constraints

knowing what to do

types of constraints

physical

cultural

semantic

logical

physical

physical limitations

constrain possible operations through physical properties

best when restricting before interaction

orientation

directional movement

advantages of physical constraints

rely upon properties of physical world

no special training

encourage desired actions by limiting others

cultural

cultural constraints

cultural norms: allowable actions for social situations

shared by a group

learned

not universal, change with time

can make errors

twitch chat

what do you do when using something new?

youtube tutorials

mac help menu

semantic

semantic constraints

rely upon meaning of the situation

rely upon knowledge of the world

learned, not universal

logical

logical constraints

reasonable understanding of how something works

trial and error

conventions and standards

conventions

cultural constraints

inform how people should behave in (social) interactions

conflicts disrupt interaction

chat interfaces

coding conventions

changes in conventions

difficult to change

users object and complain

requires new learning

benefits need to outweigh costs

windows 7 start menu

windows 8 start menu

windows 10 start menu

experiences with changes?

constraints and forcing behavior

forcing functions

form of physical constraint

failure at one stage prevents next steps

strong constraint to prevent behaviors

lock-ins

keep an operation active

prevent prematurely stopping

dialog boxes

modal toolbars

lockouts

prevent an event from occurring

used for safety reasons

can be nuisance

minimize nuisance, maintain safety

interlocks

force the proper sequence

questions?

reading for next class

Chapter 2: Process of Interaction Design
Interaction Design

 

Chapter 6:
Design Thinking
The Design of Everyday Things