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.
The radio is calibrated and we used Ardupilot from the very beginning. We only used Ardupilot because we wanted to use herelink for the RC (longer range than anything in the FPV world). Just a few days ago, we confirmed 14km video transmission range using Herelink with only 200mw. I’ll use it further next week on 600mw.
Also, since it’s been difficult to find true results of the Herelink range, I want to let everyone know that we achieved 14 KM video transmission range, broadcasting over water with just 250 mw. I’ll try again with 600 mw in a few days and see if we can get to 16 km. It’s surprisingly well. Very well… So far…