Differentiation and
Platform Architecting
ME 546 - Designing Product Families - IE 546
Timothy W. Simpson
Professor of Mechanical & Industrial
Engineering and Engineering Design
The Pennsylvania State University
University Park, PA 16802
phone: (814) 863-7136
email: tws8@psu.edu
http://www.mne.psu.edu/simpson/courses/me546
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© T. W. SIMPSON
Planning Product Platforms
• Robertson and Ulrich (1998) advocate a three-step approach:
1) Product plan – which products to offer when
2) Differentiation plan – how products will be differentiated
3) Commonality plan – which components/modules will be shared
Source: D. Robertson and K. Ulrich, 1998, "Planning Product Platforms," Sloan Management Review, 39(4), pp. 19-31.
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Differentiation Plan
for automotive example
Commonality Plan
for automotive example
Commonality Plan and Differentiation Plan
Source: D. Robertson and K. Ulrich, 1998, "Planning Product Platforms," Sloan Management Review, 39(4), pp. 19-31.
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Product Family Architecting
• Based on the commonality plan and differentiation plan,
an architecture must be developed for the platform and
family of products

If everything is the same,
then nothing is different
despite cost savings

If everything is different,
then costs skyrocket
• Trick: how to find the
best architecture to
balance the two
Source: D. Robertson and K.
Ulrich, 1998, "Planning Product
Platforms," Sloan Management
Review, 39(4), pp. 19-31.
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© T. W. SIMPSON
Platform Architecting
• The platform architecture will lead to a product family
with a given level of commonality and distinctiveness

Option A has low
commonality but
each product is
very distinctive

Option B has high
commonality but
products lack
distinctiveness

Option C has a
good balance of
commonality and
distinctiveness
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C
A
B
© T. W. SIMPSON
Commonality/Variety Tradeoff Angle
• Within a given industry do companies tend to apply the
same strategy: do they have the same trade-off angle,
a, between commonality
C
and variety?
A
• X. Ye & J. Gershenson
(Michigan Tech) argue
that they do and have
created the Product
Family Evaluation
Graph (PFEG) based
on this idea to provide
guidance for companies
in product family design
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a
a
B
a
© T. W. SIMPSON
Product Family Evaluation Graph (Ye, 2008)
• Compares alternative product families to determine
which family best meets a company’s strategic goals

Also good for product family benchmarking
• The tradeoff angle, a, is dictated by strategic impact
factors and a company’s competitive focus
 ideal
target
 realistic
goal for
company
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 actual
 target
tradeoff
© T. W. SIMPSON
Strategic Impact Factors – Marketing
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Strategic Impact Factors: Others
n
• Each factor is scored and weighted: S   (wi  I f )
i 1
and a is computed: a  f S 
i
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© T. W. SIMPSON
ecker
Power Tool Case Study
• Imagine you are
designing Delta’s
new power toolset

• The competition is
existing
toolsets
made by:
DEWALT®
® ®
DEWALT
Skil
PENNSTATE
Black & Decker
wi
Skil®
I fi
Si
wi
Delta®
I fi
Si
6
-1
-6
3
-1
-3
3
-1
-3
6
-1
-6
Customer needs
characteristics
1
-1
-1
1
-1
-1
1
-1
-1
1
-1
-1
Customer needs
Price consciousness
Quality consciousness
3
3
9
-1
-1
1
-3
-3
9
3
3
9
-1
-1
1
-3
-3
9
3
9
9
-1
-1
1
-3
-9
9
3
9
9
-1
-1
1
-3
-9
9
Level of pre- and post sales
service
6
1
6
6
1
6
6
1
6
6
1
6
Buyer power
Competitive intensity
9
6
1
1
9
6
6
9
1
1
6
9
6
6
1
1
6
6
3
6
1
1
3
6
Unique sets of customer
requirements
1
-1
-1
1
-1
-1
1
-1
-1
3
-1
-3
Development time
6
-1
-6
3
-1
-3
3
-1
-3
6
-1
-6
Product life-cycle length
and predictability
1
-1
-1
1
-1
-1
1
-1
-1
1
-1
-1
Maintenance and service
Automation level
Recycling
Financial condition
3
1
6
9
-1
-1
-1
1
-3
-1
-6
9
3
1
1
6
-1
-1
-1
1
-3
-1
-1
6
3
1
3
6
-1
-1
-1
1
-3
-1
-3
6
3
3
1
6
-1
-1
0
1
-3
-3
0
6
Distribution and supply
channel
3
-1
-3
3
-1
-3
3
-1
-3
3
-1
-3
SumDecker
=
Black &
®
Dewalt®
wi
I fi
Si
Stability and predictability
of demand levels

®
Black & Deck®
wi
I fi
Si
Factor
®
®
5
Skil
Competitors
Black and Decker®
®
DEWALT
®
®
Skil
Skil
13
2
ac
CDIC
CDIV
0.424
0.324
0.438
0.576 53.67°
0.676 64.42°
0.562 52.10°
-8
S
5
13
2
© T. W. SIMPSON
Determining a for Delta – Ideal vs. Actual
• Use linear regression to correlate S and a based on competition
65
60

DEWALT®
Delta
CDIC
CDIV a actual a ideal
0.22
0.78
®
74.3°
39.6°
55
ac
Black and
Decker®
Skil®
CDIV
50
45
1
40
0.78


FDelta
FDelta
®
®
35
-10
-5
0
S
5
10
15

PDelta , 39.6°
®
Company
®
Delta
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S target
-8
a
b
a
1.17
48.95
39.61°
a = -8×1.17+48.95 = 39.61
Pˆa
74.3
39.6°
0
0.22
74.3°
39.61
1 CDIC
© T. W. SIMPSON
PFEG Discussion
• Why the differences between estimated and actual?



• How else could we use PFEG?



• What do you think about the underlying assumption,
i.e., companies within a given industry tend to use a
similar commonality/variety strategy?



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© T. W. SIMPSON
Factors Affecting Platform Architecture
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
Customer requirements
Changing performance needs (including size, style, weight, etc.)
New environmental constraints (temperature, humidity, vibration, etc.)
New functions (due to new markets or new enabling technologies)
Reliability improvements
Reduce prices (cost reductions required)
Reduce amount of material
Change material type
Remove redundant components
Reduce assembly time
Use lower cost technology
Reduce serviceability requirements
Reduce serviceability time
Improve component manufacturing process
Regulations, standards, and so on
Changing government/industry regulations or standards
Competitor introduction of improved product (higher quality or lower price)
Obsolescence of parts
Source: Martin, M. V. and Ishii, K., 2002, "Design for Variety: Developing Standardized and Modularized Product Platform
Architectures," Research in Engineering Design, 13(4), pp. 213-235.
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Generational Variety Index
• GVI is an indicator of the amount of redesign required
for a component to meet future market requirements
• Process for calculating GVI:
Step 1:
Determine
market &
desired life
for platform
Step 2:
Create QFD
matrix
Step 4:
Estimate
engineering
metric target
values
Step 3:
List expected
changes in
customer
requirements
Step 5:
Calculate
normalized
target values
matrix
Step 6:
Create GVI
matrix
Step 7:
Calculate GVI
Source: Martin, M. V. and Ishii, K., 2002, "Design for Variety: Developing Standardized and Modularized Product Platform
Architectures," Research in Engineering Design, 13(4), pp. 213-235.
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What is Quality Function Deployment (QFD)?
• Developed by Japanese in 1970’s to provide a way to
propagate customer needs through product, part, and
process quality requirements using a series of maps

House of Quality helps translate “Voice of the Customer” into
specific engineering requirements
Source: J. R. Hauser and D. Clausing, 1998, "The House of Quality," Harvard Business Review, 66(3), pp. 63-73.
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Customer Attributes  Engineering Characteristics
Source: J. R. Hauser and D. Clausing, 1998, "The House of Quality," Harvard Business Review, 66(3), pp. 63-73.
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House of Quality (HOQ)
Source: J. R. Hauser and D.
Clausing, 1998, "The House of
Quality," Harvard Business
Review, 66(3), pp. 63-73.
The “roof” identifies any
relationships between the
Engineering Requirements
The “basement” identifies
specific targets for each
Engineering Requirement
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© T. W. SIMPSON
Generational Variety Index
• GVI is an indicator of the amount of redesign required
for a component to meet future market requirements
• Process for calculating GVI:
Step 1:
Determine
market &
desired life
for platform
Step 2:
Create QFD
matrix
Step 4:
Estimate
engineering
metric target
values
Step 3:
List expected
changes in
customer
requirements
Step 5:
Calculate
normalized
target values
matrix
Step 6:
Create GVI
matrix
Step 7:
Calculate GVI
Source: Martin, M. V. and Ishii, K., 2002, "Design for Variety: Developing Standardized and Modularized Product Platform
Architectures," Research in Engineering Design, 13(4), pp. 213-235.
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© T. W. SIMPSON
Example of GVI Computation
Expected range of change
over platform life
MTBF (hrs)
Volume flow rate (gal/min)
Depth (in)
Height (in)
Width (in)
Power consumption (W)
Cold water volume (gal)
Cost ($)
Fast cool down
Cold water
High capacity
Low energy usage
Compact
Fill cup quickly
Reliable
Low cost
EM Target Values
Current Market
Future Market 1
Future Market 2
Future Market 3
Water Temperature (C)
Cool down time (min)
• Consider the design of a water cooler
for current and three future markets:
x
M
L
M
M
L
M
L
M
100
100
125
80
Sep-00
Jun-01
Oct-01
Apr-02
x
x
x
x
x
x
x
x
x
120
120
90
120
10
10
10
10
0.5
0.5
0.8
0.5
75 12.5 13
50 12.5 13
75 12.5 13
75 10 13
13
13
13
10
0.5
0.5
0.8
0.5
15,000
15,000
15,000
15,000
Water
bottle
Reservoir
Insulation
T Heat
E sink Fan
C
Power supply
Water Cooler Chassis
(side view)
Source: Martin, M. V. and Ishii, K., 2002, "Design for Variety: Developing Standardized and Modularized Product Platform
Architectures," Research in Engineering Design, 13(4), pp. 213-235.
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GVI Matrices
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x
x
x
x
x
x
x
Fascia
1
Insulation
3
Reservoir
6
Plumbing
Power Supply
3
6
1
6
9
1
4
1
7
3
3
6
1
5
Fascia
x
Insulation
x
Reservoir
Power Supply
x
Plumbing
Thermo-Elec Cooler
x
Chassis
Heat Sink
Cool down time (min)
Water Temperature (C)
Cold water volume (gal)
Power consumption (W)
Width (in)
Height (in)
Depth (in)
Volume flow rate (gal/min)
MTBF (hrs)
Cost ($)
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
GVI Ratings
Chassis
Thermo-Elec Cooler
x
Engineering
Requirements
Components
Fan
Cost ($)
MTBF (hrs)
Volume flow rate (gal/min)
Depth (in)
Height (in)
Width (in)
Cold water volume (gal)
Water Temperature (C)
x
GVI Matrix
Cool down time (min)
Water Temperature (C)
Cold water volume (gal)
Power consumption (W)
Width (in)
Height (in)
Depth (in)
Volume flow rate (gal/min)
MTBF (hrs)
Cost ($)
GVI:
QFD Matrix II
x
Heat Sink
Fast cool down
Cold water
High capacity
Low energy usage
Compact
Fill cup quickly
Reliable
Low cost
Fan
Customer
Requirements
Cool down time (min)
QFD Matrix I
Power consumption (W)
Engineering Requirements
6
6
6
6
3
15
9
1
9
3
19
1
6
24
Rating Description
Requires major redesign of the component
9
(>50% of initial redesign costs)
6
Requires partial redesign of component (<50%)
3
Requires numerous simple changes (<30%)
1
Requires few minor changes (<15%)
0
No changes required
Note: Elements with higher GVI values will
require most redesign for future markets; so,
platform low GVI elements and embed
flexibility into/for high GVI elements
© T. W. SIMPSON