wiki/ news/ 2012-09-14 - Successful quarter-scale comms test (~ 1 km)

Nathan, Glenn, Ian, Theo, Richard, and Kenny, Andrew, and Joe by proxy, tested the entire rocket and ground communications system. We spend the morning hacking away at the WiFi problem (we can't seem to get channel 36 in ad-hoc mode without associating with an AP first), and then we packed up our equipment and walked from the PSBA to the tram.

Glenn, Richard, and Kenny ran the TrackMaster 2000 on the new Gibbs bridge right by the tower of the Portland tram. Nathan, Ian, Theo and Andrew took the avionics module up in the tram to the observation deck of the OHSU hospital. Google maps claims that's about 912 m, so it was about a km which is 1/4 of our planned height in brothers.

Joe worked out that the regulatory database update interface gets wedged if cfg80211 is initialized before the uvent helper is available. This can be solved either by compiling cfg80211 as a module, or by compiling in a static regulatory db.

Summary: Success! We got decent ATV signals and WiFi pings in the tram, and then a solid connection with GPS lock when we were on the OHSU observation deck.

Note: The GPS didn't lock for a really long time. First off, we think the GPS battery may be toast and that it cold started. That still doesn't explain how long it took, however. Then using our phones we found out that the GPS constellation was pretty crappy, especially with the giant OHSU hospital building behind us blocking half the sky. Eventually, the satellites drifted into view and we got a solid 3D lock. We turned the WiFi and ATV power amps on and off in an attempt to see if they hit the GPS SNR readings in any way, and they didn't as far as we could tell. So we're not worried, but this probably warrants some more investigation into the GPS.

Photos

Working on the FC

Working on the FC

From the tram. Getting pings!

From the tram. Getting pings!

From the top of the OHSU Tram

From the top of the OHSU Tram

Aiming the trackmaster from the bottom of the tram

Aiming the trackmaster from the bottom of the tram

Getting a clear signal on the ATV

Getting a clear signal on the ATV

Map

From Google maps; the actual distance is greater because of elevation.

distance map