esc ultra pwm problems


Are Xaircraft ESC's compatible to the ARDUCOPTER system? If so, I am open to suggestions. the xaircraft esc's use a different pulse-length range than regular esc's.

"Pulse width between 200us and 1200us can be used for power tuning. "

If you can set your range for the esc's in the firmware then you should be able to use them. this was also a problem with the OpenPilot?? CopterControl?? board but it was overcome by using the 200-1200 range.

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  • Were the modifications discussed by Ron and Aaron ever re-implemented in the main code?  I have XAircraft ESCs and an APM flight controller I'd like to use together.  I don't see an option in APM Planner or Mission Planner that has been added for custom ESC configuration, and wanted to make sure I hadn't missed something.



    • Hi Mike, this did not make it into the main code, and APM code has changed so much since this post that any original patch would probably not be applicable now. I haven't looked at at the low level pwm generating code for a long time, but if I remember correctly all you have to do to make it work with XA ESCs was something along the lines of subtracting 1700ms from the frame length.

      However, I strongly recommend against using the XA ESCs and stopped using them myself a long time ago (along with all other XA electronics except for their motors). Get yourself something with SimonK firmware like the excellent Afro ESC from HobbyKing. That way you can expect the same behaviour as the rest of the user community.

  • Best Regards
    I've been working with the Turnigy 10 amp and xaircraf series engines, highly recommend them very well balanced, I'm esc 490Hz in the response is very smooth withv2.5.4 new code, I tried to use the XAircraft unsuccessfully I prefer the Turnigy 10 amp.

  • The changes to the code to make Xaircraft ESCs work turned out to be trivial. They are at:

    this code is untested except on a single motor. By the way, I don't see why this "ultrapwm" is "ultra" since it's only 10Hz faster than ardupilot standard (I didn't even bother to make that change in the code) and has the same resolution...

  • Ok, I have successfully modified the code to properly drive Xaircraft Ultrapwm ESCs. I will upload the code in a bit once I make it a little less hacky...

  • Developer

    They are not as normal ESCs and all other RC gear is using 1000-2000us pulse widths. And ArduCopter software only supports normal ESCs as there are ready made kits like jDrones and other kits and then many people are using their own systems with random ESCs. 

    As ArduCopter software is fully opensource, it is possible to modify software to your needs. 

    jDrones, R/C UAVs and More....
    Manufacturer of ArduCopter frames and parts. Custom airframe manufacturing, Custom design services for all your R/C UAV needs
  • and we did work with CRIUS multiwii, changing settings on the board by Arduino.arducopter in this case can also be because in the Arduino programming through there is to know what values to change.

    rather what is the protocol to change in values

  • No they are not, we tried that and failed due to X aircraft using its own protocol, (we think)

    But if you ever do get it working please let me know.

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