1 Design PatternsUbiComp PatternsEvaluations Design Patterns in Ubiquitous Computing Eric Chung Jason I. Hong Jimmy Lin James A. Landay.

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Design Patterns

UbiComp Patterns

Evaluations

Design Patterns in Ubiquitous Computing

Eric Chung

Jason I. Hong

Jimmy Lin

James A. Landay

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Introduction to Design Patterns

• Patterns are developed to communicate common problems and solutions for designers in a discipline

• First introduced by Christopher Alexander and his colleagues in the field of architecture

Design Patterns

UbiComp Patterns

Evaluations

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Beer Hall Example

• Problem:

– Where can peoplesing and drink, andshout and drink,and let go of their sorrows?

• Solution:

– Somewhere in the community at least one big place where a few hundred people can gather, with beer and wine, music, and perhaps a half-dozen activities, so that people are continuously crisscrossing from one to another.

Design Patterns

UbiComp Patterns

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Design Patterns for Ubiquitous Computing

• Help designers create higher-quality designs faster by developing a pattern language for UbiComp

• Difficult to identify patterns because many design issues are still active areas of research

• Difficult because certain problems do not have common solutions (have to resort to predictive patterns rather than descriptive)

Design Patterns

UbiComp Patterns

Evaluations

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Identifying Patterns• We developed a criteria for identifying patterns:

– Pattern should have at least one example in research and one example in industry

• A list of over 60 UbiComp patterns have been identified

• Patterns are grouped into several important UbiComp themes (e.g., privacy)

• A taxonomy of UbiComp applications is also important to consider

Design Patterns

UbiComp Patterns

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Chart of UbiComp Patterns

Design Patterns

UbiComp Patterns

Evaluations

Themes Infrastructure Privacy Identification Manageability Personalization

High-level Patterns

Proxies for devices

Service Handoff

Negotiation & Resolution

Relying on Multiple

Sources

Connections

Effective Deployment

Balance of Power

Building Trust and

Credibility

Social Situation

Purpose

Appropriate Scope

of Access

Scope of Control

Appropriate Scope

of Locality

Scope of Time

Partial Identification

User Identity

Anonymous

Pseudo-Identity

Bootstrap

Information Base

Ambiguity

Learning &Remembering Users

Medium-level Patterns

Privacy Zones

Data access via personalized devices

Choice

Access

Notice

Active/Smart Floor

Active Badge

Defaulting

Fault Detection

Bookmarks

Low-Level Patterns

AppropriateRetention Time

Global Positioning

RFID

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Chart of UbiComp Patterns

Design Patterns

UbiComp Patterns

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Appropriate Levels of Attention

Anticipation Global Data Discoverability Capture and Access

Physical Space Location-based Services

Natural Interfaces

Unobtrusive Prompting

Subtle Reminders

Context-Sensitive I/O

Active Teaching

Point of Action

Physical-Virtual Associations

Point of Information

Appropriate Rate of Update

Teleporting

Ambiguity

Learnability

Acceptance

Practices &Etiquettes

Experience Capture

Information Capture

Weiser’s Devices (inch, foot, yard)

Touring

Finding Locations

Tracking Users

Follow-me Display

Proximity-Based Tracking

World Model

Active Map

Proximity-Based Tracking

Wearable Computer

Accelerators

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Applying Patterns

• Exercise: Apply patterns to In/Out Board

Design Patterns

UbiComp Patterns

Evaluations

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Applying Patterns

• Exercise: Apply patterns to In/Out Board• Identify some relevant themes and their

patterns:– Privacy: Appropriate Scope of Locality, Partial

Identification (might only show first names), Choice, Access, Appropriate Retention Time

– Identification: Active Badge, Smart Floor– Global Data: Active Map

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UbiComp Patterns

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Evaluating the Patterns• Perform an experiment

– Conditions: create two groups, one with patterns, one without

– Task #1: ask the groups to evaluate an existing design

– Task #2: ask the groups to prototype a lo-fi UbiComp app

– Independent judges rate the quality of designs– Identify “shared language” used– Questionnaire on usefulness of patterns

Design Patterns

UbiComp Patterns

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Take-Away Ideas• Goal: identify design patterns for UbiComp in order

to help designers form higher-quality designs faster and to develop a “shared language”

• Design patterns for UbiComp are categorized at varying levels of abstraction underneath a set of main themes

• Design patterns should be evaluated rigorously

• The community is welcome to submit patterns to http://kettle.cs.berkeley.edu/ubicomp

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UbiComp Patterns

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Thanks!Any questions or comments?

http://kettle.cs.berkeley.edu/ubicomp

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What does a pattern look like?

• Design patterns typically range from 3-5 pages and provide general but descriptive methods for solving a particular problem

• A sensitizing image is useful for easy identification of the pattern

• Problems encountered may never be solved in an exact way and therefore design patterns are never too specific

• A Background suggests how the pattern is useful and how it can be combined with other patterns

• The Problem statement identifies a recurring problem in the discipline

• The Solution statement identifies the common solutions and provides details, suggestions, and tradeoffs

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Patterns in other Disciplines• In the mid-1990s, patterns became

popularized in other disciplines such as Software Engineering, Web Site Design, and UI Design.

– Design of Sites, Douglas K. van Duyne, James A. Landay, Jason I. Hong

– Design Patterns, Erich Gamma, Richard Helm, Ralph Johnson, John Vlissides

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UbiComp Genres

• Most UbiComp applications can be classified under the following application genres:

– Business (i.e. ParcTab)– Care and Maintenance (i.e. Context-Aware Clinics)– Collaboration (i.e. BlueBoard)– Education (i.e. Classroom 2000)– Emergency Response (i.e. Siren)– Fieldwork (i.e. FieldNote)– Guides (i.e. CyberGuide)– Laboratory (i.e. PlantCare)– Memory Aids (i.e. Personal Audio Loop)– Smart Homes (i.e. Georgia Tech’s Aware Home)– Smart Vehicles (i.e. Context-Aware GM)

Design Patterns

UbiComp Patterns

Evaluations