P3S Litchi waypoint

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#1
This was the 2nd flight from the same location. Litchi mission went from AutoTakeoff to Waypoint to Atti. The only thing that changed on the csv file was the "flyStateRaw" 11, 14, 1. Anybody know what "flyStateRaw" is why and it would do that. Thanks
 
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#2
The only thing that changed on the csv file was the "flyStateRaw" 11, 14, 1. Anybody know what "flyStateRaw" is why and it would do that. Thanks
Your'e not providing very much information here. It would be nice to see the file in question. To answer your question initially "
OSD.flycState.RAW is the pure numerical value of OSD.flycState. If you look at the aforementioned 2 columns you will see that "11" is equivalent to "AutoTakeoff" etc..and so forth. Not really sure what you are looking for here, other than possibly to determine why the AC went in to ATTI mode during a mission.
 
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#6
FLY403 has compass and yaw errors. FLY404 has compass errors for the entire log. FLY405 is just fine. The compass errors are what causes the aircraft to switch to ATTI, along with your GPS health which was very low.
 
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#7
I guess the errors could be caused from the driveway with wire in it, but what about the GPS health? I thought I had plenty of satellites, and first flight was fine. Thanks for ur input
 
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#9
So strange since both flights were 15 minutes apart at the same spot. Is there an app/way to determine GPS health
 
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#12
do I need to send back to DJI in your opinion?
Not at this point. You should do some more test's, but this time in an open area that is free of any metalic objects. Re-Calibrate your compass there and do a quick test flight. If all is good, return to the spot you used for the above flight that had the compass issue. Do not re-calibrate for this second test. If this occurs again, then you will know what caused the issue to begin with. That is what I would do first.
 
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#14
This was the 2nd flight from the same location. Litchi mission went from AutoTakeoff to Waypoint to Atti. The only thing that changed on the csv file was the "flyStateRaw" 11, 14, 1. Anybody know what "flyStateRaw" is why and it would do that. Thanks
This looks to me like the usual launch-from-a-geomagnetically-distorted-location incident. Before launch the difference between Yaw and mgaYaw was about +11° since the Yaw value had been adjusted for the geoDeclination at the launch site. As the P3S began it's ascent it rose above the geoMagnetic distortion and Yaw-magYaw changed to -25°. That's a 46° change.
upload_2018-9-16_15-7-54.png


If Litchi can replay the flight I believe that it will show a -72° heading at launch but if you looked at the P3S you would have seen that it's actual heading was about -112°.

Looks like you launched from concrete which can sometimes have rebar that will cause a geomagnetic distortion.
upload_2018-9-16_15-21-56.png

Not, also the toilet bowling - a clear indicator of a geomagnetically distorted launch site.

I know you have launched from this site before without incident. The P3S magnetometer is in the bottom of the leg, almost touching the launching surface. And, the extent of the geomagnetic distortion can be small - 1 or 2 cm. So it's quite possible that a change of 1 or 2 cm will determine if there is an incident.

It used to be that the P3 series would switched immediately to ATTI when it sees the Yaw-magYaw separation. It seems that about a year ago the P3 FW was changed to use the same strategy used by the Mavic. I.e., the Mavcic. and now the P3, attempts to reconcile a Yaw-magYaw separation. If it can't the switch to ATTI is made.

The best, and easiest, way to prevent this type of incident is check that the Litchi map heading indicator is consistent with the actual heading. If not, then move to a better location.
 
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#15
Thank u both for the in-depth analysis of the problem, recalibrated the compass in a grassy area away for all metal, flown about 10 flights - A ok, thanks again.
 

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