Mikel Maron’s fireside-style talk at the Sussex Geek Dinner was a great introduction to OpenStreetMap: “providing free geographic data such as street maps to anyone who wants them”. If you need to know anything about this area, Mikel is clearly the person to talk to.

Jane’s blogged about the talk, so I’ll skip that and just mention that the talk inspired me to take another look at the Bluetooth GPS unit we have. Turns out it’s easy to get the GPS unit running with a MacBook via the terminal: pair with the device, and then in Bluetooth Preferences, select the device and check the serial ports. In my case, I didn’t have to do anything, as the Mac had already set it up as a serial device. From the shell, you can then connect to the device…

$ screen /dev/tty.BT-GPS-3404F4-BT-GPSCOM-1

…and it starts spewing data:

$GPGSA,A,3,20,01,11,17,,,,,,,,,2.6,2.4,1.0*34
$GPRMC,164654.000,A,5049.4955,N,00008.8944,W,0.06,87.03,180107,,*2C
$GPGGA,164655.000,5049.4957,N,00008.8945,W,1,04,2.4,26.0,M,47.0,M,,0000*71
$GPGSA,A,3,20,01,11,17,,,,,,,,,2.6,2.4,1.0*34
$GPRMC,164655.000,A,5049.4957,N,00008.8945,W,0.09,24.77,180107,,*2B
$GPGGA,164656.000,5049.4959,N,00008.8946,W,1,04,2.4,26.3,M,47.0,M,,0000*7C
$GPGSA,A,3,20,01,11,17,,,,,,,,,2.6,2.4,1.0*34

These sentences aren’t too scary, once you have the NMEA descriptions. And as it’s Bluetooth and a serial connection, you can imagine it’s not too bad to get that data live on a phone, without the need for JSR-179 or JSR-293. Great fun.

But back to the talk, I should mention that the big thing OpenStreetMap has is a great refresh rate. Compared to other mapping organizations, OpenStreetMap contributors can, for example, spot new streets in their area as they are being built, meaning the OpenStreetMaps maps can be years ahead of the other players. On the other hand, organizations like the Ordnance Survey have a great advantage in precision. But what you need depends on what you want to do, and for OpenStreetMap the focus (I think) is about navigation.

Links to follow up: New Popular Edition (OS maps out of copyright); Neogeography; Free The Postcode; KML; Geonames; OS information; GPSBabel; Yahoo! allows satellite imagery in OpenStreetMaps.