Motors stop

Hello everybody,

I am just moving from multiwii to ArduCopter. My quad is flying fine but, at some random moment, the motors just stop for about 0.5second and start again (so, it seems the board isn't reset).

I am equiped with RC timer 30 amp ESC. They worked fine with multiwii. The board is powered by a UBEC. Any idea what to check to debug this problem ?

I'm quite sure it isn't a ESC problem so I would like to power it using one ESC (although the UBEC was OK for multiwii board)  but can I keep the +5v from every ESC or do I need to connect only one ?

One more question : With the multiwii , it is possible to define a minimum PWM to send to the ESC, to ensure they won't stop. It is possible to do the same with Arducopter ? I saw the THR_MIN but I don't understand it  (default = 130, unit = percent ? what does this mean?)

Thanks for your help.

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  • I believe using multiple non switch mode BEC's is OK.

    Is there no information provided on your questions in the Wiki manual?

  • Did you solve your problem? Main copter has same symptoms. One motor is dropping his power. Motors, ESC is directly soldered to wires (triple checked), no bullets. 

    Main configuration is 15x5.5 props, quad copter, skywalker esc 40a, hengli w48-22 kv 690. 

  • I'm facing a similar problem. My motors flickers every few seconds. They run normally then slow down for some milliseconds and back up. I have no clue... it could be ESC desynchronizing or something similar.

    I gave a bit of throttle and held the helicopter in my hands more or less stable (no big changes in pitch and roll) and faced this problem.

    Attached is the log and here a simple screenshot in case someone can understand this behaviour..


    2012-09-15 17-04 1.log

  • I am chasing this very problem at the moment with the 2.7.3 on an APM1, which I am assuming is a hardware fault I can't seem to find.

    Very 'twitchy' motors, and randomly chopping the throttle for about .5 seconds. If you have enough height it corrects itself.

    Also a 20deg roll to the right.

    l.ploumen does all of this sound relate to your setup?

    I have to add that 2.7.3 is doing a great job of holding everything together, in position hold it corrects the roll, in alt hold it only drifts +/- 1m.

  • Developer

    Sounds like a wire from the radio is broken and intermittent. If you had a Flash log I could tell you more.

    130 is 13% throttle. 


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