2015-07-20 First field test
The run can be seen here.
I took a tour from my house to the office, through bus, railway and so on.
Two lessons learned:
- The battery lasted around 6 hours (after a 1h30 run during lab test). This is a bit short, so I'll put two batteries in parallel.
- Under some circumstances (actually, when no GPS data is available after having been available), the module report GPS coordinates (0,0), which the server reports, giving a point on the middle of the Atlantic with all the consequences in term of points in the map, calculated speed and distance and so on. As a consequence, the bug has been fixed in the MCU and the server side code has been hardened to reject these particular coordinates (!).
In preparing this run, I realized I was unable to tell if the MCU had been able to connect to the satellite modem. If I don't get any message, is it because of a poor view of the sky (I have many tall trees around my house), if some wires was disconnected, or if I was just too impatient. It turned out to be the latter, but having to guess isn't very convenient when you're in the field. So I added a LED blinking as soon as the modem starts answering.