
corrosion resistant
• There is a weak relationship with strength and
lightweight and reasonable cost
Points to Consider with Relationship Matrix
• If there are empty rows (horizontal)
Customer requirement has not been
met!
• If there are empty columns, (vertical)
then that particular technical descriptor
does not affect customer requirements
and may be removed from House of
Quality
Correlation Matrix (Roof)
HOW’S vs. HOW’S
Identifies interrelationship
between each technical
descriptor’s
● Strong Positive
○ Positive
X Negative
* Strong Negative
Interrelationship Matrix
• Next –Correlate the Interrelationship (Roof)
HOWS vs. HOWS
• The main function of the interrelationship
matrix is to establish a connection between
the customer’s product requirements and the
performance measures designed to improve
the product.
Steel
•
•
•
•
•
Steel is strong positive in Welding
Steel is positive in Die casting
Steel is strong positive in Sand Casting
Steel is strong negative in Forging
Steel is negative in Powder Metallurgy
Aluminum
•
•
•
•
•
•
Aluminum is:
Positive in Welding
Strong positive in Die Casting
Positive in Sand Casting
Negative in Forging
Positive in Powder Metallurgy
Titanium
•
•
•
•
•
•
Titanium:
It is a negative relationship in Welding
It is positive in Die Casting
It is a strong negative in Sand Casting
It is negative in Forging
It is a strong positive relationship in
Powder Metallurgy
Positive Correlation
Negative correlation
A strong positive
correlation would
be nearly perfect
correlation
(technical
descriptor’s
support each
other)
A strong negative
correlation mean
technical descriptor’s
do not support each
other
Conflicting Technical Descriptors can mean Tradeoffs
Using the QFD matrix lets you
acknowledge Tradeoffs in the
planning stage before actual
production
If tradeoffs not resolved they
can lead to customer unfulfilled
requirements, increased costs,
poorer quality, longer
production times
• Customers perception of product relative to
competition (collected data)
 Has customer requirements been met?
 What are areas to concentrate on?
 Where does our competition rank?
Our Product
3
4
4
4
3
3
3
This is how our
Product Ranked in
the Customer
Competitive
Assessment
Competition
• A’s Product
4
5
5
4
4
3
3
B’s Product
2
3
3
2
2
4
4
Technical Competitive Assessment
• Evaluation for Technical Descriptors
(HOWs vs. competitors HOWs)
• Assign ratings to each technical
descriptor (1= worst to 5 = best)
• Evaluation of competition helps to
highlight the absolute strengths and
weaknesses in competing products.
A’s
• Titanium
• Die Casting
B’s
• Steel
• Welding
Ours ?
Technical Competitive Assessment- Material
 Steel = (strong – cost, strength, durability)
(medium- finish) (weak -weight, corrosion
res.)
 Aluminum= (strong – cost, finish, corrosion
res. & weight) (medium- strength, durability)
(weak –look)
 Titanium =(strong – finish, corrosion res.
lightweight, strength) (medium-durable)(weak
– cost, look)
Technical Competitive Assessment
Steel Aluminum Titanium Welding Die-casting Sand Casting Forging Powder
OURS
0
5
A’s
0
0
B’s
5
0
0
0
5
5
0
5
0
4
0
0
0
0
0
0
0
0
0
0
Technical Competitive Assessment
Ours
• Aluminum
• Die Casting
A’s
• Titanium
• Die Casting
B’s
• Steel
• 80% Welding
Prioritized Customer Requirements
• Customer rankings determine the base that
requirements are prioritized.
1. Importance to Customer
2. Target Value
3. Scale-up Factor
4. Sales Point
5. Absolute Weight
Focus Team Information
(ranks relative importance to customer)
•Useful for prioritizing efforts and trade-off decisions
Team may have different priorities
8
5
5
2
7
5
3
Rank each customers requirement
by assigning it a value- 10 the
highest -1 the least importance
Our focus team states:
Cost ranks 8 out of 10
Lightweight is 7 out of 10
Aerodynamic Look, Finish, Strength
are medium at a 5 out of 10
Durable is 3 out of 10
Corrosion Resistant is 2 out of 10
Target Value
This is the column where the QFD Team
decides if they want to:
 keep their product unchanged
 improve the product
 or make the product better then what
the competition does.
Cost
+1
Look
Finish
Corrosion Res.
Lightweight +1
Strength
Durable
3
4
4
4
3
3
3
Cost
Look
4
Finish
Corrosion Res.
4
Lightweight
Strength
Durable
4
4
4
3
3
Scale-Up Factor
• The ratio of target value to the product rating
given in the customer competitive
assessment.
• The question is what level is the product on
now and what is the target rating? Is the
distance within reason? The higher the
number, the more effort is needed.
• Sometimes there is not a choice due to
difficulties in reaching target. Therefore the
target has to be reduced to attainable levels.
Scale –Up Factor
Cost
1.3
1
1
1
Weight
1.3
1
1
• Ratio of target value to the product
rating given in the customer
competitive assessment
• In this case, Cost and Lightweight
had a product rating of 3 and the
target value is 4 so scale-up factor is
1.3
• The other items are multiplied by 1
to show no further target value
Sales Point Weight for Marketability
1.5
1.5
1
1
2
1
1
• How well a Customer Requirement will Sell
• Object- Promote the Best Customer
Requirement and any other of the
customer requirement that will help in the
sale of the product
• Sales Point is a value between 1.0 and 2.0
with 2.0 being the Highest
• In this case, lightweight is the strongest at 2
• The cost and Aerodynamic look rank 1.5
• The rest are 1 as they do not factor in sale
Absolute Weight
(Importance to the Customer x Scale-Up factor x Sales Point) =
Absolute Weight
After summing all the absolute
weights, a percent and rank for each
customer requirement can be
determined.
16
8
5
2
18
5
3
The weight can then
be used as a guide for
the planning section of
the product
development
Prioritized Technical Descriptors
• This is a block of rows in the foundation of
the house corresponding to each technical
descriptor. These contain degree of technical
difficulty, target value and absolute and
relative weights. The QFD team identifies
technical descriptors that are most needed to
fulfill customers expectations and need
improvement
Engineers and trained personal provide objective
data:
Uncover gaps in engineering
 Enable designers to seek opportunities for
improvement
 Links QFD to a company’s strategic vision and
allows priorities to be set in the design process.
Points to Consider
Team should consider:
•
•
•
•
•
•
•
Available technology
Technical characteristics
Cost
Schedule
Supplier/subcontractor capability
Manufacturing capabilities
Personnel qualifications
Probability Factor
Probability factors represent the
perceived possibility of achieving
each how. A low possibility factor
can indicate that a current solution
will not be competitive. Probability
factors are used to weigh each
HOW and affect the final QFD
results
Degree of Technical Difficulty
This step provides objectives that guide the design, objectively assesses progress
1
6
9
4
7
3
6
9
Least Difficult = 1 to Most Difficult = 10
Example- The degree of difficulty for Die Casting is 7
and the degree of difficulty for Sand Casing is 3 because
it is a much easier manufacturing process-
This is a objective measure that defines
values that must be obtained to achieve the
technical descriptors .
How much it takes to meet or exceed the
customers expectations is answered by
evaluating all the information entered into
the House of Quality and selecting target
values
5
5
5
4
5
0
0
0
Absolute Weight
Weights assigned to relationship matrix times Importance to Customer
• Translate symbol into numbers
• Example – Aluminum is
for reasonable
cost.
=9
• Corresponding row in Importance to Customer
is 8
(9 x 8)+(1 x 5)+(9 x 5)+(9 x 2)+(9 x 7)+(3 x 5)+(3 x 3) =
227
Absolute weight for aluminum is 227
Relative Weight
Weights assigned to relationship matrix times Absolute Weight
• Translate symbol into numbers
• Example – Aluminum is
for reasonable
cost.
=9
• Corresponding row in Absolute Weight 16
• (9x16)+(1x8)+(9x5)+(9x2)+(9x18)+(3x5)+(3x3) =
401
Relative Weight for Aluminum is 401
•
•
•
•
•
•
•
•
Steel
Aluminum
Titanium
Welding
Die Casting
Sand Casting
Forging
Powder Metallurgy
168
251
227
401
193
92
162
122
132
125
303
167
213
203
165
171
Customer and Design Requirements
• Higher absolute and Relative ratings
identify areas where engineering efforts
need to be concentrated
• Handlebars will involve:
• Aluminum for the material
• Die Casting for the process
Design Requirements
Component Requirements
3
Process Operations
Component
Requirements
2
Design
Requirements
Customer
Requirements
1
4
Quality Control Plan
The How’s at One
Level Become the
What’s at the Next
Level
References
DR. RICK EDGEMAN, PROFESSOR & CHAIR – SIX SIGMA
BLACK BELT Department of Statistics University of Idaho
TOTAL QUALITY MANAGEMENT DALE BESTERFIELD,
CAROL BESTERFIELD-MICHINA, GLEN BESTERFIELD,
MARY BESTERFIELD-SACRE 2003
KIPP REYNOLDS STUDENT EASTERN UNIVERSITY 2007
& more references…continued
http://www.emeraldinsight.com/Insight/viewContentItem.do;jsessionid
=4A35EB0C93A1577398BF1C0135644E01?contentType=Article&hdAction=
lnkpdf&contentId=840587
http://www.qfdi.org/what_is_qfd/history_of_qfd.htm