Based on the video, I think motor orientation was probably correct. The gains are just way off for the size of the copter. You can immediately see wild overshoots in the attitude control before it just can’t cope anymore.
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One other thing you will want to change is the compass priority. At present you have it set for the internal compass. Switch this in the compass setup screen. You will want to use Magfit to do a final mag calibration after the craft is basically flying. You can also set this right away:
INS_ACCEL_FILTER,10
And after you have a proper hover throttle value set these as per the tuning Wiki:
PSC_ACCZ_I
PSC_ACCZ_P
With a high thrust/weight craft as this is likely to be these can be important to reduce a output oscillation problem.
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@dkemxr, it’s my habit to also enable/tune harmonic notch filtering after establishing a successful hover, prior to any attempt at autotune. You’re a bit more knowledgeable than I when it comes to copter tuning, so I’ll defer to your advice if you disagree.
Managing Gyro Noise with the Dynamic Harmonic Notch Filters — Copter documentation (ardupilot.org)
Magfit is an outstanding tool, as well, but you have no battery monitoring enabled (it should’ve been enabled by default). The initial parameter setup will help with that. You need battery/current monitoring for magfit to be most effective.
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Absolutely agree. If you don’t you will just be back to another Auto Tune session when it is configured!
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Thanks. Yes it’s a very high thrust to weight ratio and it’s going to get even crazier. The next version will be X8. 
I actually do a lot more filter tuning than just that and run multiple iterations of autotune, per Andy’s video series, but we better avoid confusing things more for now!
If anyone has the time to devote, I highly recommend these videos:
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Alright, my extra parts are in and we’re looking to hire a tech to help us look over the gains and GPS settings before the next flight. Zoom or Microsoft teams should work…. Details to follow…
I disabled the internal GPS and set the external GPS as primary. I also changed the DShot protocol to 600 and recalibrated the compass 3x.
Existing problems:
We receive a compass glitch during each calibration.
I can’t get mission planner to save the cells of the battery and prop size (keeps reverting to 4S and 9” props).
I should be able to test it again tomorrow and this weekend but given the thrust / weight of the drone, I’d love to have a second pair of eyes go through the parameters before it takes off. It’s just too dangerous and expensive to crash again and again.
So we’re hiring. If anyone wants to assist with this, we have a solid budget set aside for troubleshooting this drone. Either that or we keep ordering new parts until we stop crashing. Haha
Let me know what y’all think?
Or GPS Glitch?
Wait for a good GPS fix before calibrating the compass but dont be too worried about a GPS glitch if the compass calibration succeeds.
You can always use a flight with lots of Yaw to refine the compass settings with a log file and MagFit.
Do you mean when you go into the Initial Parameters screen in MissionPlanner?
It doesnt read your existing values, it just allows you to put in new variables (prop size and battery cells) to calculate the new values to write to the FC - and it will offer up a window with changes if there’s anything to change. Usually you only ever need to run this once.
Can you post the latest log or param file now?
Just post the .bin file here from the next flight.
Our test flight was delayed today because of weather.
Tomorrow morning we’ll do a hover test.
We just went from the top and reconfigured everything from fresh rather than chasing parameter changes.
The biggest change was adding electromagnetic shielding between the PDB and orange cube. They’re mounted on opposite sides of a carbon fiber plate with EMF cloth sandwiched between. This brought the compass error way down.
I also pushed the ESC’s another inch away from the orange cube.
This configuration also reduced my wiring by quite a bit—shaved off 1/5 pound of 12 wire.
Also recalibrated ESC’s….
Let’s see what tomorrow brings.
Next side project I’m going so experiment with EMF shielding the PDB via partial enclosure. The housing will need to work in such a way that rain, dust and magnetic interference is mitigates but air is allowed to flow.
Message me for a consulting rate, if that’s what you think you need. I’ll happily offer the occasional advice without such charge.
Yes, I thought the initial parameters would have read my existing values–now I know.
I’ll have a new log tomorrow. Hopefully there’s no crash.
Another crash. Here’s two videos from different perspectives.
Crash log:
https://drive.google.com/file/d/19-YNoHtN6vi6aAiFZOf2rB718pt6aqdC/view?usp=share_link
Today’s goal was a hover test in position hold. My intent was to only bring it up 18’ AGL, hold, and come back down.
I kept the throttle in the pre-arm position for a bit. When I was ready to fly, I brought the throttle to neutral but the drone gained altitude.
Once I felt it was gaining too much altitude, I brought the throttle back down but the drone had its own mind. Eventually it just fell out of the sky (which I’m thankful for since it was becoming a safety hazard, gaining that much altitude).
My hands weren’t on the yaw on takeoff but I noticed I had yaw movement immediately on takeoff.
I’m stumped… It’s $300-800 every time I crash. I have enough props for one more crash.
Sympathies for the crash and any breakages - that’s never good.
This is a problem, I believe they are too high
MOT_SPIN_ARM,0.15
MOT_SPIN_MIN,0.25
MOT_THST_HOVER,0.2
You are currently just using PWM instead of DSHOT so set these first:
MOT_PWM_TYPE,6
SERVO_DSHOT_ESC,1
SERVO_BLH_POLES,14<- check and adjust to suit your motors
Then use MissionPlanner motor test to find the lowest smooth startup (percentage) value and set that as MOT_SPIN_ARM. With those ESCs it might be very low, like around 0.04 or something crazy-slow, so just make it 0.08 or whatever lets you see the props are all spinning in the correct directions.
Then add a bit, usually +0.03, and set MOT_SPIN_MIN
Also reduce MOT_THST_HOVER for now, since your copter seems a bit overpowered (as expected).
So you might end up with values like these
MOT_SPIN_ARM,0.08
MOT_SPIN_MIN,0.11
MOT_THST_HOVER,0.15
MOT_THST_HOVER > MOT_SPIN_MIN > MOT_SPIN_ARM
Definitely set this:
INS_ACCEL_FILTER,10
Now set up the battery voltage monitor, calibrate it and set these - this bit seems unrelated to the big problems, but please persist, it will definitely help.
BATT_ARM_VOLT,44.30
BATT_CRT_VOLT,42.00
BATT_LOW_VOLT,43.20
BATT_FS_CRT_ACT,1
BATT_FS_LOW_ACT,2 or 3
Apart from the failsafes, the battery voltage monitor is needed for the motor output scaling as battery voltage changes. This really helps tuning.
If you haven’t configured the voltage/current monitor for some particular reason (like too much expected current) then shout out about that, there’s a simple solution if you need it.
These are settings I would suggest next that should be quite safe and suit your copter size and prop size:
ATC_ANG_RLL_P,6.0
ATC_ANG_PIT_P,6.0
ATC_RAT_RLL_P,0.12
ATC_RAT_RLL_I,0.12
ATC_RAT_RLL_D,0.0055
ATC_RAT_PIT_P,0.12
ATC_RAT_PIT_I,0.12
ATC_RAT_PIT_D,0.0055
INS_HNTCH_ENABLE,1 // set this then refresh params to see the rest
INS_HNTCH_MODE,1
INS_HNTCH_REF,0.12
INS_HNTCH_FREQ,70
INS_HNTCH_BW,35
INS_HNTCH_FM_RAT,0.7
INS_LOG_BAT_MASK,1
INS_LOG_BAT_OPT,4
Not necessary right now, but it would be nice if you can hook up all the “telem” wires from those ESCs to one RX pin in a spare serial port on the flight controller, then you will have so much more information: RPM, temperature, current and voltage for each ESC. And the Harmonic Notch filter can then be based of the RPM instead of throttle. This could in fact replace setting up a conventional voltage and current monitor - let us know which way you want to go for further steps.
You’ll need these settings assuming Telem4 is used)
SERIAL4_BAUD,115
SERIAL4_OPTIONS,16
SERIAL4_PROTOCOL,16
INS_HNTCH_MODE,3
INS_HNTCH_REF,1
All his should help quite a bit with the control-ability, especially the MOT_SPIN settings. If you do a test and the copter still wants to get away on you, then add some dummy payload or put on smaller props at least for testing.
Keep using Stabilize mode to start the flight, then switch to AltHold as soon as you are happy with the control. AltHold will need some time to learn the new MOT_THST_HOVER value, so expect some throttle manipulation until that is completed.
Avoid GPS modes like Loiter or PosHold while you are in amongst those trees.
Let’s see the next .bin log file!
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Extremely helpful, extremely helpful.
I’ll have another flight tomorrow morning. Hopefully we have a flight and if not, hopefully a soft crash.
Thankfully this last crash landed in such a way that the payload took the fall. Broke all props but that’s all. Hell, I should start designing and selling crash kits.
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It’s flying! Rough, but it’s flying.
https://drive.google.com/file/d/1b9y_GXjlOO_0XbdheS_THiqjGv09bF1P/view?usp=sharing,
https://drive.google.com/file/d/1rR5ch5ltZV3W32idWDQrSuw4qCODJQuw/view?usp=sharing,
https://drive.google.com/file/d/1vjjhN4BXfLLTTV-4ogSjUsVA-Ag9wM44/view?usp=sharing
I still have to hook up the battery voltage monitor. I’ll do that tonight and have some more flights on Wednesday. Autotune should be Wednesday.
I havent checked logs yet, but if you get the ESC telemetry data working that can be your voltage monitor if you dont have anything else.
After the voltage monitor is enabled you can use Initial Parameters to set the correct voltage failsafe levels.
I use betaflight and Ardupilot. Ardupilot is very simple to setup even without any tuning if you run the right hardware. Looking at the video seems like you have not calibrated the radio make sure you have a new flight model just for Ardupilot. Moving from Betaflight to Ardupilot without calibration will be down right scary. The Tree should not be a big deal with a GPS but make sure you fly in Stabilize first then when you get a GPS lock test loitor. once you get the basics in the air you can tune more.
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Set these too!
Don’t skip any of the battery voltage failsafe settings either, once you get the battery monitor working.