Here are my logs:
https://1drv.ms/u/s!AplYZe-uqPEBguw20jAfODTg5PwzTQ?e=Vz3T45
That’s weird, should it be moving around a bit vs a straight line?
yes, I’d expect it to move a bit… Ive got a few questions, but I think looking at your logs will answer them… so I’ll check it out.
Let me know what you think. That was the log AFTER I did an autotune… If you want those I can post them too
What’s weird is I was expecting something like this, which I get from my HEX using the dynamic filtering
I don’t know exactly how ctun N is populated… Maybe the motors are spinning at a lower frequency than that, and so it isn’t getting any useful info and just staying at 80, which you have set as the frequency… which is the minimum it will look at.
Try lowering your frequency to 30 (30 is a random guess… but basically, try something lower)
The rpm data is available in the logs as well, not sure if you noticed that
I am not smart enough to translate the RPM to the frequency… I bet google would teach me, though 
I’d just try a lower ins_hntch_freq and see what happens.
Here is what the CTUN.N was during the autotune
So it did move a bit… But I will try 30…
Should I throw in the static notch filter while I am at it, or wait until we figure out the dynamic?
I’d wait on the static. Get the dynamic working first, and those other peaks might disappear.
OK so I will drop it to 30 and try a test hover. You want the unfiltered FFT right?
3300 RPM is 55hz. (Thank’s google) And you want something lower, so yeah, I still think try 30.
Just make a filtered FFT, so we can see if it’s working well.
And these are 320KVA motors Tarot 4114
Will do. Will post a hover in about an hour
Thanks for the help
Maybe 40 makes more sense than 30… Andy will have to fill in the details. There might be an upper limit to what is filtered based on that frequency. If you hover at 55hz, 40 is probably good for the low end.
Thanks, just wrote the params… Going for a test flight now
I would encourage everybody to take the time to understand how this works and not simply copy other peoples settings.
If you are using RPM feedback to define the frequency of the Harmonic Notch then you should set the minimum frequency to something that is low enough to cover your normal flight but no so low as to start to interfere with your control. I would suggest no less than 75% of your hover frequency.
For the throttle based frequency calculation, the settings of the harmonic notch define the minimum that the harmonic notch will go. This is defined by two variables the frequency and the throttle reference point. The harmonic notch will be set to that frequency when the throttle is at or below the reference throttle.
The harmonic notch frequency will increase based on the throttle when the throttle is above the reference value.
So if you want the harmonic notch to work from a lower frequency then you need to reduce the throttle reference by the correct amount. A formulae is given in the instructions on the wiki.
I would suggest that people don’t try to copy other peoples settings when using the throttle based frequency calculation and instead go through the process on the wiki.
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Post not relevant anymore, as things were clarified above…
It was my understanding that you could use either Throttle position OR ESC RPM which is why it was so important to set the correct pole number for the motors
INS_HNTCH_REF: Harmonic Notch Filter reference value
Note: This parameter is for advanced users
A reference value of zero disables dynamic updates on the Harmonic Notch Filter and a positive value enables dynamic updates on the Harmonic Notch Filter. For throttle-based scaling, this parameter is the reference value associated with the specified frequency to facilitate frequency scaling of the Harmonic Notch Filter. For RPM and ESC telemetry based tracking, this parameter is set to 1 to enable the Harmonic Notch Filter using the RPM sensor or ESC telemetry set to measure rotor speed. The sensor data is converted to Hz automatically for use in the Harmonic Notch Filter. This reference value may also be used to scale the sensor data, if required. For example, rpm sensor data is required to measure heli motor RPM. Therefore the reference value can be used to scale the RPM sensor to the rotor RPM.
Sorry, if you are using the ESC rpm then it is much easier to copy other peoples parameters provided you get the correct pole numbers.
I will reword the comment above to convey that!
My apologies I didn’t realise you were using that method.
@Leonardthall No worries at all. Being able to get RPM data was one of the main reasons for me to use BlHeli_32 ESCs
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