These are the Skills You Need to
Build a House – What’s Missing?
1
What You Need is the Architecture!
Where does the
plumbing go?
What is the function
of each room?
How is the wiring
laid out?
What rooms should
be clustered?
What rooms should
not be adjacent?
What rooms should
interconnect?
What about the
HVAC layout?
2
The Architecture Provides The Plan
The architecture answers these
questions:
• How can the functions be grouped?
• How should the groups be arranged?
• What interconnections are necessary?
• What isolations are necessary?
3
PRODUCT ARCHITECTURE
Sources:
• Ulrich KT and Eppinger SD, Product Design and
Development, 3rd ed., McGraw Hill, 2004
• Reinertsen DG, Managing the Design Factory: A Product
Developer’s Toolkit, Free Press, 1997
4
Elements of Products
• Functional elements: individual operations
and transformations that contribute to the
overall performance of the product
– often combined into modules
• Physical elements: the parts, components,
and sub-assemblies that ultimately implement
the product’s functions.
5
What is Product Architecture?
• The scheme by which the functional
elements of the product are arranged
into physical chunks (modules) and by
which the physical chunks interact (at
interfaces).
Interface
Module A
Module B
6
Product Development Process
Planning
Concept
Development
System-Level
Design
Platform
decision
Concept
decision
Decomposition
decision
Detail
Design
Testing and
Refinement
Production
Ramp-Up
Product architecture is determined early in the development process.
7
Product Architecture: Definition
The arrangement of functional elements into
physical chunks which become the building
blocks for the product or family of products.
module
module
module
module
Product
module
module
module
module
8
Primary Types of Product
Architecture
• Modular
• Nonmodular (Integral)
Most products have some degree of modularity!
9
Modular Architecture
• Chunks (modules) implement one or several
elements
• Interactions between chunks (at interfaces)
– must be well-defined
– fundamental to the primary functions of the
product
• Modular architecture - allows a design
change in one chunk (module) without
requiring changes to other chunks (other
modules)
10
Modular Product Architectures
• Characteristics: 1) Chunks (modules) implementing
one or a few functions entirely, and 2) well-defined
interactions between chunks (interfaces).
Swiss Army Knife
Sony Walkman
11
Examples
• Video Games
– Modular: gaming systems (e.g.
GameCube)
– Integrated: stand-alone arcade games
• Power Supplies
– Modular: power bricks
– Integrated: on-board power converter
Types of Modularity
• Slot- modular architecture
• Bus- modular architecture
• Sectional-modular architecture
13
Slot-Modular Architecture
• each interface between chunks different various chunks cannot be interchanged
• example: automobile radio - implements exactly
one function, but interface different from any
other components in the vehicle
14
Bus-Modular Architecture
• a common bus to which chunks connect
via the same type of interface
• examples: track-lighting, shelving
system with rails, expansion card for PC
15
Sectional-Modular
Architecture
• all interfaces of same type, but no single
element to which all other chunks attach
• assembly built by connecting chunks to
each other via identical interfaces
• examples: piping systems, office
partitions
16
Modular Architecture of
the Sony Walkman
17
Trailer Example:
Modular Architecture
box
protect cargo
from weather
hitch
connect to
vehicle
fairing
minimize
air drag
bed
support
cargo loads
springs
suspend
trailer structure
wheels
transfer loads
to road
A 1-to-1 correspondence between modules and functions.
18
Advantage of Modular Design:
HP products are designed to be recycled. Recycling
design features include:
• Modular design to allow components to be removed, upgraded
or replaced
• Eliminating glues and adhesives, for example, by using snap-in
features
• Marking plastic parts weighing more than 25g according t ISO
11469 international standards, to speed up materials
identification during recycling
• Reducing the number and types of materials used
• Using single plastic polymers
• Using molded-in colors and finishes instead of paint, coatings or
plating
• Relying on modular designs for ease of disassembly of
dissimilar recyclable materials
http://www.hp.com/hpinfo/globalcitizenship/environment/productdesign/endoflife.html
Integral Architecture (Nonmodular)
• Functional elements of the product are
implemented using more than one chunk
• A single chunk implements many functional
elements
• Interactions between chunks ill-defined, may
be incidental to the primary functions of the
products
• Used with products with highest possible
performance in mind
20
Trailer Example:
Integral (Nonmodular) Architecture
upper half
protect cargo
from weather
lower half
connect to
vehicle
nose piece
minimize
air drag
cargo hanging
straps
support
cargo loads
spring slot
covers
suspend
trailer structure
wheels
transfer loads
to road
21
What is this?
Nail Clippers?
Ford Taurus
Integrated Control Panel
Other Examples
• Modular architecture
– Xerox copier
– Personal computer
– Residential AC units
• Singular (nonmodular) architecture
– Table knife
– High-performance transmission
– Precision-ground bearings
25
Integral vs. Modular
•
•
•
•
•
Integral
Higher system
performance
Lower system cost
(in large volume)
Tightly coupled
design teams
Expensive Tooling
Hard to change
•
•
•
•
•
Modular
Changeability
Decoupled design
teams
Reduced
performance
Requires flexible
manufacturing
Cheaper at low
volumes
Establishing the Architecture
To establish an architecture:
1. create a schematic of the product
2. cluster the elements of the schematic to
achieve the types of product variety
desired.
3. define the interfaces
27
The Concepts of Integral and
Modular Apply at Several Levels
• system
• sub-system
• component
28
Product Architecture =
Decomposition + Interactions
• Interactions
within chunks
• Interactions
across chunks
29
Schematic For A Wristwatch
Source: www.ulrich-eppinger.net
30
Schematic For A Telephone Base
Source: www.ulrich-eppinger.net
31
Product Architecture Example:
Hewlett-Packard DeskJet Printer
32
DeskJet Printer Schematic
Enclose
Printer
Print
Cartridge
Provide
Structural
Support
Functional
or Physical
Elements
Position
Cartridge
In X-Axis
Store
Output
Position
Paper
In Y-Axis
Store
Blank
Paper
“Pick”
Paper
Flow of forces or energy
Flow of material
Flow of signals or data
Accept
User
Inputs
Display
Status
Control
Printer
Supply
DC
Power
Communicate
with
Host
Command
Printer
Connect
to
Host
33
Cluster Elements into Chunks (Modules)
Enclosure
Enclose
Printer
Print
Cartridge
Provide
Structural
Support
Chassis
Functional
or Physical
Elements
Position
Cartridge
In X-Axis
Store
Output
Position
Paper
In Y-Axis
Store
Blank
Paper
“Pick”
Paper
Paper Tray
Print
Mechanism
Chunks
User Interface Board
Accept
Display
User
Status
Inputs
Control
Printer
Communicate
with
Host
Connect
to
Host
Logic Board
Power Cord
and “Brick”
Supply
DC
Power
Command
Printer
Host Driver
Software
34
Geometric Layout
logic
board
user interface board
print
cartridge
The 3-D Schematic
paper tray
print
mechanism
chassis
enclosure
print cartridge
height
roller
paper
logic board
paper tray
chassis
35
Incidental Interactions
User Interface
Board
Enclosure
Styling
Paper Tray
Vibration
Thermal
Distortion
Chassis
Print
Mechanism
RF
Shielding
Thermal
Distortion
Logic
Board
Host Driver
Software
RF
Interference
Power Cord
and “Brick”
36
Product Architecture Objectives
• Product architecture can be optimized
to achieve certain economic objectives
– Development Expense
– Unit Cost
– Product Performance
– Development Schedule
37
Using Product Architecture to
Achieve Economic Objectives
Three key factors to consider when using
architecture to achieve economic objectives
1. How modular to make the product (if at all)
2. How to handle variability within the system
3. How to manage the internal interfaces
38
1. Product Architecture and
Modularity
• Two economic objectives most affected
by modularity:
– Lower development expenses
• Modules separated from each other except at
the interfaces; internal workings immaterial
• Modules can be reused (no new development,
no new testing)
– Lower development cycle time
• Modularity permits concurrent development
39
The Dark Side of Modular
Architecture
• Cost
– Interfaces don’t come for free
• Usually require connectors, couplings, flanges, lines of code;
may require special attention to tolerances and alignment
• Performance
– Interfaces are potential bottlenecks
– Modular system performance is usually less than with a
tightly coupled, nonmodular system
• Mechanical systems: weak spot is usually the interface, not the
components
• Electrical systems: connectors often limit bandwidth or
reliability
40
Product Architecture --The End
41