Ppt for educational purpose

1. Product Architecture and
Modularity
Systems Engineering
MG587
Karl T. Ulrich and Steven D. Eppinger
3rd Edition, Irwin McGraw-Hill, 2004.

2. Product Architecture: Definition
The arrangement of functional elements into
physical chunks which become the building blocks
for the product or family of products.
Product
module
module
module
module
module
module
module
module

3. Other terms for “Chunks”
• A ‘Chunk’ is made up of a collection of components
that carry out various functions/sub-functions of
the product.
• Other terms for “Chunks” or elements that make
up a chunk
– Subsystem
– Cluster
– Module
– Building blocks
• ‘Interfaces’ connect these chunks together.

4. Architecture
• The Architecture of a product is the
scheme by which the functional elements
of the product are arranged into physical
chunks and by which the chunks interact.

5. Planning
Product Development Process
Concept
Development
System-Level
Design
Detail
Design
Testing and
Refinement
Production
Ramp-Up
Product architecture is determined early in the development process.
This is not a linear, sequential process.
Platform
decision
Concept
decision
Decomposition
decision

6. Architecture Decisions
Functional
Elements
Interfaces
Modularity
Product
Platform,
Variety
Cost and
Manufactura
bility
Physical
Elements
Product
Development
Management
Architecture
Decisions

7. Choosing the Product Architecture
Architecture decisions relate to product
planning and concept development decisions:
– Product Change (copier toner, camera lenses)
– Product Variety (computers, automobiles)
– Standardization (motors, bearings, fasteners)
– Performance (racing bikes, fighter planes)
– Manufacturing Cost (disk drives, razors)
– Project Management (team capacity, skills)

8. How Does Architecture Happen?
• Ulrich and Eppinger – ‘Chunks’ approach.
• MIT – Design Structure Matrix.
• Buede – Decomposition,
– Physical mirrors Functional structures.
• Dominant Flow Heuristics - R. B. Stone

9. Architectures: Challenge X
Provide
Transportation
Energy
Materials
Information
Transportation
Emissions

10. Modular or Integral Architecture?
Motorola StarTAC
Cellular Phone
Rollerblade
In-Line Skates
Ford
Explorer
Apple
iBook

11. Modular Product Architectures
• Chunks implement one or a few functions entirely.
• Interactions between chunks are well defined.
• Modular architecture has advantages in simplicity
and reusability for a product family or platform.
Swiss Army Knife Sony Walkman

12. Trailer Example:
Modular Architecture
box
hitch
fairing
bed
springs
wheels
protect cargo
from weather
connect to
vehicle
minimize
air drag
support
cargo loads
suspend
trailer structure
transfer loads
to road

13. Trailer Example:
Integral Architecture
upper half
lower half
nose piece
cargo hanging
straps
spring slot
covers
wheels
protect cargo
from weather
connect to
vehicle
minimize
air drag
support
cargo loads
suspend
trailer structure
transfer loads
to road

14. Integral Product Architectures
• Functional elements are implemented by multiple
chunks, or a chunk may implement many functions.
• Interactions between chunks are poorly defined.
• Integral architecture generally increases
performance and reduces costs for any specific
product model.
Compact Camera

15. Ford Taurus
Integrated Control Panel

16. Discussion Question
• Is one type of product architecture
(modular vs. integral) better than the
other?
– Performance
– Platforms
– Serviceability
– Interfaces
– Cost to manufacture
– Cost to develop

17. Steps to Establish the Product
Architecture – Ulrich and Eppinger
1. Create a functional model or schematic of
the product.
2. Cluster the elements on the schematic.
3. Make Geometric Layouts to achieve the
types of product variety.
4. Identify Interactions
– Fundamental (must interact)
– Incidental

18. Step 1: Functional or Schematic Diagram
• Physical and/or
Functional
• Connect Elements
Which Have
Fundamental
Interactions
• Show “Motion” &
“Flow”
Example: Rapid Prototyping
Machine using laser sintering

19. Step 2: Cluster Elements into Chunks
• Reasons to Cluster
– close geometric
relationship
– function sharing
– modular
– desire to outsource
Atmospheric
Control Unit
Laser Table
Powder Engine
Control
Cabinet

20. Step 3: Produce Geometric Layout
Note: If you can’t make a geometrical layout then go back
and redefine chunks and identify interactions

21. Step 4: Identify Interactions
• Forces consideration of geometric
interfaces to accommodate flows
• Illustrates possible problems caused by
interactions
– Fundamental
• Lines on the schematic that connect chunks
• Usually a well understood property
– Incidental
• Usually not shown on schematic
• Higher order effects/interferences

22. Product Architecture Example:
Hewlett-Packard DeskJet Printer
Part of a portfolio architecture and is composed of parts within a
product architecture

23. DeskJet Printer Schematic
Flow of forces or energy
Flow of material
Flow of signals or data
Store
Output
Store
Blank
Paper
Enclose
Printer
Provide
Structural
Support
Print
Cartridge
Position
Cartridge
In X-Axis
Position
Paper
In Y-Axis
Supply
DC
Power
“Pick”
Paper
Control
Printer
Command
Printer
Connect
to
Host
Communicate
with
Host
Display
Status
Accept
User
Inputs
Functional
or Physical
Elements

24. Cluster Elements into Chunks
Store
Output
Store
Blank
Paper
Enclose
Printer
Provide
Structural
Support
Print
Cartridge
Position
Cartridge
In X-Axis
Position
Paper
In Y-Axis
Supply
DC
Power
“Pick”
Paper
Control
Printer
Command
Printer
Connect
to
Host
Communicate
with
Host
Display
Status
Accept
User
Inputs
Paper Tray Print
Mechanism
Logic Board
Chassis
Enclosure
User Interface Board
Host
Driver
Software
Power Cord
and “Brick”
Functional
or Physical
Elements
Chunks

25. Geometric Layout
print
mechanism
paper tray
user interface board
print
cartridge
logic
board
chassis
chassis
paper
roller
print cartridge
paper tray
enclosure
logic board
height

26. Incidental Interactions
Enclosure
Paper Tray
Chassis
Print
Mechanism
User Interface
Board
Logic
Board
Power Cord
and “Brick”
Host Driver
Software
Styling
Vibration
Thermal
Distortion
Thermal
Distortion
RF
Interference
RF
Shielding

27. Dominant Flow Heuristics
• Heuristic 1: “The set of sub-functions
through which a flow passes, from entry or
initiation of the flow in the system to exit
from the system or conversion of the flow
within the system, define a module.”
Function
System
Energy
Material
Informa
tion

28. Generic Dominant Flow Illustration
Interface
Interaction
Material
Energy

29. Dominant Flow Example
• Fragment of the iced tea brewer FM
import
solid
store
solid
filter, tea
secure
solid
import
solid
store
solid
ice
secure
solid
import
human
force
human force
import
electricity
actuate
electricity
electricity regulate
electricity
convert
elect.to
therm.ener.
transmit
therm.ener.
transport
liquid
export
liquid
regulate
gas-flow
mixsolid
& liquid
refine
liquid
import
liquid
transport
liquid
water
store
liquid
stop
liquid-flow
human force
human force
human force
tea,
filter
heat
ice
ice
transport
liquid
therm. ener.
filter,
tea
filter,
tea
h.f. h.f.
h.f. h.f.
ice ice
water
water
water
water
h.f.
elect.
elect.
water
water water
tea,
filter
t.e. t.e.
t.e.
tea
tea
filter, used
tea
steam
t.e.
therm.
ener.
t.e.

30. Branching Flow
• Heuristic 2: “Parallel function chains
associated with a flow that branches
constitute modules. Each of the modules
interfaces with the remainder of the
product through the flow at the branch.”

31. Generic Branching Flow Illustration
Interface
Material
Module/Chunk #1
Module/Chunk #2
Branch

32. Branching Flow Example
• Fragment of the iced tea brewer FM
import
solid
store
solid
filter, tea
secure
solid
import
solid
store
solid
ice
secure
solid
import
human
force
human force
import
electricity
actuate
electricity
electricity regulate
electricity
convert
elect.to
therm.ener.
transmit
therm.ener.
import
liquid
transport
liquid
water
store
liquid
stop
liquid-flow
human force
human force
human force
tea,
filter
ice
transport
liquid
filter,
tea
filter,
tea
h.f. h.f.
h.f. h.f.
ice ice
water
water
water
water
h.f.
elect.
elect.
water
tea,
filter

33. Conversion-Transmission Modules
• Heuristic 3: A conversion sub-function or
a conversion-transmission pair or proper
chain of sub-functions constitutes a
module.
transmit
(transport)
flow B
convert
flow A to
flow B
function
flow B
conversion-transmission chain
… …

34. Conversion-Transmission Example
• Fragment of the iced tea brewer FM
import
solid
store
solid
filter, tea
secure
solid
import
solid
store
solid
ice
secure
solid
import
human
force
human force
import
electricity
actuate
electricity
electricity regulate
electricity
convert
elect.to
therm.ener.
transmit
therm.ener.
transport
liquid
export
liquid
regulate
gas-flow
mixsolid
& liquid
refine
liquid
import
liquid
transport
liquid
water
store
liquid
stop
liquid-flow
human force
human force
human force
tea,
filter
heat
ice
ice
transport
liquid
therm. ener.
filter,
tea
filter,
tea
h.f. h.f.
h.f. h.f.
ice ice
water
water
water
water
h.f.
elect.
elect.
water
water water
tea,
filter
t.e. t.e.
t.e.
tea
tea
brewed
filter, used
tea
steam
t.e.
therm.
ener.
brewed brewed
t.e.

35. The Design Structure Matrix (DSM):
An Information Exchange Method
Interpretation:
• Task D requires information from
tasks E, F, and L.
• Task B transfers information to tasks
C, F, G, J, and K.
Donald V. Steward, Aug. IEEE Trans. on Eng. Mgmt. 1981
Note:
• Information flows are easier to
capture than work flows.
• Inputs are easier to capture than
outputs.

36. DSM (Partitioned, or Sequenced)
Note:
Manipulate the matrix to emphasize features of the process flow.
Sequential, parallel and coupled tasks can be identified.
Clustering
Algorithms

37. System Team Assignment
Based on Product Architecture
F G E D I A C B1 K1 J P N Q R B2 K2 O L M H S T U V
Crankshaft F F l l l l l l l l l l l l
Flywheel G l G l l l l
Connecting Rods E l E l l l l l l
Pistons D l l l D l l l l l l l l
l
Lubrication I l l l l I l l l l l l l l l
Engine Block A l l l
l l A l l l
l l l
l l l l
Camshaft/Valve Train C l l l l C l l l l l l
Cylinder Heads B1 l l l
l l B1 l l l l l
l
Intake Manifold K1 l l l
l K1 l l l l l
Water Pump/Cooling J l l l l l l J l l l
l l l
l l l
Fuel System P l
P l l l l l l l l l l
Air Cleaner N l
N l l
l l l
l
Throttle Body Q l l l Q l l l l l l l
l l
EVAP R l l R l l l
Cylinder Heads B2 l l l
B2 l l l l
l l l
l
Intake Manifold K2 l l l l l l K2 l l l l l l l
A.I.R. O l l l l l l O l l
l l l l
Exhaust L l l l l l
l l l L l l l l l l
E.G.R. M l l l l l l l
l M l l
l l l
Accessory Drive H l l
l l
l l l l l l l
l l l l l H l l l l
Ignition S l l l l
l l l l l
l l
l l l l l S l l l
E.C.M. T l l l l l l l l l l l l l l l l l
l T l l
Electrical System U l l l l l l l l l l l l l l
l l l
l l U l
Engine Assembly V l l l l l l l l l l l l l
l l l l l l l l l V
Frequency of PDT Interactions
l Daily l Weekly l Monthly
Team 1
Team 2
Team 3
Team 4
Integration
Team
From “Innovation at the Speed of Information”, S. Eppinger, HBR, January 2001.

38. Modularity
• Modularity is a product development
strategy in which interfaces shared among
components in a given product architecture
become specified and standardized to allow
for greater substitutability of components
across product families.

39. Types of Modular Designs
• Slot
• Bus
• Sectional
• All retain a 1-to-1 mapping of functional to
physical elements

40. Modular vs. Integral
• Modular • Integral

41. Example of Modularity
K. Ulrich, “The Role of Product Architecture in the Manufacturing Firm” Research Policy,
24, 419-440 (1995)

42. Example of Modularity
K. Ulrich, “The Role of Product Architecture in the Manufacturing Firm” Research Policy,
24, 419-440 (1995)

43. Example of Modularity
K. Ulrich, “The Role of Product Architecture in the Manufacturing Firm” Research Policy,
24, 419-440 (1995)

44. Sony Walkman

45. Product Model Lifetime
From Sanderson and Uzumeri,
The Innovation Imperative, Irwin 1997.
0 1 2 3 4 5
Survival Time (years)
1.0
0.8
0.6
0.4
0.2
0
Fract ion
Surviving Sony
AIWA
Toshiba
Panasonic
Sony
1.97 yr
Others
1.18 yr
Average Life
About 200 versions
of the Sony Walkman
from four platforms!

46. Platforms and Modularity

47. Some Modularity Benefits
• Production of a great variety of end products
from a limited number of building blocks
• Platform strategy permitting many product
variants based on a stable architecture
• Facilitate changes to current and future products
• Simplifies parallel testing
• Serviceability
• Allows for parallel development of design teams
• Allows for outsourcing

48. Some Limitations to Modularity
• Cannot discriminate look alike products
• Increases the risk of competitors copying
designs
• Generally increases unit cost ( more
components), volume (size) or weight of the
product
• More interfaces are less reliable (why??)
• Depends on the capabilities of designers

49. Impact of Modularity Decisions on Later
Design Processes

50. Product Architecture Example:
Hewlett-Packard DeskJet Printer

51. Planning a Modular Product Line:
Commonality Table
Differentiation versus Commonality
Trade off product variety and production complexity

52. Planning a Modular Product Line:
Differentiation Table
Differentiation versus Commonality
Trade off product variety and production complexity

53. Supply Chain Issues
of Postponing
Differentiation

54. Examples of Postponing Differentiation
• Paint in Hardware Store
• Cake in Grocery Store
• Your experiences….

55. Product Configurators
• Satisfy customer demand by creating a
product composed of a number of pre-
defined components
• Select and arrange parts to fit product
and operational constraints
• Requirements:
– Modularization
– Custom assembly operations
– Up-front engineering and testing

56. Fundamental Decisions
• Integral vs. modular architecture?
• What type of modularity?
• What type of interfaces?
• How to assign functions to chunks?
• How to assign chunks to teams?
• Which chunks to outsource?

57. Product Architecture: Conclusions
• Architecture choices define the sub-systems and
modules of the product platform or family.
• Architecture determines:
– ease of production variety
– feasibility of customer modification
– system-level production costs
• Key Concepts:
– modular vs. integral architecture
– clustering into chunks
– planning product families