28-05-2014, 12:54 PM
Ubiquitous and Mobile Computing new directions in user system interaction
Ubiquitous Computing
• Two issues are of crucial importance:
location and scale
• Location : ubiquitous computers must know where they are
• Inch-scale machines: approximate active Post-It notes
• Foot-scale machines: like a sheet of paper (or a book or a magazine)
• Yard-scale machines: the equivalent of a blackboard or bulletin board
• Prototype tabs, pads and boards are just the
beginning of ubiquitous computing
The PARCtab
• The PARCtab is most easily
operated with two hands: one to
hold the tab, the other to use a
passive stylus or a finger to touch
the screen.
• But since office workers often
seem to have their hands full, we
designed the tab so that three
mechanical buttons fall beneath the
fingers of the same hand that holds
the tab, allowing one-handed use.
• The device also includes a piezo-
electric speaker so that applications
can generate audio feedback
The PARCTAB transceiver
Xerox PARC designed the transceiver
conservatively to ensure reliable
communication. For transmission, two
dozen IR emitters are placed at 15
degree intervals on a circular printed
circuit board. For reception, two
detectors provide a total viewing angle
of 360 degrees. The transceiver is
designed to be attached to a ceiling,
preferably in the middle of a room as
this usually gives an unobscured
communication path over the required
area.
Wearable Computer
• Providing hands-free operation
• Sharing the data in real-time with
background
• Supporting user comfort
• Allowing audio interactions in a
noisy environment
• Creating a simple user interface
• Keeping costs down