Mavic Pro2 Falls from Sky

[sar104]

That’s for sharing the log. It’s weird the data just drops off that last line with no real warnings. I’m traveling and stuck on mobile so I can’t look at this too closely right now but am interested to hear more about this one.

That generally means that the FC process crashed or the power supply failed. It might be related to the over-heating problem causing the FC to shut down, but surprising that there are no warnings.

 

[Drone Master]

That generally means that the FC process crashed or the power supply failed. It might be related to the over-heating problem causing the FC to shut down, but surprising that there are no warnings.

The OP did not mention what two warnings he saw pop up.
I’m curious to know what they were.

 

[Drone Master]

That’s for sharing the log. It’s weird the data just drops off that last line with no real warnings. I’m traveling and stuck on mobile so I can’t look at this too closely right now but am interested to hear more about this one.

Yes, the same here.

 

[Cyberpower678]

Well right now what matters is determining if DJI will cover this or not. That’s what the OP is looking for and we need the aircraft DAT for that.

 

[sar104]

The OP did not mention what two warnings he saw pop up.
I’m curious to know what they were.

The warnings were:

• Navigation System Redundancy Switch (3 times)
• Gimbal Roll Reached Movement Limit

 

[sar104]

Well right now what matters is determining if DJI will cover this or not. That’s what the OP is looking for and we need the aircraft DAT for that.

The aircraft DAT is not going to help - it's encrypted. The mobile device DAT is readable.

 

[Joola]

Well right now what matters is determining if DJI will cover this or not. That’s what the OP is looking for and we need the aircraft DAT for that.

Only DJI can determine if they’ll cover it. Sharing with us only helps educate the community of potential issues and failures.

 

[IdahoJP]

Can you retrieve and post the DAT file from the mobile device? The log shows a sudden end, but there is an IMU switch that looks suspect shortly before that, followed by a gimbal error. Other than that there is nothing in the txt log that stands out as odd.




The aircraft DAT files are available in the "Log Export" section of DJI Assistant, but appear to be encrypted - same as the MA.

I hope I did this right for you,

 

[sar104]

I hope I did this right for you,
View attachment 45027

Um - that appears to be an image of a blank piece of paper. Well an icon actually.

 

[IdahoJP]

The aircraft DAT is not going to help - it's encrypted. The mobile device DAT is readable.

I get a error message.....The uploaded file does not have a allowed extension. Now what, Sorry

 

[sar104]

I get a error message.....The uploaded file does not have a allowed extension. Now what, Sorry

The file should have the extension .DAT. To upload it here just change the extension to .txt.

 

[Cyberpower678]

The aircraft DAT is not going to help - it's encrypted. The mobile device DAT is readable.

Did I miss something, since I last provided my services? I thought @BudWalker has a program that decrypts this information.

 

[sar104]

Did I miss something, since I last provided my services? I thought @BudWalker has a program that decrypts this information.

DatCon decodes the DATs from most DJI models, but not the MA or, now, the M2, which are actually encrypted.

 

[IdahoJP]

Um - that appears to be an image of a blank piece of paper. Well an icon actually.

The file should have the extension .DAT. To upload it here just change the extension to .txt.

Hope this is it.

 

[Cyberpower678]

Only DJI can determine if they’ll cover it. Sharing with us only helps educate the community of potential issues and failures.

We can also help attempt to determine what DJI will say, or should say. Those of us that analyze flight logs do know what DJI will likely do with it as well.

 

[sar104]

Hope this is it.

That looks good. Stand by.

 

[sar104]

Well that's strange - the DAT log appears to stop 15 s before the txt log. The first IMU switch is visible:

87.415 : 25495 [L-FDI]ULTRASONIC(0): fault off, disconnect
87.415 : 25495 [L-NS][AHRS] connect us :1
87.432 : 25496 [L-FDI]NS(0) TOF(0): fault off, disconnect
87.705 : 25512 [L-FMU/MOTOR]No need to disable motor!
87.741 : 25514 [L-VISION][VIO]receive vio data befor current ts||
87.744 : 25514 [L-NS][AHRS] Bad sample tick measure or recapture signal: 9.880000
87.744 : 25514 [L-NS][AHRS] connect vo :1
87.756 : 25515 [L-FDI]NS(0) VO(0): fault off, disconnect
90.291 : 25663 [L-NS][comm] ext ns connect2
90.299 : 25664 [L-FDI]NS(0) FUSION(1): fault off, disconnect
90.931 : 25701 [L-FMU/LED]action changed. Normal Flash:not converged(2)
90.931 : 25701 [L-FMU/LED]type:0, normal flash action:
90.931 : 25701 [L-FMU/LED]c0:0,15;c1:0,3;c2:0,13;c3:2,3;c4:0,10;c5:0,3;c6:0,10;c7:0,3
94.549 : 25913 [L-FDI]ns req:fdi,0to1,reason:normal,result:succeed
94.549 : 25913 [L-FDI][SWITCH] req:2,0->1,result:6,serr:7,derr:15
94.549 : 25913 [L-IMU]

state: drift
94.549 : 25913 [L-FMU/DM]Busy Device Changed. Type:imu1_ext_ns, <ID:7 idx:0-->ID:15 idx:1>, change ti
95.181 : 25950 [L-FDI]ns switch app warning!
95.419 : 25964 [L-IMU]

state: fixed​

​

At this time the IMUs disagree, as is evident in the pitch data:



Obviously this happens again in the final 15 s of the flight, but the DAT file stops before that.

After that there are multiple entries of the forms:

128.819 : 27921 [L-COMPASS][mag auto cali(0)] init|
131.707 : 28090 [L-VISION][VIO]receive vio data befor current ts||
196.539 : 31889 [L-GEO][fmu_api_handler_update_app_db]wrong index! 55|
​

I find all three of those in the DAT log for my M2P, although fewer of them. However, it looks to me as if something is causing the FC to fail - whether that is overheating or a firmware bug of some kind is hard to say.

Both IMUs report the same temperature (65°C), which is appears to be a set point - the IMUs on mine run at exactly the same temperature. The CPU temperature is not recorded as far as I know. Do you know if the fan works(ed)?

This looks like a clear case to request a replacement.​

 

[IdahoJP]

Thank you so much for your work on this. Not sure about the fan working I think so. I just glad its not something I did to cause the crash. Good news is I now have a forum to go to for good advice .I learned how to find and post logs ect. expensive education. Will get a hold of DJI in the morning . Thanks again for your time and wisdom.

 

[Cyberpower678]

Thank you so much for your work on this. Not sure about the fan working I think so. I just glad its not something I did to cause the crash. Good news is I now have a forum to go to for good advice .I learned how to find and post logs ect. expensive education. Will get a hold of DJI in the morning . Thanks again for your time and wisdom.

Given @sar104's thorough analysis, this is a clear failure of the aircraft. The IMUs lost calibration mid-flight, or failed, which resulted in some kind of FC crash. Based on previous experience, when the FC crashes the Mavic initiates some sort of catastrophic failsafe that shuts down everything internally. I'm assuming you lost RC connection when it happened?

 

[sar104]

Given @sar104's thorough analysis, this is a clear failure of the aircraft. The IMUs lost calibration mid-flight, or failed, which resulted in some kind of FC crash. Based on previous experience, when the FC crashes the Mavic initiates some sort of catastrophic failsafe that shuts down everything internally. I'm assuming you lost RC connection when it happened?

I'm not sure that it was really very thorough, with only the mobile device logs to work from, and the important one apparently incomplete. The DAT logs for the M2 in general, even when it seems to fly perfectly, seem to contain all kinds iffy-looking entries that I don't understand very well.