1. Interface Design
Human Factors

2. Overview Interfaces of physical objects Human Factors
User-centered Design
Object Language
All contribute to ID concepts

3. General Ideas Making things easy (safe) to use
User error is impossible, or at least difficult
Object language: the “messages” designed into things
An important aspect is affordances

4. Affordances
Physical design features that afford some action—pushing, pressing, hooking the hand under, etc.
Also shaping things so that only fit correctly
Class: examples?

5. Affordances/Object Language
Environments: sidewalks, curbs, doorways
Soap dispensers in bathrooms
Door handles
Buttons, knobs, sliders—appliance controls
Remote controls

6. Psychology & Human Factors
People construct models of how things work
Models may not match reality
Examples: Chilly room, long traffic light
Good design should reduce superstition

7. Psychology (Mapping)
Mapping: if it isn’t obvious, users construct their own
Spatial (placement of controls)
Temporal (response follows an action)
Conceptual (the big picture)

8. Helping Users Know What to Do
Controls for different functions look different
Push/Pull doors, range controls
Norman’s nuclear tapper handles
Switches that do different things should tell what they do

9. Visibility & Feedback Make important parts & information visible
Progress bar for computer operation
Audio feedback—if it makes sense to user

10. Task Structure Organizing required decisions Think of menu systems
Wide and shallow: Baskin-Robbins
Narrow(er) and deep(er): Subway
Ideal: limit number of choices at each stage unfortunately, this doesn’t fit most tasks

11. General Conclusions
Acknowledge user’s view of the world and the task at hand
Make controls look like they do what they do
Group related functions
Make separate controls distinct

12. General Concusions Give visual cues about how things work
Give visual feedback that they are working
Use mappings from the user’s world
Avoid relying on written directions when possible

13. Caveat Some tasks don’t have natural mappings
They have cultural conventions (such as traffic signals)
Don’t violate these!