General Principles Of Human-computer-interaction

1. General Principles Of Human-computer-interaction

2. Outline • Foundations and theories of HCI • Understanding the User Experience • Design principles & guidelines • UX engineering processes • Conclusion

3. Foundations and theories of HCI • Relationship between human users and digital technology • Models: How does a user work, so we can predict how they interact with the UI? • Design new, effective ways for technologies of all purposes • Interaction techniques: • In 2D: standardized • In 3D: ??? • There is NO optimal design  tradeoffs

4. Understanding the User Experience

5. Long-Term Memory Understanding the User Experience Working Memory Cognitive Processor Human Processor Models Basic Idea Perceptual Processor Visual Image Store Auditory Image Store Motor Processor • Low-level atomic events, transfer & processing of data • Each processor has: • Estimated cycle time • Associated memory • Estimated capacity • Decay time •  Used to estimate human limitations

6. Understanding the User Experience Human Processor ModelKeystroke-Level Model • Easy to use • Task times can be predicted • Evaluation of designs prior development • Only measure time • Considers expert users • Considers error-free executions R – respond to motor operator, M – mentally prepare 1+ motor operator, H – home hands, K – perform motor skills, P –point to a target, D – draw a set of straight lines

7. Understanding the User Experience Human Processor ModelTouch-Level Model (TLM) Extensions of KLM to touchscreen and mobile devices,X – naturally occurring distraction, additional: tap, swipe, zoom….

8. Goal Understanding the User Experience Selection Human Processor ModelGOMS Method A Method B Operator A1 Operator B1 Operator A2 Operator B2 Operator A3 Goals: What does the user want to accomplish? Operators: all actions required to accomplish a goal Methods: specific sequences of actions Selection: method of choice, if more than one option For 3D UIs: still to be developed Human processor models have been used to design and analyze 3D interactions

9. Understanding the User Experience User Action ModelsBasic Idea High-level interactions between human and system • User’s goal • User’s execution of physical actions • Outcomes of those actions within the system • User’s evaluation of the outcome • Move object • Action plan: reach out and grab • System attaches object to movement of user’s hand • User sees that object moves

10. Understanding the User Experience User action modelSeven Stages Of Action (User-centric) Gulf Of Execution Goal Gulf Of Evaluation

11. Understanding the User Experience User action ModelUser Action Framework (USer-centric) Based on Seven Stages How to do it? Do it.

12. Understanding the User Experience User Action ModelUser-System Loop (system-centric) For 3D UIs!!! perceived by create manipulate Sends commands to alter updates

13. Understanding the User Experience Conceptual Models and Affordances • Conceptual models: understanding of the information and tasks that constitute a system • Designer’s model: how the designer understands the system • User’s model: how the user understands the system, based on experience • If designer model = user model  high level of usability • Affordance: • Increases the likelihood of user model = designer model • Cognitive, physical, functional & sensory 3D UIs: importance of physical affordance

14. Understanding the User Experience Activity Theory Interactions occur in real world, including other humans, systems, objects & activities “ecological perspective” of UX • Activity theory: • S (activity) O • Object-oriented • Subject: person/group in activity • Object: motive, that needs the meet of S • Activity system model: • Community as 3rd element Tool for analyzing user interactions in VR VR as tool to mediate the user’s ability to accomplish goal Tool for designing and evaluating 3D UIs

15. Understanding the User Experience Embodied Interaction • Tangible Computing: • Users interacting with digital information through the physical environment • Social Computing: • Any type of system that serves as a medium or focus for social relation Familiar real-world aspects computer systems interacting in our physical and social reality “the creation, manipulation, and sharing of meaning” – Dourish (2011) 3D UIs: Telepresence

16. Design Principles and guidelines

17. Design Principles and Guidelines Aspects • Goal-Oriented • Execution-Oriented • Outcome-Oriented • Evaluation-Oriented Four aspects from the User Action Model

18. Design Principles and Guidelines Goal-Oriented • Simplicity • Simple and task focused • Eliminate extraneous or redundant information (use filters) • Structure • Organized in a meaningful and useful way • Break down complex tasks into subtasks • Visibility • Self-explaining function of control • Employ familiar and recognizable visual icons and symbols

19. Design Principles and Guidelines Execution-Oriented • Affordance • Self-explanatory use of control • Leverage familiarity with common UIs • Direct manipulation • Consistency • Ergonomics • Clearance, Reach, Posture, Strength • Error Prevention • Permit only valid actions • Confirm irreversible actions • Offer common outcomes (autocomplete)

20. Design Principles and Guidelines Outcome-oriented • Automation • Offer common outcomes (autocomplete) • Avoid tedious interactions • Interaction methods to complete series of similar actions in parallel • Control • Too much automation  too little automation • Confirm feature for autocomplete • Provide features for novices & experts • Keep creativity of users in mind (avoid missing or incorrect functionality)

21. Design Principles and Guidelines Evaluation-Oriented • Feedback • Prominent for infrequent or major actions • Provide informative feedback (simple, comprehensible error messages) • Error Recovery • Help user to recognize, diagnose & recover from errors • Provide easy-to-reverse actions • Controls to reverse the outcome

22. Design Principles and Guidelines General Rules • Accessibility • For disabled persons (vision-, hearing, and/or mobility-impaired) • Vocabulary • Use vocabulary of intended user • Recognition • UI should provide knowledge required for operating the UI Recalling is much more difficult! • Let users know what their options are • Use pictures and visual representations

23. UxeNGINEeRING

24. Goal? UX Engineering Aspects • System Goals and Concepts • Requirements Analysis • The Design Process • Prototyping • Evaluating Prototypes Revisit previous activity

25. UX Engineering System Goals and Concepts • Improving Usability • Effectiveness, efficiency, satisfaction • Learnability, Retainability, Ease of Use, Speed of performance, Rate of errors, User comfort • Usefulness • System that provides functionality and serves a purpose • Emotional Impact •  especially powerful in 3D UIs

26. UX Engineering Requirements Analysis • Inquire & analyze the context • Extract the requirements • Functional (what?) • Performance (how?) • Interface (which characteristics?)

27. UX Engineering The Design Process • Design Tools • Ideation, Sketching, Critiquing • Design Perspectives • Interaction, ecological, emotional • Design Approaches • Activity, Information, Interaction • Design Representations • Metaphors, design scenarios, storyboards, physical mockups

28. UX Engineering Prototyping • Communicate planned functionality and design • Number & functionality of features  different combos  different prototypes • Level of fidelity • Level of interactivity

29. UX Engineering Evaluating Prototypes Formative(during the process) Rapid(cognitive walkthroughs & heuristic methods) Analytic(analyzing inherent attributes of design) Summative (during final iteration) Rigorous (formal, systematic methods) Empirical(observing users) vs.

30. Conclusion What we learned: • Models to understand the user • Designs and guidelines to make user-friendly UIs • Engineering the UX Applied to 3D UIs:  most 2D UI models applicable to 3D UIs, still research potential  no standardized way of doing things  more focus on emotional and physical impact  Iterative process, also for 3D UIs