Case Study
Consumer Devices
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Introduction
• 3D Input Device
• Video Recording Devices
• Mobile Communications
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3D Input Devices
• Multiple degrees of freedom
– Most devices give you 2 degrees
– Usable, but non-natural for 3D applications
– We want control of Z axis, and 3 axes of
rotation
• Several different input devices allow this
– Data Glove
– Spaceball
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History of the Spaceball
• Company founded in the late 1980s,
Spaceball Technologies
• Later renamed Spacetec IMC (Interactive
Motion Control)
• Later absorbed by Logitech, then spun off
as 3DConnexions
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How Does It Work?
• Internal sensors detect displacements / torques
along 3 different axes
• Firmware converts into a sream of data, sent to
the computer via serial interface
• Data forwarded to "Spaceball aware"
applications, which usually convert it into 3D
translation / rotation vectors and move
something in 3D visual space
• Mappable function keys provide applicationspecific shortcuts
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Applications
• Mainly industrial CAD designers
(automotive, aerospace)
• Creative applications (3D Studio MAX)
• PC Gaming
– Hand-held version: SpaceOrb
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How Well Does It Work?
• Very well for CAD / creative apps
– Natural mapping to the 3D world
– Function keys facilitate bimanual input
• Less well for games, but very subjective
• Not great as a 2D pointing device
– Slightly less effective than a joystick
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Video Recording Devices
• As televisions have fairly ubiquitous, time
to watch what is shown has often grown
less
– 200 channels and nothing is on!
• Starting in the 80s, a TV "peripheral" was
introduced to solve these problems
• Video Cassette Recorder (VCR)
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Use Model of the Device
• Goal: Record and playback of video
• Task: Record video signals
– Subtask: Allow scheduling of recordings
• Task: Playback
– Subtask: Searching of recorded "data"
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Artifacts of the Model
• Video Cassette: magnetic recordable
media
• Fast Forward and Reverse
– Media only supports linear searching
• Start and End of recording times
– Lack of updatable data model required end
users to retain lots of domain knowledge to
correctly schedule
– No error trapping
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Who Cares About Cassettes?
• The name is now also ubiquitous, but
describes the relationship to the media
• What if we recorded onto CD? DVD?
Hard disk?
– Next generation: Digital Video Recorder
(DVR)
• ReplayTV
• DirectTV
• TiVo (  Jeff says, Best toy EVER!)
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Same Tasks, New Artifacts
• Digital media, and integration of (also
ubiquitous) computing technology allows for
a whole new interface
• Scheduling of recordings
– Start and end times
– Updatable database allows reduction of
cognitive load:
• Schedule by name ("Record Enterprise") instead of
time
• Automatic scheduling ("Record *all* episodes")
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Same Tasks, New Artifacts
• Searching
– Fast forward and reverse
– Digital format allows variable speeds
– Non-linear traversal (jump to end of recording)
• Output to “hard” media
– Dump to VCR
– Burn DVD
– Email!
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Interaction
• User input accomplished using special
purpose remote keypad
– Up/down/left/right and enter keys
– Essentially menu selection and limited form
fillin
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Task: Schedule Recording
• Support recording by selecting times
• Select programs by name
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Task: Playback
• Select program to playback
• Improved searching
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Digital Video Improvements
• TiVo performs all the same tasks as its
ancestor, and:
– Reduces errors / memory load
– Allows improved searching
• Interface appears acceptable to users
– Familiar (VCR) style
– Menu traversal
– Virtual keyboard
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Mobile Communication
• Most common: mobile voice (cell phones)
• Also
– Email
– IM
– Web browsing
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Cell Phones
• Task: Call someone
– Subtask: enter the number to dial
• Task: Answer incoming call
• Artifacts: phone
• This is all the early phones had, but new
technologies have allowed more features to
reduce cognitive load
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Task: Call someone
• Simple task, but lots of conditions
– Nature of mobile device means we needs to
know if it's possible to make a call (signal
strength)
• Artifact: signal meter
– Household phones have supported speed-dial
for years, users expect it
• Artifact: method to setup speed dialing
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Task: Call someone
• Computing technology allows us to store
and numbers, reducing the cognitive load
– Artifacts:
• setup / retrieve numbers
• capture caller ID numbers
• capture outgoing calls
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Task: Answer incoming calls
• Simple task, different conditions
– Cell phones often used while driving. We want
to reduce potential errors....
• Artifact: hands free capability
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Additional 'Tasks'
• Cell phone manufacturers are rushing to combine
many other 'tasks' into their phone designs
– Buy one device, not several
– Pros: eliminates additional devices, plays to Geek
Factor
– Cons: single point of failure, conflicting modalities
• Not a bad thing as long as the primary tasks
aren't compromised
– Early Palm Pilot phones were had a form factor that
made it cumbersome as an actual phone
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Product: Sanyo Flip-phone
• Task: call someone
– Enter numbers directly
– Enter/retrieve numbers from phone book
• Shortcut key to phonebook (reduce load, errors)
– Speed dial
– Voice dial
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Product: Sanyo Flip-phone
• Task: answer incoming call
– One-touch answer
– Hands free (requires external device)
– Caller ID
• Special rings/graphics per caller, so can easily
decide to answer or not
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Product: Sanyo Flip-phone
• Additional tasks:
– Voicemail (users require it)
– Web browser
• Downloadable content (apps, ringers)
– Text messaging
– Camera
• Note: sound of picture being taken can’t be
silenced. Why?
– Calculator
– Calendar
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Product: Sanyo Flip-phone
• Additional task support:
– Menu selection, with shortcuts
• Menu has a ‘Back’ option to repair errors
– Early Nokia phones did not have this
– Alphabetic entry via cell number keys
• Awkward, but users accept it
• Palm Pilot phone does better, but sacrifices form
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