Introduction to User Centred Design
- 1. Introduction to User Centred Design Szonya Durant, Nuno Barreiro, Carlos Matos Lecture 1 PC3001, PC4001, PC5001, CS2847
- 2. Introduction to User Centred Design Szonya Durant, Nuno Barreiro, Carlos Matos
- 3. Introduction to User Centred Design Szonya Durant, Nuno Barreiro, Carlos Matos
- 4. A multidisciplinary subject The ‘user’ – Psychology Design – Computer Science and Media Arts Need to design ‘with the mind in mind’ Technology works in certain ways – so do users What is displayed does not necessarilydictate what is perceived 4
- 5. Aims Understand what user centred design is, its principles and challenges Build prototypes using different media and technologies - keeping the user in mind Evaluate the usability and suitability of user interfaces Understand testing (with users) as means of evaluating and improving usability 5
- 6. The user: Psychological human factors “Above the neck factors” Sometimes referred to as ‘cognitive ergonomics’ or ‘cognitive engineering’ Applications of principles of behaviour and cognition beyond the laboratory in industry, schools, medicine and sports. 6
- 7. To err is human Accident reports • aircrash, industrial accident, hospital mistake • enquiry blames ‘human error’ but • concrete lintel breaks due to weight • blame ‘lintel error’? It's a design error (we know how concrete behaves under stress) Human ‘error’ is normal • we know how users behave under stress • we should design for it 7
- 8. The user: human information processing Wickens et al. Pp. 4 Sensory processing Perception Working memory Response selection Response execution System Environment (Feedback) Long-term memory Attention resources Selection 8
- 9. The user: modulatory factors Individual differences - age, background, different abilities, different attitudes Stress/fatigue Organizational/societalfactors Expertise 9
- 10. Know your users Who are they? Talk to them Watch them Measure them Use your imagination to establish example users Read the literature... 10
- 11. Persona Description of an ‘example’ user not necessarilya real person Use as surrogateuser “What would Betty think?” Details matter makes her ‘real’ Do your research: “average” behaviour can be useful, But stereotypes can also be dangerous! 11
- 12. What is design? "A design is a plan or specification for the construction of an object or system or for the implementation of an activity or process, or the result of that plan or specification in the form of a prototype, product or process." Wikipedia 12
- 13. What is interaction? • Communication between a user and a system • Two-way communication • Several stages 13
- 14. Interaction design Achieving goals within constraints • Goals (purpose) who is it for, why do they want it • Constraints materials,platforms, cost, safety • Trade-offs functionality/simplicity, quality/cost 14
- 15. • Ergonomic minimum button size • Physical high-voltage switches are big • Legal and safety high cooker controls • Context and environment easy to clean • Aesthetic must look good • Economic cost of production is always a concern Constraints 15
- 16. Understand your materials In the case of designing for working with computers • Understand computers limitations,capacities,tools, platforms • Understand people psychology, sociology, human error • Understand their interaction how, when, why, etc. 16
- 17. Paradigm shifts Batch processing Timesharing Networking Graphical display Microprocessor WWW Ubiquitous computing (Internet of Things) 1950s 1960s 1970s 1980s 1980s 1990s New paradigms bring new kinds of interaction 17
- 18. Traditional interaction styles Commandline interface (CLI) Menus WIMP Point and click Suitable for repetitive tasks Better for expert users than novices Set of optionsdisplayed on the screen Less recall, but names should be meaningful Windows, Icons, Menus, Pointers Default style for most desktops and laptops Multimedia, Web browsers, hypertext Click on icons, text links, location on map 18
- 19. Other interaction styles Familiar to user Speech recognition or typed Suited for novices but restricted functionality Often used in information systems Primarily for data entry or data retrieval Require validation/correction facilities VR (virtual reality) 3D workspaces Natural language Question/answerinterfaces Form-fills Three-dimensional interfaces 19
- 20. Interaction styles and controllers • Menus, forms, command line and direct manipulation • Touchscreens • Control by speech • Game console controllers • Controlling with gestures • Locomotion in space 20
- 21. Donald Norman’s model Forming the goal Forming the intention Specifying the action Executing the action Observer Evaluating the outcome Interpreting the state of the world Perceiving the state of the world System EXECUTION EVALUATION 1. What do I want to accomplish? 2. What are the alternative actionsequences? 3. What action can I do now? 4. How do I do it? 5. What happened? 6. What does this mean? 7. Have I accomplished my goal? FEEDFORWARD FEEDBACK 21
- 22. Design process What is wanted Analysis Design Implement and deploy Evaluation heuristics Prototype Interviews; Ethnography; Surveys Architectures; Documentation; Help Scenarios; Task analysis Guidelines; Principles Dialogue notations Precise specification Build 22
- 23. Requirements Trade-offs Safety (front panel of a cooker is safer for adults, the rear panel is safer for children) Ergonomics vs physical (multifunction controls or reduced functionality) Fluidity (physical aspects vs logical effect) Is the logical state revealed in the physical state? (on/off buttons) Do inverse actions inverse effects? (arrow buttons, twist controls) 23
- 24. Scenarios Stories for design what will users want to do? Step-by-step walkthrough what can they see (sketches,screen shots) what do they do (keyboard, mouse etc.) what are they thinking? Use and reuse throughout design 24
- 25. Use scenarios to… Communicate with others designers,clients, users Validate other models ‘play’ it against other models Express dynamics screenshots– appearance scenario – behaviour 25
- 26. Scenarios are linear A scenariois one linear path through the system • Pros life and time are linear easy to understand(storiesand narrative are natural) concrete (errorsare less likely) • Cons no choice,no branches,no special conditions missthe unintended • So… use several scenarios use several methods compilescenariosinto user journeys 26
- 27. A user should always know • Where they are • What they can do • Where they are going or what will happen next • Where they have been or what they’ve done 27
- 28. Teaching on this course • Interdisciplinary teaching team • Lectures provide overall information structure • Workshopsalso contain essential information as well as a structuredway of working on the project (hands-on way of learning) • Group project work in interdisciplinary teams (transferable skills) • Move beyond screen-based design to cutting edge consideration on virtual environments 28
- 29. Project work and assessment • Individual lab quizzes – 10% 5 quizzes, 4 best grades • Group project interim submission - 20% task analysis and storyboard • Individual peer evaluation - 10% prototypeevaluation • Group project final submission - 20% low-fi prototype • Individual final report - 40% reflection on the project work 29