probably turn rock solid here then thanks for letting me no
My dynamic harmonics PR has been merged into master: https://github.com/ArduPilot/ardupilot/pull/14470
If you are using ESC telemetry then I would definitely recommend using this:
INS_HNTCH_OPTS=2
This gives you a notch per motor. You will also get a big benefit by raising the BLHeli t-trate (SERVO_BLH_TRATE), I am using 100Hz on an F7 without issue.
This change significantly reduces the noise generated by the notches, so you should also find that if you re-tune with it on you will get a much crisper tune.
With FFT you should also get better results as it will track all 3 FFT peaks, although this is more applicable to larger copters so not necessarily worth it on a small racer.
Finally if you touch nothing, you should still get lower noise/better performance from the increase in notch update rate and the fact that the low-pass filter is now run last.
Happy Fatherâs Day!
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So if I was using Double notch, disable that and enable âDynamic Harmonicâ only? If it makes a difference Iâm using FFT not ESC telemetry.
Itâs a bit mask. So you can set it to 3 to use both.
Knew it was a bitmask (MP has a selector menu for each in latest beta) but not if it was OK to run both. Thanks!!
At one point it wasnât safe as @rbachtell 's broken Solo will attest to 
So reasonable question - but safe now!
Wow, enabling all this goodness sure is effective! This is on my 5" 210 with a Pixracer, Dynamic FFT (no ESC telemetry), Dynamic Harmonic and Double Notch. I suppose Double Notch isnât required on this little guy?
Pre:
Post:
Hah, yeah pretty dramatic eh? Do another tune and fly, fly, fly 
I think on smaller quads the double-notch is counter productive - the peak is so pronounced that you want the attenuation that a single-notch can give rather than the breadth of a double-notch.
Roger that. I looked at the Load on the Pixracer and itâs ~53% max. No problem 
When you tune:
- Set FLTT to 0 first
- Set AGGR to 0.2
After you tune:
- Set FLTT to 30 or so
- Do NOT set ATC_ACCEL values to 0
Hi Andy,
Could I get your thoughts on my pre and post harmonic notch results?
Pre:
Post:
As you can see, thereâs a dramatic difference! Is there anything else I should do to further reduce the peaks?
I am currently running throttle based as my ESCs donât support telemetry.
| INS_HNTCH_ENABLE | 1 |
|---|---|
| INS_HNTCH_FREQ | 60 |
| INS_HNTCH_BW | 30 |
| INS_HNTCH_ATT | 15 |
| INS_HNTCH_HMNCS | 3 |
| INS_HNTCH_REF | 0.44 |
| INS_HNTCH_MODE | 1 |
Thanks!
Your primary harmonic is at 32Hz so you might do better to set INS_HNTCH_FREQ to that but use a narrow bandwidth - 15Hz say - to avoid control issues
You could also increase ATT to 40
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You might want to set INS_LOG_BAT_OPT to 0 (not 1) and re-test for better averaging/oversampling.
Of course Iâm just parroting what Mr. Piper said a few days ago
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Okay, thanks for your help Andy & Dave. Iâll give those suggestions a try
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I have a PhD, so technically itâs âDr Piperâ âŚ
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Excuse the error Dr. Piper, I should have know that!
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Good morning Dr Piper and Sir Dave lol,im going to have an other go at my 3 incher bloody health gets in the way,is there much difference between using FFT or the Harmonic tuning please
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Use ESC telemetry if youâve got it. Otherwise, FFT is better than throttle based notch.
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Yes, what wicked said. I have transitioned thru all of them. I donât have a craft flying with ESC telemetry now so in lieu of that Iâm using Master on 2 craft (a 5" and a 13") with FFT and itâs working very well. Both of these are âOK to crashâ though, Master wonât be best for all certainly.
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Thank you,Wicked and Dave will probably try and set up esc telemtry put need to get a new cable for my 4 in 1 esc