(Or, Where Have All The Rude Boys Gone?)
A while back (FIXME: Need a link!) there was an Amateur Scientist column in Scientific American that asked for ideas on making a floater: a probe that would be dropped into the ocean, be directed by ocean currents, and periodically report back on its position. This fascinated me; it fit in with an idea I'd had since I was a teenager about a self-directed aquatic robot that could find its way to oceans. (Think Paddle-to-the-Sea combined with Spirit/Opportunity.)
This page is here to keep me from losing my notes every few months when I come across another useful link. With any luck, someone else might think this is neat as well.
~ObLink: Very much inspired by this page. You haven't been?
Drop it in the Pacific Ocean. Let it float around. Most of the time the Gumstix/GPS/whatever else will be off. Periodically the thing will wake up, take GPS readings, and radio them home. Figure on a lifespan of at least a month, but aim for six months.
(Or, If my kernel's compiling, don't come a-knockin.)
Could it not run Linux? Best not even to consider it.
The Gumstix computer looks like my best bet: 200mA of current (better than the Soekris boards), 3.5-5.0V, and 200-400 MHz (!). Two serial and one USB port...we're set.
(Or, you should see my lovely cupcakes.)
I think I can get away with the iSun combined with the GumstixFloater. Total cost: about $120 Cdn, and that's at Crappy Tire. Aw yeah. iSun: 290 mA @7.6V. Can be daisy-chained. [One comment suggests that combining the iSun and the BattPakk with a sufficient number of batteries may allow continuous power...sweet.
Another option may be funky solar lights I've seen recently at Home Depot: they charge an AA battery with a solar cell, which turns on at night to power a tiny li'l LED that looks cute in your front lawn. No, I really don't know what I'm doing here.
A little bigger, but: http://www.qkits.com/serv/qkits/kin/pages/10009.asp
Smaller, cheaper, less ruggedized: http://www.action2k.com/solar.htm
(Or, many, many concepts I don't understand yet.)
It'll have to be amateur radio, since with luck I'm hoping that the floater will get out into, like, The Real Ocean and everything. Packet radio could work; store-and-forward messages may be best suited, especially if we limit messages to just GPS data rather than JPGs of waves.
The Gumstix may need to figure out when a satellite will be overhead, and turn itself on then. How to time this?
Based on this comment, the Motorola ~OnCore GPS boards look pretty promising. Ebay seems to have them for $25-$50 Canadian, which is quite reasonable.
According to the specs, it takes around 90 seconds from a cold start to get position. Power could be interesting: 5V, 155mA "without antenna". Anyone care to clarify what that means? Still, that's only a couple of iSuns (including the Gumstix)...
(Or, my memory isn't what it...huh?)