Up ] [ APRS without APRS ] TinyTrak3 ] APRS BOX ]

I was thinking about how APRS technology could be used to assist in the management of an event even without the trackers having APRS equipment.

First, generate a list of key "waypoints" along the path that the event will follow. For the (bicycle) events that I have worked, we have produced a list of directions for our vehicles to follow; points on this list could easily be highlighted to indicate the "key" points.

As each HAM passes the key  waypoints, they relay this information to Net Control (generally, by voice).

At Net Control, there is a computer with Xastir running and the perl script below.

In the window where the perl script is running, someone at Net Control enters the HAM's callsign (or tatical call), followed by the waypoint ID (and optionally speed, course and comments).

The perl script will communicate with Xastir and create (or move) an APRS object representing the HAM.

As it stands, the script needs two configuration files to function; locations.dat and stations.dat. Locations.dat is the file where the waypoints are configured. The format is simple:

    ID,LATITUDE,LONGITUDE

Example: W2,3622.17N,08326.28W

Where ID is the Waypoint ID (just needs to be unique for the event), Latitude and Longitude are the latitude/longitude of the waypoints position (in typical APRS format, DDMM.MMN).

The Stations.dat file follows a similar simple pattern:

     ID,ICON,ALIASES

Where ID is the name of the station (can be callsign or tatical callsign), ICON is the two character APRS code for the icon to use with this object and ALIASES is a list of aliases for this ID seperated by spaces.

Example: WJMJEEP,/j,S1 SAG1 WMJEEP WJMJEP

The aliases allow for easier entry into the application while it is running. To indicate that WJMJEEP is at the Waypoint W2, Here's all I have to enter:

S1,W2

While you are in the program, you have some options; type help for a list of commands that are available. It will also take some command line arguments; type perl tracker.pl -help for a list of those.

Since I expect this will be used only on RF with a local TNC, I thought it would be a good idea to also display the packets that Xastir is sending out on the server port. For an easy way to display the packets, I used a modified version of the aprsdecu.pl file from G3NRW (available at http://www.tapr.org/~g3nrw). This option can be turned off by a variable at the top of the tracker.pl script.

Here is the current version of the perl script along with a sample locations.dat, stations.dat file and test.dat has a list of "commands" that can be entered to exercise the sample locations and stations dat files.

aprstracker.zip