Go Home headed in wrong direction

[Traveler]

I am very interested to see how this plays out. Question, were these two events proceeded by flight maneuvers that were different than how you normally operate the phantom, or was each basically the same for how you normally operate the craft?

Thanks for posting this event!

 

[sinxa]

I am very interested to see how this plays out. Question, were these two events proceeded by flight maneuvers that were different than how you normally operate the phantom, or was each basically the same for how you normally operate the craft?

Thanks for posting this event!

I guess i flown it as the way i used to be, try to take aerial footage arround the village, didn't do any specific maneuver at all.

 

[sinxa]

here is my video showing those symptoms....

 

[Traveler]

I guess i flown it as the way i used to be, try to take aerial footage arround the village, didn't do any specific maneuver at all.

Thanks for replying so quickly.

When this happen to me, I stoped the RTH and flew back manually, but my fear is that this could lead to a flyaway, especially if the RTH was initiated by a loss of signal.

I do take some comfort in your craft eventually self correcting to the home point, but without repeated testing that proves it always turns back home, I remain concerned.

I look forward to seeing @meta’s review of your data.
Here is a pic with text on how my RTH went.

 

[sinxa]

Thanks for replying so quickly.

When this happen to me, I stoped the RTH and flew back manually, but my fear is that this could lead to a flyaway, especially if the RTH was initiated by a loss of signal.

I do take some comfort in your craft eventually self correcting to the home point, but without repeated testing that proves it always turns back home, I remain concerned.

I look forward to seeing @meta’s review of your data.
Here is a pic with text on how my RTH went.

the difference between our experiences are :
*) you intended RTH on your command, it went 180 degree from it supposed to be, and you still have connection all the time so you could canceled the RTH and bring it back manually.
*) i got RTH initiated by lost signal, it went somewhere else from it supposed to be, but then corrected by it self after a while, and i never realize that situation until i saw the footage, and it could go very wrong if it went to 180 degree as happened to you, because it would go further and i never re-gain connection afterward.

 

[Meta4]

Second time just happened this afternoon, its heading was about -30 degree from where it should, and it went about 80-100 meters GO-HOME run, and then it suddenly stopped and corrected the heading it self and then continue to the actual home point. Please check the screenshot above. The AC icon located on the point where it corrected it's RTH heading.

I have no idea what kind of circumstances bring this weird behavior to my Phantom4, but i just wondering what if someday it heads to somewhere further than the home point???

Until you upload the flight data, you'll never know.

 

[Neon Euc]

And I was just having a debate about this last night about RTH failures too.

 

[Meta4]

And I was just having a debate about this last night about RTH failures too.

RTH failures?
There's not much to fail in RTH.
Problems that may occur during RTH are usually related to the operator rather than RTH.

 

[sinxa]

If your Phantom loses control signal, that part of the flight would not be recorded by the app.
But if it shows in the flight record replay like you show above, it's in the recorded flight data.

If your Phantom loses control signal, that part of the flight would not be recorded by the app.
But if it shows in the flight record replay like you show above, it's in the recorded flight data.

I used to use the

Until you upload the flight data, you'll never know.

I used to use DatCon app to convert internal flight data into CSV format from my old Phantom3. But I still figuring out how to do the same with my Phantom4 since there is no "Flight Data Mode" inside the DJO.GO.app. I did get the flightData using the DJIAssistant2, but DatCon is no longer support it. Any Idea?

 

[Meta4]

I used to use DatCon app to convert internal flight data into CSV format from my old Phantom3. But I still figuring out how to do the same with my Phantom4 since there is no "Flight Data Mode" inside the DJO.GO.app. I did get the flightData using the DJIAssistant2, but DatCon is no longer support it. Any Idea?

No ... I just use the txt files from the app.

 

[sinxa]

No ... I just use the txt files from the app.

That's what i was talking above, how can we analyze something from the apps flight log if it's not containing any information when the signal lost occurred?

 

[Meta4]

That's what i was talking above, how can we analyze something from the apps flight log if it's not containing any information when the signal lost occurred?

You showed a screenshot from your flight record replay in post #14 above.
It's showing that the app has recorded what happened.

 

[sinxa]

You showed a screenshot from your flight record replay in post #14 above.
It's showing that the app has recorded what happened.

We are looking something happened when it lost connection, aren't we?
That's why i put a greyed screenshot inside the youtube video above to indicate that is the last situation before it lost connection. Have you check my video?

 

[sar104]

I used to use the



I used to use DatCon app to convert internal flight data into CSV format from my old Phantom3. But I still figuring out how to do the same with my Phantom4 since there is no "Flight Data Mode" inside the DJO.GO.app. I did get the flightData using the DJIAssistant2, but DatCon is no longer support it. Any Idea?View attachment 88628

DatCon does support it. Are you using the latest version (2.6.3)? Alternatively, just post the DAT file via Dropbox or similar.

 

[Meta4]

We are looking something happened when it lost connection, aren't we?
That's why i put a greyed screenshot inside the youtube video above to indicate that is the last situation before it lost connection. Have you check my video?

In both flight videos, you have a brief period of lack of signal that initiates RTH but you have full data recorded for the period before and after.
If you want answers, you need to look at that recorded data and the .txt file is the quickest and easiest to use.

 

[sinxa]

DatCon does support it. Are you using the latest version (2.6.3)? Alternatively, just post the DAT file via Dropbox or similar.

i was struggling run Latest DatCon 2.6.3 inside my PC for the whole night, but 2.3.0 just working fine. I don't know what's wrong. Is this the correct .DAT we're talking about?? Thanks for your reply....

 

[sinxa]

In both flight videos, you have a brief period of lack of signal that initiates RTH but you have full data recorded for the period before and after.
If you want answers, you need to look at that recorded data and the .txt file is the quickest and easiest to use.

Okay then, we'll try to post that TXT first.... i wish we find something inside it...

 

[sinxa]

Here is the LOG for 1st footage : DJI Flight Log Viewer - PhantomHelp.com
And this is for the 2nd footage : DJI Flight Log Viewer - PhantomHelp.com

And this is the video contain both footage :

 

[sinxa]

UPDATE !!!

I think i have a good feeling on this and by now i consider it as a new feature rather than an issue.... While i was googling arround searching for any clue about getting Phantom4 internal flight log, i found this DJI Phantom 4 Pro official video. It says that RTH will trace the last flight path backward and will continue with straight line to the homepoint after the connection is back, maybe this routine only applied for failsafe (lost signal) RTH only, not for the RTH by command button.

Then i went out of my house to make sure and flown a simple path so the AC lost signal blocked by some building in my city. And guess what, it really went back along the last path until it connected again. That's why the video show the AC stoped for a while waiting for RC's command wheter to continue the mission to another trajectory or back to home point safely.

I will make another test again about this, and i think i need to try to fly it along some curved path, and then i will turn the RC completely off, and let's see what kind of movement it will make.

If this is true, i might missed some DJI firmware update news about new features applied on my old Phantom 4, because i never heard this before.
Sorry for ruining this thread with something i don't understand.

 

[Meta4]

First time it happened 3 days ago, its heading was about -30 degree where from it should, but fortunately corrected right away before it started the GO-HOME run, i saw it on the recorded video on the SDCard,

The first flight you posted shows you flying straight out until you lose signal at 4:40.1.
After 7.2 secs the video signal resturs at 4:47.4 with your Phantom already returning on the exact path to the home point.
The video shows that there was a slight pause as it turned but the Phantom never flew off in the wrong direction.
It appeared to act exactly as it is programmed.

Second time just happened this afternoon, its heading was about -30 degree from where it should, and it went about 80-100 meters GO-HOME run, and then it suddenly stopped and corrected the heading it self and then continue to the actual home point. Please check the screenshot above. The AC icon located on the point where it corrected it's RTH heading.

Your second flight shows you flying out until you start to lose signal.
There are a number of breaks in signal at 8:01.5 (1.6 secs), 8:04.2 (7.7 secs) and 8:11.9 (26.2 secs).
When signal is restored at 8:38.1 your Phantom is in RTH and has flown 100 metres closer to the home point.
It is returning on the reverse of the course it was travelling when signal was lost.
At 8:53.5 it stops suddenly as the pitch indication shows.
At 9:03.04 it turns about 30 degrees while stopped and resumes flying toward home.
This appears to be doing exactly as it is programmed to.
On losing signal, it has retraced the path it was on and when it acquired signal, it has commenced a straight line RH to the home point.

I have no idea what kind of circumstances bring this weird behavior to my Phantom4, but i just wondering what if someday it heads to somewhere further than the home point???
I wish DJI acknowledge this problem.

I can't see anything to worry about and there's nothing DJI need to do.
Your Phantom behaved perfectly both times and never was in any danger of getting lost.