GPS: The Art of Staying Found

October 2003

It's easy to forget the arbitrary nature of time--all these hours and minutes being an invention of the human mind. Nature offers only the rolling of this planet and its free fall around the sun. We make up the rest.

To whom do we owe this division of our days into the hours and minutes that so frantically race through our lives? The Medieval monks. They invented the mechanical clock so they would know when to say their prayers.

And now our lives are ruled by these divisions. At any moment we can precisely locate ourselves in the expanse of time.

I thought about this the first time I read about the new Global Positioning System back in 1983. We had perfectly segmented time, and now we had a way to perfectly segment space--to always know precisely our location on this Earth.

You must have heard of GPS. You can now buy a small device for less than $100 that receives a signal from three or more satellites, telling you exactly where you on Earth are. (It was men who needed this, of course, because of their unwillingness to ask directions.)

First developed for the military, GPS was soon made available to ordinary Joes and Jills. But for a number of years, the government disallowed GPS from being very accurate, thinking that any GI Joe or Jill from another country could use it to very accurately target us with missiles or the like.

But then they changed their mind--no doubt out of concern for the ordinary Joes who hated asking for directions. Today's GPS devices on the market can tell you your longitude and latitude within 10 feet.

So what good is knowing your longitude and latitude? Frankly, it wouldn't mean much to me. But it means a lot to the little gizmo in my hand. As GPS has developed, so have mobile devices, which now have a huge amount of computing power.

Simply put, companies have dumped a lot of map data into these devices, such that your handheld device takes that information and tells you that you're located at 1000 N Main Street.

One of the major uses is navigation: while you're driving your car the device shows on a map where you're located and can give you directions for wherever you want to go. Some devices even use voice synthesis: "In one minute turn left on Lombard Avenue."

Hikers, hunters, fisherman, and others also use GPS to find their way around the wilderness. One neat feature is the ability to store locations or "waypoints." Today's devices can typically store up to 500. Say you're a fisherman and you've found a hot spot--an exact location that you're eager to return to. Store it as a waypoint, and the crumbs will always lead you back. (That's a reference to the tale of Hansel and Gretel, in case you're wondering.)

In addition to maps, GPS is increasingly being used in conjunction with city guides. Let's say you're on a street corner in Chicago and have a hankering for Chinese food. Your GPS-enabled device senses your location and tells you how to get to the nearest Chinese restaurant.

It was just a little over three years ago that the government lifted the restrictions on accuracy, and since then GPS applications have continued to soar. And like everything else electronic, volume reduces price, such that GPS will likely soon be ubiquitous--in every auto and cell phone, for example.

A colleague has GPS capability on her Pocket PC and even occasionally uses it on an airplane to see how fast the plane is traveling and to track its progress toward her destination. Another colleague has an electronic motorbike that uses GPS for the speedometer.

GPS is fun, too. There's even a new sport of "geocaching": hiding little treasures and then posting their coordinates on the geocaching website (www.geocaching.com) so that people can use GPS to find them. How popular is this sport? There are no fewer than 67 caches hidden within 50 miles of Fairfield. The game typically works like this: you use your device to find the cache, open it, remove an item and replace it with something else, and then hide the cache for someone else to find.

What else is fun about GPS? I read about a company that sells software that combines GPS with the Internet, thereby making it possible to have web sites that are only visible, say, on a particular park bench.

The possibilities are endless--and it's all coming soon to a device near you.

You can find a good intro to GPS devices at http://gpsinformation.net. Also, there's an excellent intro on how GPS works at www.howstuffworks.com. A sample navigator/city guide product can be found at www.mapopolis.com.

© 2003 by Jim Karpen, Ph.D.

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