Disorienteering

[bnewman]

Something I read recently reminded me of this idea I once had.

Orienteering is the sport of navigating with a map and compass. I've done some orienteering activities at camps, it's fun — of course, competitive orienteering requires that you be a good navigator and a fast runner/biker/etc., and I'm only the former.

The basic idea of navigating with a map and compass is that you can use the compass to orient the map to the terrain. This works because the Earth's magnetic field is approximately uniform over a small area. However, the Earth's isn't the only magnetic field! "Disorienteering" is the (so far imaginary) sport of navigating with a map and compass through an obstacle course of strong, local magnetic anomalies. Puzzles involved in a disorienteering course might include instructions to turn electromagnets on or off to alter the course, instructions to travel in the straight line indicated by a bearing or to follow a (curved) magnetic field line, unmarked reference points located at the intersection of two path segments, etc.

One thing I'm curious about is how much hardware you'd need to set up a disorienteering course. The Earth's magnetic field isn't all that strong, but to create a magnetic obstacle course big enough for a person to get lost in (if you can't get physically lost in it, might as well just call it a board game...) might call for a lot of electromagnets...

Comments

[orawnzva.livejournal.com]

I've gotten kudos for my ability to orient myself to a USGS topo map by looking at the terrain, a feat which I credit to the clarity of the maps.

[tamias.livejournal.com]

You should also get kudos for doing it that way because that is, in fact, The Right Way--it's too easy to lie to yourself about where you are if you start from the map.

There's a nominal version of disorienteering that happens when you're a pilot studying for (or flying using) an instrument rating. Then you do all kinds of crazy radio navigation, which includes significant issues about signal clarity, scalloping, etc., and also sometimes has you tracking bearings, sometimes homing on a transmitter, and sometimes tracking arcs a specified distance from a transmitting point.

Come to think of it, disorienteering in airplanes is even more exciting because you're in three dimensions and have to coordinate the fact that you're always injecting positional uncertainty through the differences in wind (x and y axes) and temperature/pressure (z axis).

That said, you really can't just turn radio transmitters on and off. So maybe the aviation version of disorienteering would be to have a GPS running in the plane, with the display turned on, set to track. Then you fly the various instructions, which are sent to you by radio at present points. At the end, you look at your ground track, and the person whose ground track most closely matches the Platonic ideal is the winner.