Tuning the Harmonic Notch

I think you need to start your own discussion for all this, rather than put it all in the Harmonic Notch general discussion.

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Start your own discussion since this is not related to the harmonic notch filter

check my notch setting comment any suggest
frame : own made 450mm
fc : pixhawk 1
esc : 35A 2-6S Blheli_S DSHOT600
motor : ready to sky 2212 920kv
https://drive.google.com/file/d/19Z0N6dL-oLxSIkU5rJy2vSz_BAdPkykZ/view?usp=sharing

For DSHOT to be effective you need to use the AUX outputs for motors, not the Main outputs.
I would advise to use the bi-directional DSHOT firmware, then set the HNOTCH to use ESC RPM data:
INS_HNTCH_MODE,3
The params I recommend below can still be used if you get DSHOT working.
Look for a message in MissionPlanner Messages like:
RCOut: PWM:1-8 DS600:9-14

With the existing config, set these:
INS_HNTCH_REF,0.16
INS_HNTCH_FREQ,77
INS_HNTCH_BW,38
IINS_HNTCH_OPTS,0
INS_HNTCH_HMNCS,7
INS_LOG_BAT_MASK,1
INS_LOG_BAT_OPT,4

Please also set
BATT_FS_CRT_ACT,1
BATT_FS_LOW_ACT,2 or 3

EDIT:
INS_HNTCH_FM_RAT,0.7

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2

4
5

JazzMaverick BLHeli_S firmware flashing old ver J-H-30, 16.7
motor pin move to main pwm to aux just setting changes servo output 9,10,11,12 motor selection
BRD_PWM_COUNT not showing SERVO_GPIO_MASK = 0 motor aux work

after weekly holiday test fly

Don’t use the double-notch

INS_HNTCH_HMNCS 3 ok ?

after all setting change esc rpm showing in log ?

Depends on what your FFT shows. 3 ok for two-blade props

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today flying

after switch poshold hold,loiter,land mode quadcopter climbing high
compass/motor calibration Done interference 30
frame 450 fc pixhawk 1 gps m8n
error
ekf variance
vibration compensation on/off
gps glitch or compass error

mission planner screen recorder and bin file attach
https://drive.google.com/file/d/1sy6TCHgjc63EE0EwYFB64iSFTrc4l5ub/view?usp=sharing
https://drive.google.com/file/d/1nvwrHUTgTzsKM0FKyy4SCajnriYH5nwZ/view?usp=sharing

@dkemxr last work changes
965 topic
after facing problem

next all change default normal
sd card format ,install plane firmware and again install copter firmware,blheli firmware default, motor output pwm . notch disable

and today fly again same issue

There is definitely high vibrations and your flight controller (IMU) is sensitive to these levels.
I would say you need vibration values below 15, it looks like every time it goes over 20 you have trouble.
No amount of software filters will fix this - you need to do more to reduce the physical vibrations or isolate the flight controller.

Plus you have other problems too
image

So try doing all the mandatory calibrations again, go outside and wait for a good GPS 3D Fix before doing the compass calibrations.
Or get a new flight controller.

today fly after all reset default all tuning setting default
:sob: but same issue only stabilize mode work
poshold,althold,land mode going high vibration after roll/pinch rc input

https://drive.google.com/file/d/1MhpzBNnZ-80_ISSEuI6EuKjs3g_X8prI/view?usp=sharing
https://drive.google.com/file/d/1NuUT3Y3b-0gLolddNtcodSHs1eoaORb0/view?usp=sharing

cant buy new flight controller
can other option any eternal sensor, peripherals buy and mount

Did you change the wsy the flight controller is mounted? Or do any other physical changed to reduce vibrations?

Foam tape is insufficient for this craft, you need something much more compliant like a ball mount. Even Zeal Gel would probably not work but you could try it.

Are those aluminum arms?

Yes almunium arm and base f450 frame
Extra battery and fc mount wooden plate

New shock absorber added

I feel your cables/modules above and surrounding the FCU are creating unnecessary vibrations. consider securing it down.

My 2cents
years ago we used a hex copter where clearance between props tips was 1" or less
 it was horrible to land and would eratically move up and down as it neared ground
it is partially why i started building my own copters
my designs are all run through ecalcs
the x8 and quads are all ±18" square to motor center with 12 1/2 to 13 inch props
 ecalcs flags a couple of these because they miss clearance by 1/2" or less
 i.e. they all have 5" or more between prop tips
i have yet to see any of them have issues with ground effect
 not sure the reasoning
 or if this has an effect
but with the help of this community all 4 of my uavs are still flying with no major issue to date

today fly

fft test log
mask enable
https://drive.google.com/file/d/16ee4sTFBEDVMpjn6ISIJ1sVcEDHtAJxI/view?usp=sharing

mask enable
fft off harmonic off
look fft graph
https://drive.google.com/file/d/132MpV8w6diFzLYSve7xbHLhq1qKvSKeA/view?usp=sharing

I want to do a throttle based setup

In “9fft hover.bin”
The in-flight FFT actually picked up on the base frequency quite well.
So if you wanted to use FFT you would set these:

INS_HNTCH_ENABLE,1
INS_HNTCH_HMNCS,3
INS_HNTCH_MODE=4
INS_HNTCH_REF=1
INS_HNTCH_OPTS=2

There is a bit of spread to the frequencies though because you have some sort of weight or yaw imbalance causing motors to run at all significantly different RPM. Best tp carefully check your motor alignment.

To use throttle-based notch you would

FFT_ENABLE,0
INS_HNTCH_ENABLE,1  // set this then refresh params to see the rest
INS_HNTCH_MODE,1
INS_HNTCH_REF,0.224
INS_HNTCH_FREQ,74
INS_HNTCH_BW,40
INS_HNTCH_FM_RAT,0.7

Looking at the second log “13 fft off”, the result is the same - you would use the same throttle-based HNOTCH settings.
The broad spread of frequencies is still there, so definitely look at the motor mounts and alignment.
If you can fix that you would be able to refine INS_HNTCH_FREQ and INS_HNTCH_BW

No matter which HNOTCH method you choose, set this in all cases
INS_ACCEL_FILTER,10
(I see you did this in the second log)

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