Setting Harmonic Notch Filter

Today I did a test flight with the new parameters. I’m posting the .bin file. The vibrations in the Z axis exceed the threshold of 30, maybe because I was flying in a strong crosswind.

List of new parameters:
ATC_RAT_YAW_I,0.08 (was 0.195)
ATC_RAT_YAW_P,0.8 (was 1.95)
ATC_INPUT_TC,0.20 (was 0.15)
ATC_SLEW_YAW,3000 (was 6000)
ATC_ACCEL_Y_MAX,10000 (was 7000)
INS_HNTCH_ENABLE,0 (was 1)
INS_LOG_BAT_MASK,0 (was 1)
INS_LOG_BAT_OPT,0 (was 4)
PILOT_Y_RATE,50 (was 202,5) - new value is too low
PILOT_Y_EXPO,0.3 (was 0)
PSC_POSXY_P,0.5 (was 1)
PSC_VELXY_D,0.25 (was 0.5)
PSC_VELXY_I,0.5 (was 1)
PSC_VELXY_P,1.0 (was 2)
LOIT_ACC_MAX,600 (was 500)
LOIT_BRK_ACCEL,200 (was 250)
LOIT_BRK_DELAY,0.3 (was 1)
LOIT_BRK_JERK,300 (was 500)

Soon I would like to make Autotune in Pitch and Roll axes, I am waiting for windless conditions. Do the parameters described in the instruction:

have a direct impact on Autotune or can I treat them optionally?

The new parmers that I set up for Autotune are:
INS_POS1_X,0.115
INS_POS2_X,0.115
INS_POS3_X,0.115
INS_POS1_Z,0.089
INS_POS2_Z,0.089
INS_POS3_Z,0.089
PILOT_Y_RATE,90

Any suggestions are welcome.

In that last log everything looks quite reasonable, except there’s Y axis vibrations. That implies there is something affecting the flight controller directly, such as something touching it on one side or wiring pulled too tight in one direction. Or there is something that is vibrating in one direction, like landing gear.

Those INS_POS values are only required if your flight controller (or IMUs) are a long way from the centre of gravity (or centre of rotation) of your copter. Values are in Meters!
Setting them is a good idea if the FC is not centrally mounted.

It’s probably a good idea to also set the GPS_POS values too.

None of them affect the Y axis vibrations - that needs physical attention.

2 Likes

Thanks for your analysis. I’ll try to redesign the frame in terms of internal cable management and mounting vibration dampers/springs on the landing gear tubes.

There remains a question whether the following parameters affect the Autotune result?

  1. Calculate the Body Drag Coefficient
    EK3_DRAG_BCOEF_X
    EK3_DRAG_BCOEF_Y
  2. Calculate the Propeller Drag Coefficient
    EK3_DRAG_MCOEF
  3. Barometer Position Error Compensation
    BARO1_WCF_ENABLE
    BARO1_WCF_FWD
    BARO1_WCF_BCK
    BARO1_WCF_RGT
    BARO1_WCF_LFT
    BARO1_WCF_UP
    BARO1_WCF_DN

I dont believe they will affect the Autotune at all.