Crashed my M2P... Can't figure out what happened

[sar104]

This looks like magnetic interference from the bridge. The yaw record in the flight log is clearly inconsistent with the yaw as seen in the video:



Additionally, the IMU record shows a sudden disagreement with the position data:



Positionally:



That clearly shows the uncommanded excursion to the east after passing under the bridge.



A full analysis requires the mobile device DAT file (FLY026.DAT).

How to retrieve a mobile device DAT file: How to retrieve a V3.DAT from the tablet

 

[Jwatts2344]

This looks like magnetic interference from the bridge. The yaw record in the flight log is clearly inconsistent with the yaw as seen in the video:

View attachment 83721

Additionally, the IMU record shows a sudden disagreement with the position data:

View attachment 83722

Positionally:

View attachment 83723

That clearly shows the uncommanded excursion to the east after passing under the bridge.

View attachment 83724

A full analysis requires the mobile device DAT file (FLY026.DAT).

How to retrieve a mobile device DAT file: How to retrieve a V3.DAT from the tablet

Wow, you guys are good!

I'm getting on that DAT file right now!

Thank you.

 

[Jwatts2344]

Ok... there's four DAT files with that date but not sure how to match up which file is the right one.

 

[sar104]

Ok... there's four DAT files with that date but not sure how to match up which file is the right one.

If there are four that include FLY026 in the filename then if you post all of them I'll find the correct one.

 

[Jwatts2344]

If there are four that include FLY026 in the filename then if you post all of them I'll find the correct one.

Here you are.

Thank you.

 

[Piglet3003]

Guys question.

If this happens and you hit the pause button on the controller would the drone stop and hover?

 

[Meta4]

Guys question.

If this happens and you hit the pause button on the controller would the drone stop and hover?

In normal flight it would, but when the drone is acting strangely because of a problem in the IMU, that problem would probably prevent the pause button from stopping the drone.

 

[sar104]

Here you are.

Thank you.

Another slightly strange Mavic 2 event. The bridge did introduce magnetic interference - you can see it in the magnetic field modulus and the individual magnetometer values at around 300 seconds:





That does lead to somewhat incorrect magnetic yaw values computed by both IMUs (the blue traces), but doesn't explain the 180° excursion in the IMU1 yaw value (the solid green trace):



It wasn't derived from the magnetometer data or the IMU1 rate gyro data:



It was the direct cause of the sideways motion and the resulting crash, however.

@BudWalker

 

[DanMan32]

I thought compass problems often resulted with calculated heading being 180 degrees off.

 

[Jwatts2344]

According to the Flight Record, it looks like the battery went from 99% to 84% in the first few seconds in the flight and stayed at 84% throughout the whole flight.

Is this the case or am I reading it wrong?

I thank all of you for your guidance and analysis.

Thanks.

 

[Meta4]

According to the Flight Record, it looks like the battery went from 99% to 84% in the first few seconds in the flight and stayed at 84% throughout the whole flight.
Is this the case or am I reading it wrong?

We've seen a few incidents lately where Phantomhelp log viewer shows similar and gives a false %.
The voltage is what really matters rather than the % indicator.
In this case, there was still plenty of battery at the end of the flight and there's no hint of any battery issue.

 

[Jwatts2344]

We've seen a few incidents lately where Phantomhelp log viewer shows similar and gives a false %.
The voltage is what really matters rather than the % indicator.
In this case, there was still plenty of battery at the end of the flight and there's no hint of any battery issue.

You guys know your stuff!

Thanks.

 

[sar104]

According to the Flight Record, it looks like the battery went from 99% to 84% in the first few seconds in the flight and stayed at 84% throughout the whole flight.

Is this the case or am I reading it wrong?

I thank all of you for your guidance and analysis.

Thanks.

That's an incorrect representation of the battery data. Both smart battery level and the voltage in the log file show the battery performing normally.