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Introduction toDesign Principles
Based on Don Norman’s book“The Design of Everyday Things”
Michael Rawlins, Director, Interaction Design & Strategy
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Why me?• I’m very curious…• I understand multiple disciplines.• Bad user experiences bother me.• I have passion for solving problems.• I’m intrigued by how different we
all are as people…Michael Rawlins
Interaction Designer
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About Don Norman• A cognitive scientist and engineer who pioneered concepts
related to user centered design.• Worked at Apple & HP. Now @ NNG (http://www.nngroup.com)
• Examines everyday things as examples of problematicdesigns.
• Established Design Principles as a framework fordiscussing and thinking about interaction problems.
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Design Principles• Visibility - can I see the interaction?• Feedback - what’s the object or device doing right now?• Affordance - how do I use it?• Mapping - where am I & where can I go?• Constraints - why can’t I do that?• Consistency - is this familiar?
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Visibility• Can you see the state of the device
& possible actions?• Are the controls positioned in a
manner where they can easily befound and used?
• Problems arise when users can’t seehow to use the device.
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Poor Visibility• Which controls are ambiguous?• How does this device turn off?• Which controls have meanings that
are unclear?.
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Better Visibility
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Feedback• What is the device doing right now?• What action is being performed?
Feedback is often multi-sensory
(an audible click and a visual clue of interaction)
How does this work?
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Affordance• Perceived and actual properties of an object that provides
clues to its operation.
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Poor Affordance?• What’s clickable below?
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Better Affordance…• Why do these examples have
better visual affordance?
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Mapping• The relationship between controls and
their effect.• Do these devices work with each
other?
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Mapping• Problematic examples (what’s good and what’s bad?)
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Constraints• Restricting the kind of actions a user
can take.
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Constraints• How is the users attention
directed to notice thesystem constraints?
• What other constraintsshould the user notice?
• How does users safetyimpact the design of thisgas pump?
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Consistency• Design interfaces to have
similar operations & usesimilar elements for achievinglike tasks.
• Similarity increaseslearnability.
• Design to aid prior systemknowledge - and aid the usersshort and long-term memory.
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ConsistencyFour types of consistency:• Aesthetic - style & appearance is repeated to enhance
recognition.• Functional - meaning and action is consistent to reinforce
learnability and understanding.• Internal - indicates a system is planned & well thought out
(cultivates trust and user orientation).• External - establishing an ecosystem & consistency with
other elements in the environment.
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Conclusion…Design Principles are validated by usability methods:• Learnability - how easy is it to perform basic tasks upon the
users first encounter with the device or interface.• Efficiency - once the users are familiar with the interface, how
quickly and effectively can they perform tasks.• Memorability - when users return after not having used the
system, how quickly can they reestablish proficiency?• Errors - how many errors do users make? How severe are the
errors? Can the users easily recover from errors?• Satisfaction - how pleasant and effective is the user experience?
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Further Reading…
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Thank You…
Credit to David Gelb