See the following video sequences:
https://www.youtube.com/watch?v=pCf0oY4hQpk&feature=youtu.be
This are sequences cut out from a 12 minutes flight. For those who would want to say"Bullet connectors for sure" please do not do that - how come it never twitches when it is in "loiter"? Only in "stabilized mode" and "Altitude hold" mode.
The beep you hear is an HK battery monitor indicating heavy load on the motor/motors when these happen.
See the logs also posted in the zip file attached.
Any help would be greatly appreciated.
Replies
Well, it took a while but the problem is solved. It looks like that no ferrite ring, no male to male servo cable could fix this problem. However Richard seem to have the winner answer: The problem is with the remote control.
My radio was a Turnigy 9x with a Spektrum JR DSM2 module in the back. The receiver was an Orange 9 channel receiver.
All that is gone now, it got replaced by a Turnigy 9XR with an EzHF transmitter and a EzUHF lite receiver and twitching is gone completely.
So all those with similar problems look at your RC link and try to modify it to something else.
Thanks for all the ideas, I will work on these one by one. I have the ESC's connected to the APM with all 3 wires still left intact, so all 6 ESC's bring in their own BEC voltage to the input rail. Once I tried removing all of them but one - but that didn't make any difference.
Jim, There are no lose cables, but adding ferrite rings to some of the cables is a good idea, I will do that, thank you.
Serge - I think this might be it, I have 1 set of cable - GND, Positve and Signal connected to Channel 1 and all other channels have only the signal pin connected. I will make some short Futaba type male to male cables and I will see if that makes any difference. Thanks for the idea.
Happened to me too, whatever firmware I used. Apparently the orange rx doesn't like the wires that come from the 3DR kit (crimped housing with the white, orange and yellow wires, and a single black/red wire to power the rx). Notice that it only twitches when you give an input from the RC. After I used the common female to female servo connectors, the twitching disapeared.
Hope this helps!
-Serge
I had something similar. It turned out to be interference from the ESC getting into the APM. I had left the cables connected to the APM for GPS and telemetry but neither accessory was connected at the time. Simply removing the cables solved the problem. This may not specifically address your problem but it does show the flight controller can certainly be affected by locally generated interference. Assuming you have GPS and maybe telemetry or OSD connected try removing the cables from the APM and see if it makes an difference.
I ended up relocating the APM up a level and putting toroids on the ESC, GPS and telemetry cables where they connect to the APM.
Good luck, intermittents are very difficult to track down.
Jim
Hi Richard,
I am getting some "twitching" during flights using the Spektrum DX18. When you recommended changing the speed of communication from 22ms to 11ms, can you explain where to make the change. Are you referring to the TX?
Thanks.