Mavic drifted out of control

[gulfrider]

I'll have to look at my flight logs however I mean as soon as I lifted off it was drifting. I'm wondering if it has anything to do with the update I just uploaded I mean at even 2 feet it was drifting

That’s exactly what happened to mine. Can anyone please help and tell me how i can read my flight logs?

 

[Keule]

Can anyone please help and tell me how i can read my flight logs?

Follow the link in post #13

 

[sar104]

Seeking help. I flew my Mavic earlier and soon as it launched it drifted quickly to the right without me sending input controls the remote. Here's the link to the flight logs - Log File Scared to fly it right now as it might do the same thing again. Any recommendations on what I need to do?

None of the three DAT files in that log (FLY049, FLY050, FLY051) are actual flights. You need to look at the txt log from your mobile device first. That may or may not include enough data to figure out what happened (quite likely not definitively if it was a magnetic interference issue), but it will include the DAT file record number.

As mentioned above, follow the instructions here to retrieve the txt log: DJI Flight Log Viewer | Phantom Help

 

[Bigbird48]

Please Post your flight logs HERE!!!

 

[BigRey]

That’s exactly what happened to mine. Can anyone please help and tell me how i can read my flight logs?

I found a few other posts about calibrating which I'll try when I get home.
I had made a fix to the Gimbal Vibration Abnormal message and just wanted to see if that was fixed so I wasn't flying for more than a few minutes noticed the drift and when I saw the same question posted I thought hmm wonder if the firmware update had anything to do with it ? hence my post
I'm at work currently and quite frankly to the people with the Please Post your flight logs really aren't helping the situation it's already been stated over and over so relax yourselves. WTF it's supposed to be a community, people post a friggin question because maybe there is an easy answer. I'm sure y'all ain't experts on everything

 

[Sky1]

Does GPS location changing due to additional satellites coming on-line making location corrections make the aircraft veer off like that? I would think it would only affect its RTH and flight records.

 

[rickw]

I found a few other posts about calibrating which I'll try when I get home.
I had made a fix to the Gimbal Vibration Abnormal message and just wanted to see if that was fixed so I wasn't flying for more than a few minutes noticed the drift and when I saw the same question posted I thought hmm wonder if the firmware update had anything to do with it ? hence my post
I'm at work currently and quite frankly to the people with the Please Post your flight logs really aren't helping the situation it's already been stated over and over so relax yourselves. WTF it's supposed to be a community, people post a friggin question because maybe there is an easy answer. I'm sure y'all ain't experts on everything

maybe when you post all info needed you might get proper response

 

[mefistofelis]

Where exactly did you take off? Was is reinforced concrete or steel?

 

[gulfrider]

Thanks for the information regarding how to download flight logs and have the analyzed through DJI Flight Log Viewer. It looks like it's a compass error. Please see link:

First Log
Second Log

 

[gulfrider]

Where exactly did you take off? Was is reinforced concrete or steel?

Last December i had compass issues from taking off at reinforced concrete. was able to correct that then. do u think that messed up my compass again? this time i was in the woods.

 

[sar104]

Thanks for the information regarding how to download flight logs and have the analyzed through DJI Flight Log Viewer. It looks like it's a compass error. Please see link:

First Log
Second Log

It was clearly showing compass errors, and if you compare the IMU data with the GPS data there is obvious disagreement - common for that problem:



Looking at the yaw data, the initial aircraft heading was recorded as 80°. On the ground that looks like the image below - do you recall which direction the aircraft was actually pointing at takeoff?

 

[sar104]

Last December i had compass issues from taking off at reinforced concrete. was able to correct that then. do u think that messed up my compass again? this time i was in the woods.

Taking off from a magnetically compromised location is not going to mess up the compass, it simply initializes the IMU yaw with the wrong value. When the aircraft takes off and the magnetic interference goes away (it's typically very localized - just a few inches), the compass and IMU then disagree - that's the compass error. You shouldn't even need to calibrate the compass - just move to a better location and restart the aircraft.

 

[gulfrider]

It was clearly showing compass errors, and if you compare the IMU data with the GPS data there is obvious disagreement - common for that problem:

View attachment 58887

Looking at the yaw data, the initial aircraft heading was recorded as 80°. On the ground that looks like the image below - do you recall which direction the aircraft was actually pointing at takeoff?

View attachment 58888

I'd like to say the aircraft was pointing East at time of takeoff.

 

[LuvMyTJ]

Alright guys, let's tone it down a notch or two. The thread has been cleaned as some members here got a little sideways. Let's remember we are here for the same reasons, to learn about these magnificent flying machines. As per the rules, Community Rules, we don't allow name calling, rudeness, etc. Please keep it friendly.​

 

[sar104]

I'd like to say the aircraft was pointing East at time of takeoff.

I suspect that it was not pointing east, because that was close to the initialized yaw value and it would not have generated a compass error. If you want to get the DAT file off the mobile device then we can take a look at the underlying magnetometer data which should unambiguously show what happened.

 

[BudWalker]

@gulfrider I can see that you posted your log files - several times. The Dropbox link you provided in your first post contains the .DAT created by the DJI Assistant 2. From that I extracted FLY046.DAT. It shows that the launch site was geomagnetically distorted.



Apparently you didn't provide any throttle until about 12 secs. At that point the MP started to ascend and there was a Yaw/magYaw separation - a clear indication that the launch site was geomagnetically distorted.

Looks like the actually heading at launch was west.

 

[sar104]

@gulfrider I can see that you posted your log files - several times. The Dropbox link you provided in your first post contains the .DAT created by the DJI Assistant 2. From that I extracted FLY046.DAT. It shows that the launch site was geomagnetically distorted.

View attachment 58965

Apparently you didn't provide any throttle until about 12 secs. At that point the MP started to ascend and there was a Yaw/magYaw separation - a clear indication that the launch site was geomagnetically distorted.

Looks like the actually heading at launch was west.
View attachment 58966

Good spot - I missed that he had posted that one earlier. That is the DAT corresponding to the flight above. 180° offset would be correct for a linear uncontrolled flight.

 

[BudWalker]

@gulfrider what's really interesting is that the MP appears to have listed off the ground without any control inputs. It wasn't until 11 secs that throttle was applied. Yet, the MP moved from here

to here


Does that seem about right?

Also, the MP didn't think it was airborne during this interval. This from the eventLog stream
-.356 : 3421 [L-TAKEOFF]alti: -75.748299 tors: 80.761948
.865 : 3482 [L-FLYMODE][Ctrl<2>] REQ_RC_COMMAND ASST_TAKEOFF ctrl_asst_takeoff
12.274 : 4052 [L-FMU/FSM]state changed. cur: in air

 

[BudWalker]

Good spot - I missed that he had posted that one earlier. That is the DAT corresponding to the flight above. 180° offset would be correct for a linear uncontrolled flight.

That's OK. Since yesterday I was trying to figure out why the MP lifted off without control inputs. Didn't even think about looking at the mag data.

Appears the MP just barely lifted off and then became a victim of it's mag problems.

 

[sar104]

@gulfrider what's really interesting is that the MP appears to have listed off the ground without any control inputs. It wasn't until 11 secs that throttle was applied. Yet, the MP moved from here
View attachment 58967
to here
View attachment 58968

Does that seem about right?

Also, the MP didn't think it was airborne during this interval. This from the eventLog stream
-.356 : 3421 [L-TAKEOFF]alti: -75.748299 tors: 80.761948
.865 : 3482 [L-FLYMODE][Ctrl<2>] REQ_RC_COMMAND ASST_TAKEOFF ctrl_asst_takeoff
12.274 : 4052 [L-FMU/FSM]state changed. cur: in air

It looks like auto takeoff, so that presumably explains the absence of throttle.