Design Patterns

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

2. Design Patterns UbiComp Patterns Evaluations 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

3. Design Patterns UbiComp Patterns Evaluations 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.

4. Design Patterns UbiComp Patterns Evaluations 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)

5. Design Patterns UbiComp Patterns Evaluations 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

6. Design Patterns UbiComp Patterns Evaluations Chart of UbiComp Patterns

7. Design Patterns UbiComp Patterns Evaluations Chart of UbiComp Patterns

8. Design Patterns UbiComp Patterns Evaluations Applying Patterns • Exercise: Apply patterns to In/Out Board

9. Design Patterns UbiComp Patterns Evaluations 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

10. Design Patterns UbiComp Patterns Evaluations 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

11. Design Patterns UbiComp Patterns Evaluations 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

12. Thanks! Any questions or comments? http://kettle.cs.berkeley.edu/ubicomp

13. Design Patterns UbiComp Patterns Evaluations 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

14. Design Patterns UbiComp Patterns Evaluations 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

15. Design Patterns UbiComp Patterns Evaluations 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)