1 These are the Skills You Need to Build a House – What’s Missing?

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These are the Skills You Need to Build a House – What’s Missing?

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What You Need is the Architecture!

What is the function of each room?

What rooms should interconnect?

Where does the plumbing go?

How is the wiring laid out?

What rooms should not be adjacent?

What rooms should be clustered?

What about the HVAC layout?

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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?

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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

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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.

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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).

Module A Module B

Interface

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PlanningPlanning

Product Development Process

ConceptDevelopment

ConceptDevelopment

System-LevelDesign

System-LevelDesign

DetailDesign

DetailDesign

Testing andRefinement

Testing andRefinement

ProductionRamp-Up

ProductionRamp-Up

Product architecture is determined early in the development process.

Platform decision

Concept decision

Decomposition decision

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Product Architecture: DefinitionThe 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

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Primary Types of Product Architecture

• Modular• Nonmodular (Integral)

Most products have some degree of modularity!

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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)

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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

Examples

• Video Games– Modular: gaming systems (e.g.

GameCube)– Integrated: stand-alone arcade games

• Power Supplies– Modular: power bricks– Integrated: on-board power converter

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Types of Modularity

• Slot- modular architecture

• Bus- modular architecture

• Sectional-modular architecture

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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

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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

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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

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Modular Architecture of the Sony Walkman

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Trailer Example:Modular Architecture

box

hitch

fairing

bed

springs

wheels

protect cargofrom weather

connect to vehicle

minimizeair drag

supportcargo loads

suspendtrailer structure

transfer loadsto road

A 1-to-1 correspondence between modules and functions.

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

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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

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Trailer Example:Integral (Nonmodular) Architecture

upper half

lower half

nose piece

cargo hangingstraps

spring slotcovers

wheels

protect cargofrom weather

connect to vehicle

minimizeair drag

supportcargo loads

suspendtrailer structure

transfer loadsto road

What is this?

Nail Clippers?

Ford Taurus Integrated Control Panel

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Other Examples

• Modular architecture– Xerox copier– Personal computer– Residential AC units

• Singular (nonmodular) architecture– Table knife– High-performance transmission– Precision-ground bearings

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

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Establishing the Architecture

To establish an architecture:1. create a schematic of the product2. cluster the elements of the schematic to

achieve the types of product variety desired.

3. define the interfaces

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The Concepts of Integral and Modular Apply at Several Levels

• system

• sub-system

• component

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Product Architecture = Decomposition + Interactions

• Interactions

within chunks

• Interactions

across chunks

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Schematic For A Wristwatch

Source: www.ulrich-eppinger.net

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Schematic For A Telephone Base

Source: www.ulrich-eppinger.net

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Product Architecture Example:Hewlett-Packard DeskJet Printer

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DeskJet Printer Schematic

StoreOutput

StoreBlankPaper

EnclosePrinter

ProvideStructuralSupport

PrintCartridge

PositionCartridgeIn X-Axis

PositionPaper

In Y-Axis

SupplyDC

Power“Pick”Paper

ControlPrinter

CommandPrinter

Connectto

Host

CommunicatewithHost

DisplayStatus

AcceptUser

Inputs

Flow of forces or energy

Flow of material

Flow of signals or data

Functionalor PhysicalElements

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Cluster Elements into Chunks (Modules)

StoreOutput

StoreBlankPaper

EnclosePrinter

ProvideStructuralSupport

PrintCartridge

PositionCartridgeIn X-Axis

PositionPaper

In Y-Axis

SupplyDC

Power“Pick”Paper

ControlPrinter

CommandPrinter

Connectto

Host

CommunicatewithHost

DisplayStatus

AcceptUser

Inputs

Paper Tray PrintMechanism

Logic Board

Chassis

Enclosure

User Interface Board

Host DriverSoftware

Power Cordand “Brick”

Functionalor PhysicalElements

Chunks

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Geometric Layout

printmechanism

paper tray

user interface board

printcartridge

logicboard

chassis

chassis

paper

roller

print cartridge

paper tray

enclosure

logic board

height

The 3-D Schematic

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Incidental InteractionsEnclosure

Paper Tray

Chassis

PrintMechanism

User InterfaceBoard

LogicBoard

Power Cordand “Brick”

Host DriverSoftware

Styling

Vibration

Thermal Distortion

Thermal Distortion

RF InterferenceRF

Shielding

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Product Architecture Objectives

• Product architecture can be optimized to achieve certain economic objectives– Development Expense– Unit Cost– Product Performance– Development Schedule

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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

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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

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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

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Product Architecture --The End