Three Views of Product
Development Complexity
Prof. Steven D. Eppinger
Massachusetts Institute of Technology
Sloan School of Management
Engineering Systems Division
Center for Innovation in Product Development
MIT
ESD
©2000 Steven D. Eppinger
eppinger@mit.edu
http://www.mit.edu/people/eppinger/
http://web.mit.edu/dsm
Lean Aerospace Initiative Plenary Conference
April 10, 2001
Information Density in Complex
Product Development
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400 people
5000 part numbers
2000 significant parts
125 subassemblies
2000 drawings
12,000 problems
~1,000,000 decisions
~1,000,000 info. flows
Office copier by Xerox
complex product = system
Three Perspectives to Study
Development of Complex Systems
• Product/System-level
• Process-level
Planning
• Organization-level
Concept System-Level
Development
Design
Detail
Design
Testing and
Refinement
Production
Ramp-Up
System Decomposition
• Decompose a complex system into subsystems and components
• Decompose a complex process into subprocesses and tasks
• Decompose a large organization into teams
and individuals
Decompositions Exhibit
Architectures
• The pattern of interactions between the
decomposed elements define the architecture
– System architecture
– Process architecture
– Organization architecture
Decompositions Exhibit
Architectures
• The pattern of interactions between the
decomposed elements define the architecture
– System architecture
– Process architecture
– Organization architecture
Potential Complexity Metrics
• The number of elements determines the
complexity of the decomposition
• The uncertainty of elements determines their
difficulty in development and integration
• The pattern of interaction among the elements
indicates the complexity of the architecture
• The alignment of the patterns determines the
difficulty of developing the system in context
Uncertainty of
Elements
Number of
Elements
?
Pattern of
Interactions
?
Alignment of
Patterns
An Approach to Studying the Patterns
• We can study the patterns of interactions in
three perspectives in order to better
understand system complexity:
– System example: Pratt & Whitney 4098 jet engine
– Process example: Intel semiconductor development
– Organization example: GM Powertrain organization
• We can also compare the patterns across the
perspectives:
– System vs. Organization example: Pratt & Whitney engine
– Process vs. Organization example: electrical connectors
System Architecture Example:
P&W 4098 Jet Engine
•9 Systems
•54 Components
•569 Interfaces
Design Interfaces:
•Spatial, Structural
•Energy, Materials
•Data, Controls
HPC
LPC HPT
FAN
B/D
LPT
Mechanical Components
Externals and Controls (2)
Modular Systems
Distributed Systems
Lessons Learned:
System Architecture
• Hierarchical system decompositions are
evident.
• System architecting principles are at work.
• There is a disparity between known interfaces
and unknown interactions.
• Integrating elements may be functional and/or
physical.
• Hypothesis: Density of known interactions–
novel
experienced
optimization
learning
sparse
mature
dense
clustered
Process Architecture Example:
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Set customer target
Estimate sales volumes
Establish pricing direction
Schedule project timeline
Development methods
Macro targets/constraints
Financial analysis
Develop program map
Create initial QFD matrix
Set technical requirements
Write customer specification
High-level modeling
Write target specification
Develop test plan
Develop validation plan
Build base prototype
Functional modeling
Develop product modules
Lay out integration
Integration modeling
Random testing
Develop test parameters
Finalize schematics
Validation simulation
Reliability modeling
Complete product layout
Continuity verification
Design rule check
Design package
Generate masks
Verify masks in fab
Run wafers
Sort wafers
Create test programs
Debug products
Package products
Functionality testing
Send samples to customers
Feedback from customers
Verify sample functionality
Approve packaged products
Environmental validation
Complete product validation
Develop tech. publications
Develop service courses
Determine marketing name
Licensing strategy
Create demonstration
Confirm quality goals
Life testing
Infant mortality testing
Mfg. process stabilization
Develop field support plan
Thermal testing
Confirm process standards
Confirm package standards
Final certification
Volume production
Prepare distribution network
Deliver product to customers
1 2
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Intel Semiconductor Development Process
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= Information Flows
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= Planned Iterations
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• = Generational Learning
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Lessons Learned:
Process Architecture
• Information flows describe the PD process
more completely than task networks.
• PDTs report their inputs more reliably than
their output flows.
• We find parallel and sequential stages within
the (CDIO) phases of the PD process.
• Planned iterations can be facilitated to
accelerate the process.
• Unplanned iterations require special attention
to make the process more robust.
Organization Architecture Example:
Engine Development
• Organization: General Motors Powertrain Division
• Product: “new-generation” engine (small-block V8)
• Structure: 22 PDTs involved simultaneously
Decomposition of the Engine
Development Project
22 PDTs
Design
Engine
Engine Block
Cylinder Heads
Camshaft/Valve Train
Pistons
Connecting Rods
Crankshaft
Flywheel
Accessory Drive
Lubrication
Water Pump/Cooling
Intake Manifold
Exhaust
E.G.R.
Air Cleaner
A.I.R.
Fuel System
Throttle Body
EVAP
Ignition System
Electronic Control Module
Electrical System
Engine Assembly
PDT composition
1 product release engineer
1 CAD designer
3 manufacturing engineers
2 purchasing representatives
2 casting engineers
machine tool supplier
1 production control analyst
1 financial planner
production personnel
PDT Interactions
Engine Block
Cylinder Heads
Camshaft/Valve Train
Pistons
Connecting Rods
Crankshaft
Flywheel
Accessory Drive
Lubrication
Water Pump/Cooling
Intake Manifold
Exhaust
E.G.R.
Air Cleaner
A.I.R.
Fuel System
Throttle Body
EVAP
Ignition
E.C.M.
Electrical System
Engine Assembly
A B C D E F G H
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System Team Assignments
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Air Cleaner
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Cylinder Heads
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E.G.R.
E.V.A.P.
Electrical System
Electronic Control
Ignition
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Accessory Drive
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A.I.R.
Throttle Body
Exhaust
E.G.R.
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Ignition
E.C.M.
Electrical System
Engine Assembly
A F G D E I B C J K P H N O Q L M R S T U
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Lubrication
Engine Block
Camshaft/Valve Train
Cylinder Heads
Intake Manifold
Water Pump/Cooling
Fuel System
Air Cleaner
Throttle Body
EVAP
Cylinder Heads
Intake Manifold
A.I.R.
Exhaust
E.G.R.
Accessory Drive
Ignition
E.C.M.
Electrical System
Engine Assembly
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Daily
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Team 4
Exhaust
E.G.R.
Team 3
Team 1
Pistons
Flywheel
Connecting Rods Engine Block
Lubrication
Crankshaft
Team 2
A.I.R.
Water Pump/
Cooling
Camshaft/
Valve Train
Cylinder Heads
Intake Manifold
E.V.A.P.
Fuel System
Air Cleaner
Throttle Body
Accessory Drive
Electrical System
Ignition
Engine Assembly
Electronic Control Module
Integration Team
PDT-to-System-Team Assignments
Lessons Learned:
Organization Architecture
• Organization architecture can also be mapped
in terms of interactions – across individuals
or PDTs.
• We usually find a (partial, at least) one-to-one
mapping from system decomposition to
organization structure.
• Organizations can be designed based on the
underlying technical structure of the system
being developed.
• Co-Evolution Hypotheses:
– Organizations evolve to address deficiencies in their
ability to implement the system architecture.
– System architectures evolve to address deficiencies in
the development organization.
Arch
Org
Comparing the System Architecture
to the Organization Architecture
Product Decomposition
into Systems
Development Organization
into Teams
Technical interactions
define the architecture
Team interactions
implement the architecture
How does product architecture
drive development team interaction?
Research Method: Mapping Design
Interfaces to Team Interactions
No
Team
Interaction
Design Interface Matrix
Yes
Yes
No
Design Interface
Resultant Matrix
Task assignment assumption: Each team designs one component
Team Interaction Matrix
Design Interfaces:
P&W 4098 Jet Engine
•9 Systems
•54 Components
•569 Interfaces
Design Interfaces:
•Spatial, Structural
•Energy, Materials
•Data, Controls
HPC
LPC HPT
FAN
B/D
LPT
Mechanical Components
Externals and Controls (2)
Modular Systems
Distributed Systems
Development Organization:
P&W 4098 Jet Engine
• 60 design teams clustered into 10
groups.
• Teams interaction intensity:
Low intensity interaction
High intensity interaction
– Capture frequency and importance of
coordination-type communications (scale from
0 to 5).
– Interactions that took place during the detailed
design period of the product development
process.
– Design executed concurrently.
Six system integration teams
Team Interactions
Overall Results
No
(2453)
Team
Interactions
Yes
(409)
228
(8%)
2225
(78%)
341
(12%)
68
(2%)
Yes
No
(569)
(2293)
Design Interfaces
We reject the null hypothesis that “team interactions
are independent of design interfaces”.
2 = 1208 >> Critical 2(0.99,1) = 6.635
Design Interfaces Not Matched by Team Interactions
No
(2453)
Team
Interactions
Yes
(409)
228
(40.1%)
(59.9%)
341
2225
68
Yes
No
(569)
(2293)
Design Interfaces
HYPOTHESES:
H1: Across boundaries, design interfaces are less likely to be
matched by team interactions.
H2: Weak design interfaces are less likely to be matched by
team interactions.
Effect of Organization/System Boundaries
No
Data set: 569 design interfaces
Team
Interactions
Yes
Yes
No
Design Interfaces
First criterion:
Design interfaces matched
by team interactions
59.9%
Design interfaces NOT
matched by team interactions
40.1%
Second criterion:
Design interfaces
WITHIN organizational
boundaries
78.8% are
matched
Design interfaces
ACROSS organizational
boundaries
47.8% are
matched
Effects of Organizational/System Boundaries
(modular vs. integrative systems)
No
Team
Interactions
Data set: 569 design interfaces
Yes
Yes
No
Design Interfaces
Overall:
Design interfaces
WITHIN organizational
boundaries
Design interfaces
ACROSS organizational
boundaries
78.8% are
matched
47.8% are
matched
36.4% of ACROSS
design interfaces
are matched
53.2% of ACROSS
design interfaces
are matched
Lessons Learned:
No
Team
Interactions
Architecture and Organization
Yes
Yes
No
Design Interfaces
• We can predict coordination-type communications by
studying the architecture of the product
– 83% of coordination-type communication were predicted
• Teams that share design interfaces may not communicate
when
– Design interfaces cross organizational boundaries
– Design interfaces are weak (within organizational boundaries)
– Teams communicate indirectly through other design teams (across
organizational boundaries)
• Teams that do not share design interfaces may still
communicate when
– Unknown design interfaces are discovered
– Design interfaces are system-level dependencies
Lessons Learned about
Development of Complex Products
• Product (system) complexity must be
considered in the context of the process and
organization which are developing it.
• Processes and organizations can be designed
to facilitate development of specific product
architectures.
• System concepts such as modularity and
architectural knowledge apply at the level of
sub-system interactions.