Komar Mitochondrik UAVCAN Integration

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I feel like I have read almost every post on this forum, but I cannot find any in depth answers, especially regarding the Komar Mitichondrik.

I have tried to integrate the Komar Mitochondrik motor controllers on my craft for a few weeks now. I am using UAVCAN for my communication protocol. I have had a problem that I have never encountered whilst integrating these ESCs. My quad copter takes off and hovers beautifully, and can hover indefinitely. The craft can also yaw from left to right, without any issue. When I ascend or descend the craft, it acts like it stalls and flips to one side. This ONLY happens when ascending and descending the craft. A few specifications that should be known for the craft:

  • Batteries: 2x 12s 10900mAh batteries, 120C output
  • Motors: KDE 7208 135KV (rated at no more than 2100W Max)
  • Propellers: KDE 24.5"
  • All-up Weight: 11.4Kg (~25 lbs)
  • Total Current Draw at takeoff (according to mauch current sensor): 40A
  • Total Current Draw at hover (according to mauch current sensor): 26A

I am using arducopter 4.0.4beta firmware, which I have used on other crafts recently. Here’s a few things about the autopilot and data collected from each:

  • Flying In guided mode with a companion computer
  • Vibration<7m/s/s
  • No failsafes or warnings
  • UAVCAN ESC configuration using the Komar Mitochondrik controller
  • MOT_THST_EXPO set from ardupilot documentation based on motor specs

I set the motor controllers up using this quick start guide (hoping there were not to many differences):

Quick start guide for Myxa

At first I thought it may be a power issue, but I read through this document and applied it to the Komar specs, and it seems I am within spec:
https://forum.zubax.com/t/max-current-watts-power-data-sheet-discrepancy/1135/4

One other issue I am having is that not motors spin up at the same time every time during the arming sequence. I am not sure what is happening here either, although given a couple of seconds they all do eventually spin. I am thinking there is some kind of correspondence here.

I have attached the configuration files for each of my motors, everything seems consistent to my knowledge, but I feel as if I may be missing something if anyone could take a look at this I would be more than grateful! I am here to support the UAVCAN system and aid in hardware development! Thanks!

Motor1_config File.yml (2.2 KB) Motor2_config File.yml (2.2 KB) Motor3_config File.yml (2.2 KB) Motor4_config File.yml (2.2 KB)

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Hi Austin,

If I understand correctly, you have a dynamic stability problem. In any case, I advise you to try capturing in UAVCAN GUI Tool the rpm step response plots on the ground.
If you are experiencing stability issues, then try adjusting the response as described in the post.

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@anon81208224.

I apologize for the delay, as this project was put on hold for another. I have just been reassigned today.

should I have the propellers on while running these tests? I am concerned with safety here at work, as this craft makes 80lbs of lift

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Hi Austin,

The propellers should be attached because you need to tune the response under the load. If you cannot securely fix the drone on the ground and are afraid for safety, then try fixing just the motor with the propeller and tune the controller with it. The autopilot is not required to tune the controller response. Then you can save the PID speed controller parameters and write these values to the other axis controllers.