Help understand weird MA behavior: log analysis

[foobar34]

Aircraft Firmware: v01.00.0620
Remote Controller Firmware: v01.00.0200
DJI Go 4.3.36 on Android

A few days back my Mavic Air had a very weird behavior. I was flying from my roof deck, and I got a warning that there was wifi interference (lots of wifi router both in my house and nearby). I was not worried, as I was flying only 30-50' away. I'm in the USA, btw, so range should be better than EU

When I was ready to land I started getting the MA closer, and when it was only a few feet away from landing, lost the signal and started RTH. Then hovered over the home point, just out of reach. I literally had the radio (with the antennae properly oriented, side to the MA) within 3' of the MA and did not reacquire the signal, no matter what I tried. In the end I had to go up a ladder and manually "land" (i.e. I grabbed it and flipped to turn off the motors).

he app did not crash, and I tried a few things in the app, to no avail. I stupidly did not check the signal band used, mostly because with he sun on the screen of a small Android phone i was hard to see anything, and I didn't want to lose sigh of the drone for too long a time

Is there a trick to force a signal reacquire? I understand having interference, but the closest router was a good 20' and behind multiple walls/ceilings, so the MA transmiter should have been the strongest signal. Is there a way to get the transmitter to connect? I did not try to turn the remote control off and on, since I did not want to make things worse

I tried using DatCon to read the DAT logs, but the MA doesn't seem to be recognized. The TXT logs (which I could analyze) from the phone don't seem to have much info to understand why the MA disconnected

What's the best way to find out what happened on the model? What can I use to read the MA DAT logs? If preferred, I can upload the logs here

thanks in advance for any input

 

[itsneedtokno]

Upload the logs here

 

[foobar34]

Thanks. Uploading files from the Android phone. The device files are 100Mb and can't be uploaded. Should I provide a link to a Gdrive/Onedrive or is there a better way?

I actually managed to find some more info in the phone DAT file, and it looks like even if it had the home point recorded, the return point was a few yards away. You will see that the drone loitered for a long time over the final point, because I was desperately trying to reconnect.The weird thing I just noticed is that the phone kept recording the MA telemetry well past the control was lost, so it had maintained some level of connectivity, just not the ability to control the MA.

 

[itsneedtokno]

So I can't interpret those like others on this forum, but I knew logs would be needed for any analysis.

Just getting you ahead of the curve ??

 

[Meta4]

I actually managed to find some more info in the phone DAT file, and it looks like even if it had the home point recorded, the return point was a few yards away. You will see that the drone loitered for a long time over the final point, because I was desperately trying to reconnect.The weird thing I just noticed is that the phone kept recording the MA telemetry well past the control was lost, so it had maintained some level of connectivity, just not the ability to control the MA.

The flight data looks like this: DJI Flight Log Viewer - PhantomHelp.com

At 4:01.2 the flight data shows this message: QuickShot was interrupted. The aircraft will hover in place.
The drone was 112 ft from the home point and you flew it closer.
The last joystick input in the data was at 4:14.1.
You had flown back to a point 41 ft higher than the home point and 26 feet away from it.
Another message at 4:27.1 says: Camera Settings ActiveTrack Optimized.
But there is no joystick input recorded at all right up to the last data at 5:06.8 with the drone still 27 feet out and 40 feet up.
Did you try using the joysticks to bring the drone closer?

 

[hiflyer201]

I've been able to re-establish contact by turning off my phone and reconnecting. You said the app didn't crash so maybe you tried that. Both times that it happened to me it returned to a spot that was not a good landing spot so it just hovered. The top of my semi covered patio and the top of a concrete wall. In one case I had been flying it with just my phone and the other I was using my controller. In both cases I was very near the drone when it disconnected and I had lost the screen and control and the drone returned to home without climbing.

 

[foobar34]

The flight data looks like this: DJI Flight Log Viewer - PhantomHelp.com

At 4:01.2 the flight data shows this message: QuickShot was interrupted. The aircraft will hover in place.
The drone was 112 ft from the home point and you flew it closer.
The last joystick input in the data was at 4:14.1.
You had flown back to a point 41 ft higher than the home point and 26 feet away from it.
Another message at 4:27.1 says: Camera Settings ActiveTrack Optimized.
But there is no joystick input recorded at all right up to the last data at 5:06.8 with the drone still 27 feet out and 40 feet up.
Did you try using the joysticks to bring the drone closer?

Thanks for looking into this.

I was playing with quick shots (boomerang, if I remember correctly). At 3:19 it visually lost me, so it stopped. I restarted it, but still had problems, so I aborted the quickshot at 4.1. I decided to bring it in and land. But I lost control. And the flight lasted much more than 5 minutes, so the critical part has not been captured. The drone returned to what it assumed was home (for some reason it also had recorded the home point a few feet from the actual home point) and hovered there. I was literally 3-5' from the antennae, and I could no reacquire signal. It was quite unreal to have the remote so close to the drone and have no connectivity

So the phone log is really incomplete, and I would need access to the drone log

 

[foobar34]

I've been able to re-establish contact by turning off my phone and reconnecting. You said the app didn't crash so maybe you tried that. Both times that it happened to me it returned to a spot that was not a good landing spot so it just hovered. The top of my semi covered patio and the top of a concrete wall. In one case I had been flying it with just my phone and the other I was using my controller. In both cases I was very near the drone when it disconnected and I had lost the screen and control and the drone returned to home without climbing.

Yes, mine did exactly the same: without climbing returned to a bad spot for landing and hovered (return to home is set so that the drone climbs 30 meters, 100'; and I have all sensors enabled, so it could not land with obstacles, I assume; i also have precision landing enabled, and the landing pad was not in view from where the drone was) Looking at the track now, it's clear that it had mis-recorded the actual home point, and that explains the bad RH point (it did return to what it recorded as home point). Maybe it didn't climb because it was already close enough to home when it started RTH.

You will notice from the log that in the first minute I basically only climbed vertically (the only input the drone received), yet the drone track shows the drone moving right on the map and doing a part of a circle. There was no wind, so that's purely GPS drift. Clearly the drone did not get a good home point position, and once it lifted it acquired more satellites and the position drifted. But the drone was hovering right in front of me while I was futzing with the app to decide which shot to choose. That explains the bad RTH, and the sensors explain why it didn't auto land when it lost signal and RTH was triggered. Well, at least that part the MA did right, which is reassuring to know

So, given that I was wrong in a previous message and the drone actually lost connectivity and stopped recording the log on the phone, is there a way to read the MA log, or is that something only DJI can do?