Drone log review


This will be my first post on this forum and I hope that I am clear with my question and provide the data needed to determine what my issue is. Yesterday, I attempted to fly a very large hexacopter and am running into an issue where it wants to lean upon takeoff. The lean is consistent and will only lean one direction. There was a GPS compass error which was fixed by replacing the module but now we are still getting errors when running an auto analysis on the logs. I am thinking this is an accelerometer-based issue or something to do with the GPS module setup. Just to clarify the drone has yet to make it off the ground. I am going to attach the 2 logs and any input or steps to work towards resolving this issue would be greatly appreciated.

I was unable to upload the files so they are in a google drive here is the link:Drone log - Google Drive


So you attempted to fly this “large Hex” with default parameters? And if it hasn’t made it off the ground then nothing much can be learned from the log.

Start with the Initial (pre-flight) Tuning parameters, or earlier, in the Wiki.:
Initial Tuning

Level the actual whole aircraft on the ground by shimming under the landing gear so the whole “prop disc” is perfectly level in all directions. Don’t trust your eyes or the ground, use a spirit level.
Then in MissionPlanner, Mandatory Hardware, Accel Calibration → press Calibrate Level

Follow Daves advice for the rest. More time getting it right on the ground will end up giving more time in the air and less time chasing issues and crashing.

To clarify this hex weight is approximately 180lb motors are 50kv running on 44v per motor. I was concerned about the possibility of large amounts of vibration messing with the accelerometer which is the reason behind the logs. I had the same issue with a much smaller drone and found this to be the issue. Another reason I was inquiring about the log Is due to errors popping up when I performed the auto analysis which I have not seen before. I am not too familiar with pulling logs and reading them so I am learning one step at a time haha. I have used the pixhawks before so I do belive it is set up initially correctly but I will run through it again!

I would double check for proper motor and prop direction.

Checked that multiple times, they are correct.

Get the voltage and current monitoring working correctly and accurately, then
Connect it to MissionPlanner and press Alt A and step through that dialog, or use this spreadsheet

But whatever you do that voltage and current monitoring will be essential, plus setting and testing the failsafes - this thing has the potential to cause significant damage and cost significant dollars.

Will do, thank you for sending the spread sheet.

The bold highlights are the failed tests that I was referring to earlier which I do not know what they mean

Size (kb) 5611.1728515625

No of lines 63497

Duration 0:03:31

Vehicletype ArduCopter

Firmware Version V4.1.0

Firmware Hash ea559a56

Hardware Type

Free Mem 0

Skipped Lines 0

Test: Autotune = UNKNOWN - No ATUN log data

Test: Brownout = GOOD -

Test: Compass = WARN - WARN: Large compass offset params (X:143.83, Y:-93.52, Z:-262.64)

WARN: Large compass offset in MAG data (X:143.00, Y:-93.00, Z:-262.00)

Moderate change in mag_field (28.69%)

Test: Dupe Log Data = GOOD -

Test: Empty = GOOD -

Test: Event/Failsafe = GOOD -

Test: GPS = GOOD -

Test: IMU Mismatch = NA -

Test: Motor Balance = UNKNOWN - 'HEXA/X’

Test: NaNs = FAIL - Found NaN in CTUN.DSAlt

Test: OpticalFlow = FAIL - ‘FLOW_FXSCALER’ not found

Test: Parameters = FAIL - ‘MAG_ENABLE’ not found

Test: PM = GOOD -

Test: Pitch/Roll = GOOD -

Test: Thrust = GOOD -

Test: VCC = UNKNOWN - No CURR log data

Auto Analysis is obsolete. It is of little value. Follow the configuration and tuning guidlines before attempting flight.

For example the error you highlighted MAG _ENABLE. That parameter hasn’t existed for years.

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I am no guru in reading the logs but your rear two motors are getting lower PWM readings that the rest as you throttle up. Have you calibrated the ESCs properly?

I did calibrate the escs prior to the flight. That is interesting though, couldn’t that be due to flight controller input.