Lost drone

[lewish]

Hi guys I got this warning today and then lost all contact with drone. Opened find my drone and walked to the location which was exactly where it said the flight ended shown in the picture, but there was no drone, I spent 3 hours searching all around this location and it’s not there, there was no rth messages or anything it just went dead. I’m coming to terms with the fact the drones gone just wondered if you guys new if the drone would just carry on going after the flight records stopped recording

Thanks

 

[msinger]

Check out your TXT flight log to see if it explains what happened. You can upload and view it online here. If you'd like other people to review and comment on your flight log, then please post a link back here after you upload it.

 

[BD0G]

@sar104

 

[sar104]

Follow @msinger's instructions above.

 

[msinger]

 

[lewish]

Check out your TXT flight log to see if it explains what happened. You can upload and view it online here. If you'd like other people to review and comment on your flight log, then please post a link back here after you upload it.

 

[lewish]

DJI Flight Log Viewer - PhantomHelp.com

im a bit new to this so not sure what it all means

 

[SpinItUp]

Blocking trials effecting UAS control
#1

close but not close enough or it's been given a mega boost


The lay of the land looks like flying over the brow of a hill


seems to be flying from a room inside the house!!!
or that's the cause of interference

 

[sar104]

This is a bit different. The FC was definitely confused towards the end - I haven't seen a "IMU attitude error. Please check that the IMU is mounted properly." message before. If you compare the sensor fusion velocity with the time derivative of the GPS location (should be good since the navHealth was 5 with nearly 20 satellites) you see the following:



Note that for the first part of the flight the velocities agree very well. However, at around 115 seconds, following a brief (1 s) yaw maneuver that produced a recorded 70° turn, the aircraft headed off uncommanded to the SE and the velocities no longer agree. After that it was basically out of control. Looking in cartesian space the behavior, plus the discrepancy between GPS and IMU, are also clear.



Then it just disconnects, without any prior indication of signal problems, which suggests to me that the FC gave up and rebooted. If that were the case then it should have ended up on the ground around 50 m west of the last recorded point. Did you search that far over?

 

[lewish]

i will go back tomorrow and concentrate west of location, thanks for your help

 

[BD0G]

Keep us updated as I enjoy reading " I found my lost Mavic".
Flight controller gave up and rebooted? I never knew that was possible.

 

[Jackcutrone]

SAR104 continues to amaze (not mention flummox me what is Cartesian space, pray tell?)

 

[rfc]

SAR104 continues to amaze (not mention flummox me what is Cartesian space, pray tell?)

It's just a reference system defining a point in space relative to three perpendicular planes.

And I agree with you on SAR104; I appreciate being flummoxed at least once a day by him.

 

[sar104]

SAR104 continues to amaze (not mention flummox me what is Cartesian space, pray tell?)

Yes - apologies - it's just a fancy term for looking at the data in 2- or 3- dimensional orthogonal coordinates rather than plotting against time, in this case 2-D local north and east. I could have written that more simply but I was a bit rushed.

 

[lewish]

Well I have been all over the area several times and the drone is absolutely nowhere to be seen, oh well have to chalk it up to experience I suppose, thank you all for your help. What are your guys thoughts on separate trackers to put on a Mavic air

 

[apowen8976]

I have a Loc8tor fitted to mine on the bottom of the battery, if you can get the last known geo location the Loc8tor will detect within 120m radius so a slightly better chance of retrieving it....... Terrain depending of course!

Loc8tor Finder Tracker

 

[sar104]

Well I have been all over the area several times and the drone is absolutely nowhere to be seen, oh well have to chalk it up to experience I suppose, thank you all for your help. What are your guys thoughts on separate trackers to put on a Mavic air

It doesn't look, from the flight data, as if it could have reached the trees if the FC rebooted at the last recorded location. My estimate was a maximum of 50 m, shown by the red circle. However, we really don't know exactly what happened. Did you check the trees on the extrapolated flight path?

 

[lewish]

It doesn't look, from the flight data, as if it could have reached the trees if the FC rebooted at the last recorded location. My estimate was a maximum of 50 m, shown by the red circle. However, we really don't know exactly what happened. Did you check the trees on the extrapolated flight path?

View attachment 63237

i have looked at a roughly 200m radius from the original location and then payed particular attention to the westerly location that was suggested. the vast majority of the field has very small crop in it so the drone will be very easy to spot if it was in that area. on the other side of the trees to the west there is some longer grass but i have searched it as best i can, i have looked up in any trees and bushes around the location and it’s not there, i honestly believe it’s not in that location

 

[sar104]

i have looked at a roughly 200m radius from the original location and then payed particular attention to the westerly location that was suggested. the vast majority of the field has very small crop in it so the drone will be very easy to spot if it was in that area. on the other side of the trees to the west there is some longer grass but i have searched it as best i can, i have looked up in any trees and bushes around the location and it’s not there, i honestly believe it’s not in that location

It's certainly possible that the sudden failure explanation was not the reason for the disconnect, although that seems somewhat unlikely. If it really isn't within ~ 75 m of that location then something else happened. If you are interested in a deeper look then the inertial data and event stream from the mobile device DAT file might give some more clues.

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

 

[lolo780]

The best thing you could do is set up a mapping mission of the area using an M2P or P4P. Next best would be a waypoint flight shooting 4k video and play back on a big screen.

And this advice is too late for the OP, but if you're over a field and things get out of control, CSC stopping the motors should be considered. At least you can control where it drops and usually there's zero or minimal damage on a smaller AC.