Autonomous Catamaran


[Gabriel] put together an impressive writeup of his autonomous catamaran, Atlantis(PDF). It was certainly done as an academic project, but there’s a thorough explanation of the math logic behind the control systems. The heart of the boat was a waterproofed Pentium laptop with a CAN bus parallel interface used to talk to everything on-board. Sensors included GPS, wind, hull speed and rudder angle. In case the site can’t handle the load, I’ve mirrored the 1.4MB PDF here.

Underwater GPS (sorta)


Since water blocks the radio frequency used for GPS triangulation, GPS is considered pretty useless for SCUBA divers. Apparenlty some of them are finding it useful to waterproof off the shelf units for tracking the beginning and end of dives. (Dives in open water often involve currents that can really move you along.) To avoid any wiring, a floating case is used. When the diver wants to grab a waypoint, he/she lets the gps surface for a short while to acquire a fix. Then the diver can pull it back down and mark the waypoint or record the coordinates.

D200 Hotshoe GPS Redux (el Cheapo Version)


It’s been a while since we talked about putting a GPS on top of a D200. [Rick] sent in his latest version. He used a nice 20 channel sirf III gps from spark-fun, a cheap D200 remote cable and a few parts to send the NMEA sentences down the wire. The biggest improvements include taking the $100 Nikon cable out of the mix and swiping power from the camera for the GPS board. All the info is there, but I had to seriously stare at his wiring instructions for a while despite the low parts count. I like to see actual circuit diagrams!

Hack-upgrade Your Magellan GPS


[dgoeken] sent in his Magellan 3100 hack. The device runs Windows CE 5.0, and mounts as a standard flash drive. Since everything is easily accessible, it’s just a matter of replacing and modifying the appropriate files. According to the GpsPassion message board, some are finding his guide useful for other models of Magellan GPS. So far he’s added a file manager, media player and upgraded the Points of Interest file. The site is slightly bandwidth challenged, so I’ve mirrored his hack process here.

Build Your Own GPS And GLONASS Receiver

[superlopez] sent in this detailed article (mirrored here and here) which describes how to build a GPS and GLONASS (the Russian version of GPS) receiver. The resulting device is gigantic compared to one of those tiny bluetooth USB GPS units, but the ability to build one’s own receiver is one of those post-apocalyptic skills I sure would like to have. The creator of the article [Matjaz Vidmar] aka [S53MV] also has pages on Packet-Radio (PKT) transceiver improvements (PKT gets my vote for the best post-apocalyptic technology, and the only believable technology featured in the Transformers movie), and a more sophisticated homemade frequency counter than the one featured earlier this summer.

In 2005 we featured a from-scratch GPS receiver as well, thought the project site seems to be down. If your GPS unit just needs a better antenna, check out [Will]’s how-to from last year.

Simple GPS Data Logger


[Stefan] sent in this data logger that was built for a weather balloon project. It’s a very clean design that logs to a 64KB eeprom, can transmit its location via SMS through a cell phone and trigger a camera based on position if needed. The site has a tarball will full schematics and source – mod away.