Hi,
Recently I built two ardupilot (APM 2.5+) quadcopters with a friend. We are BOTH (two separate APM's) having the same strange problems: ardupilot keeps crashing at random, and we really don't know why. At this time, we already broke 4 quadcopter frames by this problem, and can't find the solution.
This is what happens: the quad starts shaking a little, and then all of a sudden, it starts turning and doing weird stuff until it finally crashes on the ground. This doesn't happen always, because sometimes we can just make multiple flights of +-15 minutes, and everything goes great.
The big issue is, that there is no clear cause of this. It just happens at a random time in flight, sometimes just while hovering, or sometimes when flying.
We use a APM 2.5+ together with a 3DR power module and ublox LEA-6 GPS with the latest APM firmware (3.0.1) and latest mission planner.
What we are (almost) sure of:
- Not a Lipo/power issue: we tried different lipos, and lipos were always charged. Enough capacity.
- Not a motor/ESC problem: all motors keep always turning when crashing
- Not a remote issue: we are using high-end futaba fasstest receivers
So it MUST be something with the APM... In the video below (and with all our crashes), all motors keep turning while crashing, so the APM is still controlling them...
Here is a video of our latest crash. First half of video is normal speed, second half is slow motion
https://www.youtube.com/watch?v=7mlFDNHcy1c
Anybody having same issues? Any ideas how to solve this problem? (maybe some kind of testing method?). If necessary I can provide some log files (I already looked into them, but can't find useful information)
Thanks for help!
Max
Replies
You can hand launch these systems without adverse effects? I know my other *unnamed" systems have very low tolerance for any movements after booting and before flight.. I am thinking about installing the Ardu on a multi...
The crash does look like a cold solder joint at a motor or esc all the same. Even though the motors are still turning, it does not mean they are doing so under full needed power...
the caveat is that you have two of these doing the same thing? if it was a coding issue, seems there would be a LOT of these complaints?
if this is a new bird, I would "re-flow" all of them although sort of a stretch, it is possible you both have the same solder job issue? Good luck! cant wait to see what was wrong here...
Do you have log of crash? It can help to debug your problem
I had several crashes early on when I was using bullet connectors. Vibration can cause momentary intermittent connections to the ESCs. It will happen so fast that you won't see or hear a motor stop or slow down. Sometimes you will see the quad try to recover as the ESC resets. Try soldering all ESC wiring.
Are you using the Power Module? If not, this is likely a brownout situation.