I just got my quad ready for initial flight testing today - everything works good at first, it's pretty solid, even with less than perfect weather conditions. However, after a few minutes of flying, it will flip over and crash upside down. (I didn't have it more than 3-6 feet up, so any flip would result in upside down crash.)
I am wondering if anyone has any suggestions?
Mode was "stabilize."
One thought - I noticed one of my ESCs is getting pretty hot even when the quad is not flying, just from the BEC functions I guess. (I have 4 linear ESCs tied together.) I am wondering if perhaps that ESC overheats and shuts down, causing a loss of power to one motor - and the quad to flip. The one thing about it is - after it's upside down in the dirt and I have reduced the throttle to zero, the motors are still trying to spin for a bit. If the BEC failed - could it cause a partial reset (while another BEC took over, or that one reset) resulting in this crash, and a few seconds to require the signal and detect zero throttle?
Next, I was wondering if it might be my radio tweaking out. I have a 2.4ghz FASST system, and a 900mhz 3DR telemetry radio. Think they may conflict? One thing, if I arm my ESCs, hold down the quad, and turn off the radio, the quad will "freak out." I would think a FASST system should not do that. Reminds me of the old 27mhz stuff.
Any other ideas/suggestions?
I've actually had something similar on APM2. I was flying the other day in stabilize (after attempting a mission in auto mode) and the copter flipped over and landed upside down with the motors still running (I had to unplug the battery to get them to stop). I fixed some of the damage (mostly plastic pieces and a prop) and checked out the copter real quick and then decided to try flying again and after hovering for a couple minutes, I attempted to switch to auto and the quad took off the wrong way. I then switched my transmitter to stabilize but couldn't control anything (the sticks didn't do anything). I tried to switch back to RTL and Auto and that didn't do anything either.
I fly with a separate BEC rated for 15A.
I have attached the 1 log file that contained data. None of the other flights appeared to have saved (possible culprit?). Initially couldn't connect on the terminal screen on the mission planner. I unplugged the sonar and xbee and was able to connect. I connected each separately and then together and haven't been able to reproduce that issue. The Terminal screen showed a bunch of ??? instead of the normal bootup. I guess right now I suspect that either the Xbee or dataflash card may be related to this problem.