Basic Principles of NUI Design
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Design for Fingers, not Cursors
Touch targets need to be much larger than for desktop: 8-10mm for tips, 10-14mm for finger pads.
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Remember physiology and kinesiology
Don’t make users do overextensions or repetitive tasks.
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No gorilla arm
Humans weren’t meant to do many tasks with hands up in front of their bodies for long periods of time. Sorry Minority Report.
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Screen coverage
Fingers are attached to a palm, which can cover the screen while you are trying to do a gesture. Avoid putting essential elements like labels below a control, as it can be obscured by the user’s own hand. Place items like menus at the bottom of the screen to avoid this phenomenon.
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Know the technology
The kind of touchscreen, sensor or camera determines the kind of gestures you can design for.
The more challenging the gesture, the fewer people who will be able to (or want to) perform it. -
Trigger actions on release, not on press
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Attraction affordance
Use a simple gesture to get users to start using the system.
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Avoid unintentional triggers
A variety of everyday movements on the user’s part can accidentally trigger the system. Avoid.
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Gestures and Command Keys
Provide an easy (buttons, sliders, menu items, etc.) ways to access functionality, but provide advanced, learnable gestures as shortcuts.
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Requisite variety
There’s a wide range of ways to perform any gesture. Account for that.
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Match the complexity of the gesture to the complexity and frequency of the task
Simple, frequently used tasks should have equally simple gestures to trigger them.