Hello friends
With the help of the PID review tool, I have understood why the machine has gotten a bit restless and also one of the motors on and off sounds like it would vibrate.
There are new bearings in all engines Gartt ML5008 330KV which drives 1760 folding propellers. There is a tricky hump in File 1 that was not previously present in File 2.
Happy weekend everyone
https://www.dropbox.com/scl/fi/k7kk0rte8lmfcba8ehw9n/1.bin?rlkey=ul79x33dfrh6ckm32nkjxcdxt&st=p7o79clq&dl=0
https://www.dropbox.com/scl/fi/2tcve77vccgriomb2mn3l/2.bin?rlkey=h3jd2scmfxz9s1q36a9yi1r31&st=8uiqko8p&dl=0
Log 1
There’s an oscillation in Motor3 and Motor4 outputs around 20:06:07 through to 20:06:26
Attitude control is not affected, nor vibrations. You would certainly be able to hear the motors.
Interestingly this “output” oscillation is NOT reflected in the ESC RPM either.
So I dont know what to make of it yet.
The only other thing of note is the pitch and roll angles are quite different at takeoff and landing.
If the ground had a couple of degrees slope that might be expected. Otherwise it could be worth levelling the copter across the tops of the motors by packing under the landing gear, then press “Calibrate Level” in MissionPlanner Accel calibration screen.
Log 2
There is no evidence of the same output oscillation.
Pitch and roll is still around 5 degrees apart at takeoff - best to do that level calibration.
Adjust these:
INS_HNTCH_FREQ,25
INS_HNTCH_BW,7
INS_HNTC2_ENABLE,0
Compass calibration could be a little better, in fact the internal compass is better than the external one. We’ll leave that until later though.
Firmware is 4.4.0, you could certainly upgrade to 4.5.7 (latest stable) and 4.6 will be mainstream soon too. Existing parameters will be preserved.
Let’s see how it goes with the firmware update, level calibration and those notch filter improvements.
Hi Shawn and nice to hear from you.
I changed the propellers from 1760 to 1655 and the vibrations went away. All propeller blades are without visible defects, but I believe that the 1760 blades have some type of manufacturing defect, all propeller blades are new. I live on a hill and the field below has a slope of a few degrees.
Here comes the last log
https://www.dropbox.com/scl/fi/bu99jwb8n7yj1qx63xreh/00000149.BIN?rlkey=8jk887677daok8x7ohd7kofwj&st=yk22xynh&dl=0
Vibrations are a bit better, and it doesnt hurt for the slightly smaller props to spin faster (than the bigger ones) - that will give better attitude control provided you dont go crazy on the payload.
Attitude control is very good. Let us know if you saw any issues.
That second notch filter is not quite right and it’s not really needed either, so you can definitely set
INS_HNTC2_ENABLE,0
The only thing I could see that wasnt quite right was the altitude, try these to settle down the altitude changes:
BARO_FLTR_RNG,20
EK3_ALT_M_NSE,3
PSC_ACCZ_I,0.4
PSC_ACCZ_P,0.2
This will fix up the compass too, but it wasnt bad before:
COMPASS_OFS_X,-1.3256413
COMPASS_OFS_Y,34.81226
COMPASS_OFS_Z,182.38742
COMPASS_DIA_X,1.0475229
COMPASS_DIA_Y,1.0528868
COMPASS_DIA_Z,0.8995903
COMPASS_ODI_X,-0.020952309
COMPASS_ODI_Y,0.027512005
COMPASS_ODI_Z,-0.022175984
COMPASS_MOT_X,0.71008366
COMPASS_MOT_Y,-0.32665524
COMPASS_MOT_Z,0.40437415
COMPASS_SCALE,0.9178169
COMPASS_ORIENT,6
COMPASS_MOTCT,2
Hi Shawn.
Thanks for the feedback.
How did you compile the ATT and RCout values into the same graph? Is there a template for the purpose?
I have repositioned the compass to be able to use a cover over the machine but haven’t updated the MAGFIT values yet. Attitude control feels better with smaller propellers. It remains for the Swedish rain to stop so it is possible to fly again.
Thank you so much Shawn and have a great weekend.
In the MissionPlanner log review graph you can left-click on one value (like GPS.HDop) and right-click on another (like GPS.NSats) and they will have different scales.
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Hi Shawn
I installed another li-ion battery and thought maybe I needed to redo the Magfit calculation. I thought I would start by doing the same calculation you did for me two months ago and this way verify that I am doing it right. I took the same file: https://www.dropbox.com/scl/fi/bu99jwb8n7yj1qx63xreh/00000149.BIN?rlkey=8jk887677daok8x7ohd7kofwj&st=yk22xynh&dl=0 and used ArduPilot MAGFit in flight compass calibration but I am getting completely different values than the ones I got from you. I am doing something wrong!.
My values become
COMPASS_OFS_X,21.470694
COMPASS_OFS_Y,18.996037
COMPASS_OFS_Z,84.56746
instead of
COMPASS_OFS_X,-1.3256413
COMPASS_OFS_Y,34.81226
COMPASS_OFS_Z,182.38742
Have a nice weekend