Axis run away during a commanded movement

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1

Hi guys,
I’m Alessio an electronic/software developer based in Italy.
Everything works good: I can configure the motors, encoders and do movements as expected through the USB interface with a python script in closed loop position control.
The main problem is that sometime (it happend randomly) one axis (it happen only on M1) “go away” without any command.
The motion seem not to be controlled and seem to be done with a low current setting. The axis move really slow and if I push it there is no too much force. Does anyone can has a similar problem or any idea on how to debug?

Just some information about my configuration:

  • Odrive version: 3.5 - 48V with latest stable firmware
  • Motors: D5065 270KV
  • Encoder: CUI 8192CPR AMT102-V

Thanks in advance to everyone who will help
Alessio

2

This is often caused by noise on the encoder wires - can you check that the A/B/Z pins aren’t seeing excessive noise?

Also, are you getting an OVERSPEED error or a CURRENT_UNSTALBE error? (use dump_errors(odrv0) in odrivetool to check)

3

Hi Wemelon,
Sorry for the late reply but I was busy in other stuff with the same project. Anyway, I upgraded to latest firmware, changed the interface method and I no longer see the problem.

Just to answer to your questions (maybe the comunity need a feedback):

  • No, I attached an oscilloscope to the encoder lines (near the odrive board of course) and didn’t see any kind of noise (I used shielded cables for both motor and encoder, of course 2 different cables with different shielding). I cannot say that this is not the problem anyway cause I never experienced the “run away” again…
  • Errors: I checked for errors the firsts times it happend but I did not saw something particular, simply the axis stopped in the mechanical endstop.

If the error show again I will update the thread but, for now, it’s almost 1 month working 8hours per day, 5 days per week that everything looks good…

Thanks for your time
Alessio

------- EDIT ------

I forgot to mention that when I upgraded the firmware I lost all the parameters, so maybe the axis “run away” could be caused by a misconfiguration of something (maybe a integral windup or something similiar, I did not dive deep in the firmware so I consider odrive a “black box” at the moment)

1 Like
4

Awesome! Do you mind saying what kind of setup you’re using it in, or showing any pictures? It’s Always cool to see what setups work well for ODrive.