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WELCOME TO THE FIFTH LECTURE
Quality Function Deployment
QFD
House of Quality (HOQ)
Where we are
•
•
•
•
•
We have seen how to define the problem
We have seen how to decompose it
We have seen how to be creative
We have seen how to evaluate solutions
Now how can we improve on existing
products? - What does the CUSTOMER
want?
QFD:Definition
QFD stands for Quality Function Deployment.
Derived from six Chinese/ Japanese characters:
1. Hin shitsu: Qualities, features or attributes
2. Ki no: function
3. Ten kai: deployment
QFD:- systematic way for developing
products based on the needs of the
customer.
History of QFD
qOriginally developed by Yoji Akao of Tokyo in
1966.
qFirst implemented at the Kobe Shipyard of
Mitsubishi in 1972.
qSubsequently adopted by Toyota and other
Japanese Firms.
qFirst QFD Training outside Japan at GM and
Ford in 1972.
qLater by other companies around the world
QFD : QUALITY FUNCTION DEVELOPMENT
GOAL:
•Recognize the correlations between the customer
requirements and the product characteristics
•Identify the product characteristics that affect
specific customer requirements
•Recognize the correlations within the engineering
characteristics
QFD : QUALITY FUNCTION DEVELOPMENT
Paper by Hauser and Clausing in Harvard
Business Review 1988 prompted the
introduction of the Japanese House of
Quality into US companies.
Quality:
• Basic (unspoken, assumed) expected, typical
• Performance (spoken) one dimensional,
market research results
• Excitement (unspoken, the customer does not
know s/he wants it) pleasant, surprises or
delights customer
QFD : QUALITY FUNCTION DEVELOPMENT
10 Cash drains that reduce quality and productivity:
1. Technology
push, where is the pull?
•Lots of effort to generate technology without identifying need
•Great concepts developed, never integrated into a system
•Companies need strategies for technology development
•Make sure technology is mature enough before integrating
2. Disregard
the Voice of the Customer (VOC)
•Often hear voice of the engineer, not customer
•Solution: House of Quality (HOQ, QFD)
3. Eureka concept
•Too quickly grasping the first concept that comes along
•If alternatives are explored, insufficient evaluation techniques are
used
•Often driven by deadlines
4.
Pretend Design
•Deadline driven
•no planning, get to prototype, we‘ll fix it.
QFD : QUALITY FUNCTION DEVELOPMENT
5. Pampered product
•Products optimized for a set of parameters, not well over range
•Need to determine the „vital“ few parameters (Taguchi)
6. Hardware swamp
•Labs full of equipment that cant be maintained and used => too much
useless or meaningless evaluation
•Solution: maximum 4 iterations on prototype
7. Here is the product, where is the factory?
•Cannot design product independent of manufacturing
•Develop processes along with parts
8. We have always done it this way
•Very common mindset
•It has worked before - Sol: look at ways to optimize
9. Inspection
•Looking at parts at the end of the process does not lead to better
products
•Inspect throughout the process
10. Give me a target, and let me do my thing…
•American: Individual effort
•Final systems do not integrate well
•Management techniques for team approaches
QFD
# design
changes
US
Japan
HOUSE OF QUALITY
Before
How/
How
After
How
what what/How
Howmuch
How/
Howmuch
why
what/
why
QFD
Preparation stage inside a QFD-team
( In novel design, conduct in Market Study)
• Market segmentation / establishment of customer goals
• Collecting customers’ opinions, reports from
conferences and fairs, service reports, test reports,
patents, internet searches, internal goals and
experiences:
– Strengths weaknesses
– Wishes, requirements, suggestions
– Trends
• Sort, group
• Classification of the criteria in solution independent
requirements
• Building the House of Quality
Success of QFD
Market Needs:
q Present day Market is competitive and is consumer
driven
q A need to know what the customer wants
QFD asks and answers:
q What do customers want and need?
q Are all wants and needs equally important ?
q How can the information around a product be changed?
q How does one change affect other changes?
q How do you communicate the changes to the customers?
Why QFD?
Tangible Benefits
Intangible Benefits
qMajor Reduction in
Development Time
qVirtual elimination
of Late engineering
changes
qEnhanced Design
reliability
qEconomical factory
controls
q Increased customer
satisfaction
q Stable QA planning activity
q QFD documentation
package
- Often applies to generic
family
- Transferable storehouse of
engineering know - how
q Basis for Improvement
planning
RESPONSES
I
N
P
U
T
S
A
1 M
2 W
B
C
M
D
E
M
S
4
S
S
5 M
S
F
G
W
H
3
M
W
S = Strong ; M = Medium ; W = Weak
Assign num.values: S = 9 ; M = 3 ; W = 1
Four Phase Manufacturing QFD Process
Product Planning
Design Requirements
Customer
Requirements
Parts Deployment
Part Characteristics
Design
Reqts
Process Planning
Manufacturing Requirements
Part
Char
Production Planning
Production Operations
Mfg.
reqts
QFD
++
House of Quality
++
Engineering
Weights 2
Attributes 1
CorrelationMatrix 4
Points
Strong relationship
9
Assessment 5
Medium relationship
3
Targets 6
Weak relationship
1
techn. Competition compar. 7
customer's view 8
Characteristics 3
W1
W2
...
Customer
Ex.: 1-10
Competition compar. In
...
EC 2
EC 1
Ex.: 1-10
CA 1
CA 2
...
Goal-Conflicts 9
-
EXAMPLE
Priority
9
9
3
1
3
3
1
1
70
186
61
62
1
2
1
4
3
5
Goal
9
.....
Engraving ability
9
Our product
9
9
1
3
Competitor 2
5
10
5
4
1
5
Competitor 1
Easy to erase
Writes forever
Feels good in hand
Will not leak
Not easy to lose
Cost
.....
Design / Color
Customer Attributes
Lead material
Body material
E. Characteristics
Erasor
• Caution: oversimplified!
• And only top level considered!
• Check publications
7
4
6
3
3
7
5
4
4
4
3
6
5
4
7
3
3
5
7
6
7
6
8
8
(ref. von Helbling Management)
QFD Analysis
“Potential for Use of a House of Quality
Matrix Technique in Rehabilitation
Engineering”
by: Logan, G.D. & Radcliffe, D.F.
IEEE Transactions on Rehabilitation
Engineering
Introduction
•Goal: Improve wheelchair seating
to people with disabilities.
• Acquired customer requirements through
interaction with patients, and videotaped
sessions.
• Case 1: improving controls on wheelchair
• Case 2: attaching oxygen tank to wheelchair
Case 1 H.O.Q.
Conclusion
•Case 1 results:
– H.O.Q. provided accurate results.
– Top 3 ranked items lead to a
successful product and had
considerably higher totals than the
remaining engineering features.
Case 2: H.O.Q.
Conclusion
•Case 2 results:
• H.O.Q. did not include every aspect
necessary for a successful design.
• Customer requirements must be
gathered from primary and secondary
users and contain detailed info.
Conclusion: Summary Value of QFD
qStrengthens current development process
- Clear targets defined early based on
market/business demands
- simultaneous focus on product and process
technologies
- key issues remain visible for prioritizing resource
allocation
- communication and teamwork are enhanced
qDesired output efficiently achieved
- Products meet customer needs
- Products provide a competitive edge
ë QFD INTENTIONS
ì Cross Functional Teams
ì Development of a new product , service, or process
ì Refining an existing product , service, or process
ì Team fills out a House of Quality
ì Define the Voice Of the Customer
å rows on the left
ì Define the Performance Measures
å columns on the top
å Engineering Characteristics
å Technical Quality Characteristics
å Quality Specifications
å Functional Requirements
å The “Hows”
ì Forces creative thinking and continual evaluation of progress
ë QFD FORMAT HOQ
Interactions
Performance
Measures
Customer
Needs
Correlations
Planning
Matrix
Criticality (in Benefit Points)
Cost to Accomplish
Ratio (Benefit/Cost)
ë QUESTIONS ARE RAISED
ì Very tedious
å Still worthwhile
ì How
do we interpret our results
å After QFD…now what?
ì Build more houses
ì This leads to Matrix Hell
ë MATRIX
HELL
Customer Needs
Performance Measures
Performance
Measures
Features and
Technologies
Manufacturing Processes
Parts Specifications
ì Using QFD to “deploy”
the VOC throughout the
development process
å One is not enough
Features and
Technologies
Parts Specifications
ë UNREALISTIC
ì Initial HOQ takes 2 - 6 days
to complete
ì Exhaustion after first HOQ
Customer Needs
Performance Measures
Features and Technologies
Performance Measures
40 - 60 columns
Parts Specifications
Features and
Technologies
Manufacturing Processes
Parts Specifications
ì Eager to get to design
ì Substitute a design matrix
for second house
ì 80 - 90% of learning
occurred in the initial HOQ
15 - 20 rows
ë ANSWERS?
ì Specify area of concentration
å Identify top concerns and address them
å Eliminate the easy tasks
ì Assign specific tasks
å Identify an owner
å Create an owner or a joint owner
å Communication, communication,
communication
ë ANSWERS?
ì Performance Measure Analysis
å Who owns the measure?
å What is the current value of the measure?
å What should be the target value of the measure?
å What can be done to move the measure toward
the target value?
å What resources would it take in both time and
money to move the measure?
å What would the likely impact be on our cost per
unit to include the kind of feature or solution required
to move the measure? And what would it do to the
selling price that the customer would have to pay?
ë ANSWERS?
ì Formal Cost Benefit analysis
å Utilities or Benefit points
å Develop a ratio of benefit vs. associated cost
ì An example
å Benefit A - 8000
å Benefit B - 1500
å Cost A - $4,000,000
å Cost B - $500,000
å Ratio A - 2.0
å Ratio B - 3.0
A
B
Criticality (in Benefit Points)
Cost to Accomplish
Ratio (Benefit/Cost)
ë SUMMARY
ë Identifying the Customers
Needs is critical
Customer Needs
ë The initial house is the critical
beginning
Performance Measures
ë Decide whether one is enough - maybe two
ë Decisions
ë PMA
ë Cost Analysis
QFD software
• QFD Capture (free evaluation
download)
• http://www.gsm.mq.edu.au/cmit/
• German, Excel, …
FMEA (Failure Mode and Effect Analysis)
With the FMEA method, risks can be localized,
their probabilities and consequences estimated,
and precautions taken to prevent problems from
happening.
Different constitutencies:
System-FMEA
Design-FMEA
Conceptual phase
Design phase
System- FMEA
–
–
–
–
Customer
Customer service
Marketing
Process
specialists
– Development
team
Process-FMEA
Realisation
Design- FMEA
- Customer service
- Calculations
engineers
- Manufacturing
specialists
- Assembly personnel
- Development team
Test phase
Process- FMEA
- Customer
- Inspector/Q
- Development team
FMEA: ORGANIZATION OF FUNCTIONS
Step 1: Generating a functional tree
Function 1
Function 1.1
Function 1.2
Function 1.3
OverallFunction
Function 3
Function 6
Function 3.1
Function 3.1.1
Function 3.1.2
Function 2.2
Function 2.1
Function 2
Function 4.1
Function 4
Function 5
EXAMPLE FUNCTION TREE
Provide rotation
activate head
Move head
Accelerate
Seal
engage
Rotate
drehen
Brake
CD
Player
Stop
suction
Seal
Function 2.2
Function 2.1
Funktion 2
Step 2: for each Function
identify and localize extreme
risks and dangers:
Function 4.1
Function 4
Function 5
what happens, when ......?
which failures can happen ?
what are the consequences, when.....?
FMEA ANALYSIS
Step 3: Determining sources, controlling consequences, weighting
FMEA
FUNCTION:
Pot. failure Pot. failure reason
Effects
A B E RPA Action
A:
Probability of occurance
B:
Seriousness of consequences
E:
Probability of detection
Values :
1......10
Compare to limit x : RPA > x
Date
responsible A B E RPA*
RPA = A*B*E
Actions, so that RPA* < x
FMEA
• Function / component / process step
• Lists of parts to be analyzed and/or process
steps. Indicate how functions are fulfilled.
• Within the framework of the error analysis,
the following steps are executed for every
function of the part and/or every process. The
results are entered in the corresponding
column of the reply form
FMEA
Column 1: Potential failure
• All conceivable types of failures must be entered for
the individual part or process.
• Check list (incomplete):
•
•
•
•
•
•
•
•
•
Functional performance general
Deformation
Fatigue
Dissolution
Misalignment
Clamps
Corrosion
Dirt entry
Attrition
FMEA
Column 2: Cause of failure
All conceivable failure causes are assigned to every potential
failure. The description of the error causes must guarantee that
corresponding correcting-measures can be determined.
Check list (incomplete):
•
•
•
•
•
•
•
•
•
•
•
Component failure
Defective assembly
defective maintenance
false acceptances, specifications
false dimensioning
defective construction
defective Material
Quality problems in the manufacturing process
False heat treatment
false operation
defective measurement
false instrument
FMEA
Column 3: Effect of failure
• Starting point is the actual occurrence of the failure.
The implications of the failure on the customer and/or
user.
• Check list (incomplete):
•
•
•
•
•
•
•
•
Function not accomplished
Accident of different severity
complicated assembly or disassembly
weakening of the component (leading to rupture?)
Noise pollution
complicated repair
Pollution
unpleasant appearance
FMEA
• Useful and systematic approach to
failure identification and mitigation.
• Web sites have downloadable software
1/--pages
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