Design, prototyping and construction
1
The Task-Centered Design Process
figure out who's going to use the system to do what
choose representative tasks for task-centered design
plagiarize
rough out a design
think about it
create a mock-up or prototype
test it with users
iterate
build it
track it
change it
2
Overview
Prototyping and construction
Conceptual design
Physical design
Tool support
,3
Two guidelines for design
1. Provide a good conceptual model
allows user to predict the effects of our actions
problem:
designer’s conceptual model communicated to user through system image:
appearance, written instructions, system behaviour through interaction,
transfer, idioms and stereotypes
if system image does not make model clear and
consistent, user will develop wrong conceptual model
4
Two guidelines for design (continued)
2. Make things visible
relations between user’s intentions, required actions, and results are
sensible
non arbitrary
meaningful
,visible affordances, mappings, and constraints
use visible cultural idioms
reminds person of what can be done and how to do it
5
Prototyping and construction
What is a prototype?
Why prototype?
Different kinds of prototyping
low fidelity
high fidelity
Compromises in prototyping
vertical
horizontal
Construction
6
What is a prototype?
In other design fields a prototype is a small-scale model:
a miniature car
a miniature building or town
7
, What is a prototype?
In interaction design it can be (among other things):
a series of screen sketches
a storyboard, i.e. a cartoon-like series of scenes
a Powerpoint slide show
a video simulating the use of a system
a lump of wood (e.g. iphone)
a cardboard mock-up
a piece of software with limited functionality written in the target language or in another language
8
Why prototype?
Evaluation and feedback are central to interaction design
Stakeholders can see, hold, interact with a prototype more easily than a document or a drawing
Team members can communicate effectively
You can test out ideas for yourself
It encourages reflection: very important aspect of design
Prototypes answer questions, and support designers in choosing between alternatives
9
What to prototype?
Technical issues
1
The Task-Centered Design Process
figure out who's going to use the system to do what
choose representative tasks for task-centered design
plagiarize
rough out a design
think about it
create a mock-up or prototype
test it with users
iterate
build it
track it
change it
2
Overview
Prototyping and construction
Conceptual design
Physical design
Tool support
,3
Two guidelines for design
1. Provide a good conceptual model
allows user to predict the effects of our actions
problem:
designer’s conceptual model communicated to user through system image:
appearance, written instructions, system behaviour through interaction,
transfer, idioms and stereotypes
if system image does not make model clear and
consistent, user will develop wrong conceptual model
4
Two guidelines for design (continued)
2. Make things visible
relations between user’s intentions, required actions, and results are
sensible
non arbitrary
meaningful
,visible affordances, mappings, and constraints
use visible cultural idioms
reminds person of what can be done and how to do it
5
Prototyping and construction
What is a prototype?
Why prototype?
Different kinds of prototyping
low fidelity
high fidelity
Compromises in prototyping
vertical
horizontal
Construction
6
What is a prototype?
In other design fields a prototype is a small-scale model:
a miniature car
a miniature building or town
7
, What is a prototype?
In interaction design it can be (among other things):
a series of screen sketches
a storyboard, i.e. a cartoon-like series of scenes
a Powerpoint slide show
a video simulating the use of a system
a lump of wood (e.g. iphone)
a cardboard mock-up
a piece of software with limited functionality written in the target language or in another language
8
Why prototype?
Evaluation and feedback are central to interaction design
Stakeholders can see, hold, interact with a prototype more easily than a document or a drawing
Team members can communicate effectively
You can test out ideas for yourself
It encourages reflection: very important aspect of design
Prototypes answer questions, and support designers in choosing between alternatives
9
What to prototype?
Technical issues
