A fancy technological version of the "you're getting warmer, now you're getting colder" game is bringing GPS indoors:
Georgia Institute of Technology's … System for Wearable Audio Navigation, or SWAN, consists of a wearable computer connected to a headband packed with sensors that help sight-impaired users know where they are and how to get where they're going.
Besides a pendant-sized wireless GPS tracker, there are light sensors and thermometers that help distinguish between indoors and outdoors. Cameras gauge how far away objects and obstacles are. A compass establishes direction.
All the data are crunched by a computer in a backpack, which relays high-pitch sonarlike signals that direct users to their destinations.
The system is being developed for the blind, but might eventually be used by firefighters or soldiers faced with low visibility in unfamiliar situations.
Not all the kinks have been worked out of some of the older technology, though:
An 80-year-old German motorist has obediently followed his navigation system all the way into a huge pile of sand, abrubtly bringing his trip to an end.
Current GPS can only track with approximately a ten-foot radius, and can't see the difference between walls and open space indoors. And at the moment, the indoor tracking system has a highly specialized function, but so did GPS at first–now it's in everyone's cell phone. More fodder for discussing the convenience/privacy tradeoffs we're willing to make and the possible upsides of zero privacy.