Pixhawk and some ESCs with Low KV motors. Pixhawk is not the problem. Problem is related to ESCs, Firmware and fine tuning.

Posted by Pmarche on July 22, 2015 at 9:03am

I Found a solution to the problem; I changed ESCs to Tiger Motor ESCs and changed the signal to 200hz.

 

More tunning on PID required, will try Autotune, however quad flies great on stabilized mode.

 

 

It is now clear that the problem is not related to PIXHAWK but to the ESCs and  signal processing by the motors . As previously mentioned by experts in this Forum, the signal for Pixhawk is always the same and the controller is not the problem.

 

7/27/2015

 

Ok I accidentally sent a message to all the group, but I meant to make a clear declaration about PIxhawk.

 

For some reason, no one has ever found a resolution with the motor sync issue with some ESCs,( in my case with hobbywing 40a and 60a and the sudden loss of control of the Pixhawk  due to signal malfunction with low RPM high pole count motors  ( t motor 4008 380kv).

 

I believe it is important to mention, that after tunning, changing ESCs checking motors, and a few minutes of Stabilize and Loiter flight mode flight, switching to Pixhawk has been truly disappointing, and everyone should no that it will take some time to reach the " industrial" reliability and end user friendliness of the DJI Wookong M in the Pixhawk.

 

I believe it will be possible, but when there are potential to date unsolved issues, the community needs to be aware of them, in order to create proper expectations of Drone Builders and developers.

 

Pixhawk is completely incompatible with hobbywing Pentium 60 a and Hobbywing 40a ESCs. It Flips on necessary roll adjustments, and the motors are completely out of synchronization, even after adjusting RC signal parameters, PID adjustments, ensuring good connections, and checking motors and ESCs.

 

I truly hope the solution will be using DJI or T motor ESCs; however, there is a lot of people that are likely to try Hobbywing, or other brand high Amp ESCs with large motors, and my message is:

 

DON'T try it!!

 

You will spend more money, parts and time and brain power than simply using another controller.

 

 

 

 

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Replies

  • ActionDrone April 26, 2016 at 1:16am

    I was looking for informations and confirmations about 3DR (original) Pixhawk reliability.

    Now the question is: I understand the modularity of the Pixhawk - I love it - but if we need a FCU for our professional works, why spend so many efforts and risk so much, when DJI has reliable and well renowned solutions ready to go without headaches?

    This is my comment BEFORE my first Pixhawk flight on a Tarot X6 960 exa, well built with T-Motor 40A 600mhz ESCs, 5008 motors, Tattu 10A 25C 6S pair of batteries, and some other good stuff on.

    Please let me know, I would like to fly safe.

  • Euan Ramsay August 12, 2015 at 9:27am

    Ok, so I've got a problem with mine...a different problem.

    After I found my flycolor 45A 3-8S units (http://www.hobbyking.com/hobbyking/store/__58267__Flycolor_45_Amp_H...) became unreliable in longer flights, I swapped to Luminier versions (http://www.getfpv.com/lumenier-45-amp-3-8s-esc-with-simonk-firmware...) to see it if improved matters.

    It did. Sort of. The rig flies so much better - rock solid in the air. BUT....now the ESC's are red hot after 20 mins. The flycolors were always cool. Motors and batteries are all fine. Got a call into Luminier about how to reprogram the timing, or even replace the firmware.

    Both ESC's are powering this motor (http://www.hobbyking.com/hobbyking/store/__74762__Multistar_Elite_5...) on 1855 CF props, and 8S.

    • John G. > Euan Ramsay September 23, 2015 at 12:18am

      I have the same ESC's and Motors and Hobbyking Pixhawk, but with 20" props. I plan on using 4S and 8S. I maiden'ed today with 4S and flew to 5' for 30 seconds and then it looked like one motor just stopped and flipped over, I suspect it lost sync. I have been emailing Flycolor and they told be to flash BLheli and maybe adjust the timing. But they couldn't tell me what Hex file to use :/.... It will be a few days before I can work on it. Will report back then.

    • John G. > John G. September 28, 2015 at 2:51pm

      Smoked the flycolor esc after loading blheli on it. So i'm moving to hobbywing.  Also FYI that the Lumenier 45A HV esc is identical to the Flycolor 45A HV ESC

    • Pmarche > John G. September 29, 2015 at 9:44am

      Try to lower the motor signal to 100hz. That also helped to solve the problem for me. Thanks.

  • Pedro de Matos July 30, 2015 at 1:30pm

    Today made three autonomous flights.

    After several calibrations and several tests, I came to an end with three (3) autonomous flights. everything working 100% with the Mission Planner.

    Thank You.

    Configuration:

    - T-Engine AIR GEAR 350 Set

    - Motor 920KV AIR2213 (x 4)

    - Prop T9545 (CCW CW 2 + 2) (9.5 x 4.5) (x 4)

    - ESC AIR20A 600Hz 3-4s NO BEC (x4)

    - Plate energy distribution

    - Multicoptero FPV

    - Battery Alarm

    - Battery V8 series 3s 5000mah 30C (DP5000XP30-3S)

    - Flight controller – Pixhawk / PX4 FMU v2.4.5

    - GPS UBlox M8N 10Hz

    - 3DR Radio telemetric

    - Pixhawk/PPZ/MK/MWC - PPM Encoder (*)

    Radio:

    - Issuer: JR - 6 Channel Model - XP652

    - Receiver: R600

    Total weight: 1.240 kg

  • Joe Dietrich July 30, 2015 at 1:24am

    I've been running DJI's E600 propulsion system on my Pixhawk hex with pretty good luck until recently (flight crash due to wrong PIDs using a heavier 6S battery than what I usually run on 4S).

    DJI's E600 system uses 20A Opto ESCs, 415kV motors, and 12"x4.2 props (good up to 6S).  I set the ESC signal frequency at 400Hz, and the hex seems to fly real nice (logging close to 100 miles of total distance over 30 flights), even the auto-tune process has been very crisp and sharp when I have used it.

    I'm still experimenting with the Pixhawk (changing it over to a quad due to the recent crash); I have just lost too many $$$ in the quirkiness of the Pix, and not getting the video rig I had hoped for (the DYS 3-axis gimbal I've been using just is not as good as my H3-3D on my Naza-M V2 F450).

  • Euan Ramsay July 29, 2015 at 5:32am

    Well, I have a more confusing issue.

    I'm running these ESCs:

    http://www.hobbyking.com/hobbyking/store/__58267__Flycolor_45_Amp_H...

    And these motors:

    http://www.hobbyking.com/hobbyking/store/__74762__Multistar_Elite_5...

    ...on 18" props and 8S. AUW 7kg.

    It flies ok for about 30 minutes...then it twitches...then a minute or two later, it flips and crashes. It even did this while in a nice stable loiter. Vibes are within tolerances, and I can't see any errors in the logs (will upload in a minute).

    I go and pick it up...fire it up, and all motors spin up normally. Even after 30 mins of flight, the motors and ESC's are all the same temperature - barely warm.

    Would this still be a sync issue?

    • Developer
      John Arne Birkeland > Euan Ramsay July 29, 2015 at 4:39pm

      Sounds like ECS battery voltage soft-cut protection, but a dedicated multi rotor ESC should not even have that option.

  • Pedro de Matos July 28, 2015 at 5:27pm

    Good friends, I've decided my problem. The PX4 did not want to fly, the low speed of the motors, then recalibrei all over again.
    The radio has been reconfigured and altered values were:
    TRV ADJ
    THR MIN -100% / MAX + 130%

    then calibrated in the Mission Planner radio and calibrated the ESC last.

    Functioning, I have done a test, it seems stable bad this windy where I live.

    My Arducoper:
    - T-MOTOR 920kv AIR2213
    - ESC AIR20A 600Hz
    - 3S 5000mha
    - PX4FMU

    Thank You

This reply was deleted.