I need help trying to figure out why my hexacopter running APM copter (version 3.2, I think, but I'm not sure how to check) suddenly had a mind of its own. Here's what happened - you can see it all in the logs I've attached: I took the drone off in stabilize mode and flew it maybe ten feet away from the starting point. I then put it into return-to-land (RTL) mode for just a second, then switched back into stabilize. I flew it around in just a few feet radius for a little bit.
Then I put the APM back into RTL mode. The drone immediately went into a full tilt and starting accelerating and top speed, even though it was just a few feet from where I armed and took off. After realizing that the RTL mode clearly wasn't working right, I went back into stabilize mode, but the drone didn't respond at all. It continued going full speed ahead, then banking right before crashing into a tree.
I can't, for the life of me figure out what happened. I'm very amateur at reading logs, but I did spot check several GPS coordinates on a map and it had the location spot on. It also doesn't explain why, after switching back into stabilize, it wouldn't listen to the transmitter.
A few things I should note:
(1) I had an episode like this where I lost control before and crashed. I suspected it was interference, so I upgraded to an FrSky transmitter/receiver pair but that clearly didn't fix it. This time it also happened just after switching into RTL, so I think it has to do with the mode switch, not interference.
(2) After the first crash mentioned above, I decided to put on a geofence with a radius of only 20 meters and max altitude of 10 meters, so in case it went crazy, I figured it would keep itself nearby. I think the reason the logs say it went into RTL at the end is because it left the geofence this time, but I don't really know. I also don't think the geofence is the cause of this issue because this loss of control happened the first time when there was no geofence. I also GPS glitch detection enabled with the default settings.
I would really appreciate if someone could help me diagnose this. I'm completely lost on this and I am really scared to fly again until someone can help me pin this down. Thanks in advance.
you are running 3.2.1 per the log.....it looks like you had an EKF navigation failure but you didnt have extended logging turned on so there are no EKF details....EKF would explain the flyaway....
"02/08/2015 22:49:14 - 006101: EKF/ Inertial Nav Check ERROR: Bad Variance."
Oh shoot. I thought I had enabled full logging. I'll have to double check that. But that doesn't explain why I couldn't take control again, does it? After switching back into stabilize mode, shouldn't I still be able to guide it manually?
Thanks for getting me looking in the right direction. How did you find that error? I'm really new to log analysis.