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multiple warnings to calibrate compass and remote disconnection

Thank you guys for the continuous effort to help me with this. Anything different that I could possibly look at than what was said before?
Since this is a Mavic Pro you could retrieve the .DAT from the MP. It may provide some further clues. Look here to see how to do that
Retrieving a V3 .DAT File from the AC

Looks like your MP has an older FW version. If so, when you connect the MP to your PC the internal SD card will mount as a drive on your PC. Just copy FLY076.DAT from that and then provide a DropBox link.
 
Since this is a Mavic Pro you could retrieve the .DAT from the MP. It may provide some further clues. Look here to see how to do that
Retrieving a V3 .DAT File from the AC

Looks like your MP has an older FW version. If so, when you connect the MP to your PC the internal SD card will mount as a drive on your PC. Just copy FLY076.DAT from that and then provide a DropBox link.
i am sure i have the latest firmware on my MPP as well as the crystalsky monitor that i use. These are all the logs and DAT files on that day. let me know if you see anything new.

Link:
 
The IMUCalcs stuff is computed by DatCon and provides a way to compare the IMU velocities with velocities computed by differentiating GPS position data. The .DAT from a mobile device is only 10 Hz causing the GPS derived velocities to be noisy. E.g., in this flight we have

View attachment 95658
where the IMU velocity is nice and smooth but the GPS derived velocity isn't. The velocityError data is set to true when the velocity difference exceeds the somewhat arbitrary value of 3.5.

Agreed, but I don't understand why the DatCon velocity difference is so much larger than I get doing the same calculation. Even without averaging I get much lower values:

datcon_vel_delta.png

vel_delta.png
 
Regarding my last post - so DatCon is differentiating the GPS position data with respect to time, rather than using the GPS velocity data directly?
Yes, that is correct. I'm aware that the GPS module computes a VelN and VelE but those are unavailable in the .txt. But, I wanted the IMUCalcs to be the same for both the .DAT and the .txt. I suppose that the differentiated GPS position values could be passed through a low pass filter to make them smoother.
 
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Yes, that is correct. I'm aware that the GPS module computes a VelN and VelE but those are unavailable in the .txt. But, I wanted the IMUCalcs to be the same for both the .DAT and the .txt. I suppose that the differentiated GPS position values could be passed through a low pass filter to make them smoother.

Right - that's the scheme I use for that calculation on txt logs. I just noticed that when looking at the DAT files DatCon still seemed to use that in preference to the GPS velocity data. That produces the differences that you see in the two plots in post #25, even without the rolling average.
 
Hi guys let me start by apologizing for the size of the Dropbox file below. DJI Assistant was not showing me the names of the different flights and just showed me the dates. Additionally, it seem to compress all the files that i checked into one DAT file. This DAT file is straight from the AC. Again i appreciate all the time that you guys are taking to help diagnose any issues on my MPP. See link below

Link: DJI_ASSISTANT_EXPORT_FILE_2020-03-04_09-40-10.DAT
 
Guys just to update, I went out to the east coast of where i live and it was pretty windy. After my last episode with multiple warnings, I did a IMU AND COMPASS calibration and used the same MAS props. I Happy to report no i had no compass errors. As i said i am just updating this thread.
 
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