Hardware Reference
In-Depth Information
Refining doesn't have to mean getting a more accurate
physical position. Sometimes you refine what you know
about the context or activity, not the position. When you
have a rough idea of where something's happening, you
need to know about the activity at that location in order to
provide a response. In the interactive installation example,
you may never need to know the viewer's physical coor-
dinates in feet and inches (or meters and centimeters).
When you know which object he's close to in the room—
and whether he's close enough to relate to it—you can
make that object respond. You might be changing the
graphics on a display when he walks near, or activating an
animatronic sculpture as he walks by. In both cases, you
don't need to know the precise distance; you just need
to know he's close enough to pay attention. Sometimes
distance-ranging sensors are used as motion detectors
to define general zones of activity rather than to measure
distance.
35 Ways to Find
Your Location
At the 2004 O'Reilly Emerging Technology Confer-
ence (ETech), interaction designer and writer Chris
Heathcote gave an excellent presentation on cultural
and technological solutions to finding things, entitled
35 Ways to Find Your Location
. He outlined a number of
important factors to keep in mind before you choose
tools to do the job. He pointed out that the best way to
locate someone or something involves a combination
of technological methods and interpretation of cultural
and behavioral cues. His list is a handy tool for inspiring
solutions when you need to develop a system to find
locations. A few of the more popular techniques that
Chris listed are:
Determining proximity doesn't always give you enough
information to take action. Refining can also involve deter-
mining the orientation of one object relative to another.
For example, if you're giving directions, you need to know
which way you're oriented. It's also valuable information
when two people or objects are close to each other. You
don't want to activate the animatronic sculpture if the
viewer has his back to the thing!
X
• Assume: the Earth. Or a smaller domain, but assume
that's the largest space you have to look in.
• Use the time.
• Ask someone.
• Association: who or what are you near?
• Proximity to phone boxes, public transport stops,
and utility markings.
• Use a map.
• Which cell phone operators are available?
• Public phone operators?
• Phone number syntax?
• Newspapers available?
• Language being spoken?
• Post codes/ZIP codes.
• Street names.
• Street corners/intersections.
• Street numbers.
• Business names.
• Mobile phone location, through triangulation or
trilateration.
• Triangulation and trilateration on other radio
infrastructures, such as TV, radio, and public WiFi.
• GPS, assisted GPS, WAAS, and other GPS
enhancements.
• Landmarks and “littlemarks.”
• Dead reckoning.
