Setup Info:
Motors: GEPRC EM3115 900Kv
ESC: MicoAir 70A 4in1 AM32
FC: MicoAir H743 V2
Battery: Tattu 10000mAh 25C
AUW: Approx 2.2kg without payload and 4kg with payload. (After testing payload will increase)
Issue: The copter flies for 2-3 minutes and then suddenly all 4 motors stop spinning as if it was disarmed and falls to the ground. This has happened multiple times and also is a bit random.
With payload this kind of behaviour is a bit recurring. But when i fly the drone without payload it has sometimes flew for 20min straight without such failure and sometimes failed similarly. Maybe 50% failure rate without payload.
What i have already tried reading other ardupilot forums and articles:
Tried swapping both ESC and FC with Holybro Xrotor 65A 4in1 AM32 and SpeedyBee F4 FC. Still got the same failure.
Resoldered all major joints and changed the main xt90 plug to avoid power loss issues.
Tried changing land detection and crash check failsafe in parameters to rule out false detection cases.
Tried changing am32 settings to actual values like motor kv to 900. but kept other values to default as i have never experimented with them.
Note: In AM32 configurator Low voltage cut off, Temperature Limit, Current Disabled all 3 settings are set to disabled. Cannot find the Low RPM Power Protect setting in ref to another article.
I have a feeling that the problem is related to ESC heating or the AM32 firmware. But able to get conclusive evidence on it as settings like temperature limit is also disabled.
Both failure logs are attached
What AM32 version is used?
Try setting
switching from Dshot 300 to 600
MOT_PWM_TYPE,6
Get EDT data about temperature if available
SERVO_DSHOT_ESC, 3
and increase dshot rate if by some reason it’s not enough (there are some drops in looprate)
SERVO_DSHOT_RATE, 3
Although you have notch filters misconfigured and the noise plot looks strange it should not cause this problems. But take a look into your filters settings, bdshot works in “With 1.5Kg Payload.bin” log, but not in “Without Payload.bin”.
I think 2.17 am32 firmware is flashed. but i might be wrong need to check that.
I tried dshot 600 once but it resulted in my motors not spinning at all, so reverted back to 300.
the reasons of notch not being properly configured is because all the previous drones that i built performed well for my use cases with only the pid tunes and notch being left at default. so never went deep into tuning the notch filters. but i dont think improper notch tuning should be the reason of all 4 motors shutting down at once.
the reason of the non payload flight log not containing the esc telemetry like rpm is that the servo_blh_bdmask was not enabled. i enabled it later for the payload flight.
what i am planning to do next is just swap the esc for a speedybee 60A esc with heat sink on it. i guess it might be a thermal shutdown of the esc because of the cramped up space, motor wiring routed from above the esc mosfets, and the enclosure for the frame.
Although i am not that positive about this solution as the current esc has temperature protection off and even if esc is overheating it should limit the current in stages reducing power instead of shutting down.
the reason of me doing this is because, firstly i have limited time to finish this and also i read a similar article in which he had a similar failure and his esc heated to 120+ deg. Although i dont have esc temperature logged, my internal baro measured an ambient temperature of 55-60deg which was same to his.
Question: Will setting the esc type to AM32+EDT only enable temperature logging? or will it do something else also?
10in.param (21.5 KB)
I am attaching the Param file as well.
Why did the ESCs errored out and stopped? any solvable reason?
i checked the param file, the extra motor 4 is assigned to servo5 output, will it affect normal operations? One more thing to note that in AM32 Configurator it showed 5 ESCs instead of 4. I was baffled and ignored it thinking of it as some internal hardware which i dont know about. Could it be because of the extra output assigned in ardupilot? And can this be the reason for the ESCs to error out?
Yes, sure that’s why. The configurator see’s the output.
This mistake has been made before w/o issue. I would sooner believe it’s a Dshot, Dshot rate or AM32 config issue.
So you are saying that the 5th esc in the am32 configurator is because of the extra motor ouput assigned in ardupilot, But this will not cause the motors stopping issue?
I can try taking a test flight with the current setup and rectified params. But just need to clarify these things before risking one more crash.
Yes. But I don’t know if it caused the ESC errors, I would think not.
Remove the duplicate motor output
Configure for Dshot600
Try a Dshot rate of 2 (double loop rate)
