Little anomaly with finishing waypoint missions

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I have a P3 Advanced and have begun playing around with Ultimate flight and waypoint missions. Everything works as expected and I am still discovering little features. I have noticed one annoying little thing though.

You always have an option at the end of a mission with almost all the software packages out there. I just chose to let Ultimate flight auto land when the mission is over. I set a first and last waypoint in the middle of my front yard and expect the bird to behave something similar to RTH.

I have noticed that the last waypoint where it wants to land is nowhere near as accurate as RTH has been. With RTH you can usually plan on the bird landing within 6 or maybe at most 10 feet of takeoff point.

When I have used "land at last waypoint" it has tried to land on the house, then on my car then in the street. ? ? ? I set my last waypoint in the center of the front yard, but the bird tried to land maybe 20 feet away from where I thought it should land.

I presume the waypoint is just not as accurate as the Home Point set at takeoff. I have had Litchi also for months but have been hesitant to use it, as I am not ready to replace my Phantom yet. (there are just too many posts with 'lost' and 'Litchi' in the same post) Does any autonomous flight program allow one to land back on Home Point like RTH?
 
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I use Litchi rather than Ultimate or DJI go. I have never had a issue with it's planned flights or operation. My P3A has always done what was asked and always comes back to "Daddy". I imagine the references to "lost" or other issues were not from Litchis corner. Knowing what settings have to be set to, and being familiar with the Phantom, from my experience of over 400 air miles flown with Litchi, you should not have a problem using it.
 

Mark The Droner

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I've always thought that GPS fixes are not the same up high in the air as they are down on the ground. Why? Because the angles of the satellites are slightly different. Seems to me if you have a dozen sats to the west and only three to the right, the GPS fix is not going to be perfectly perpendicular to the surface of the earth as you gain altitude because the angles will change and the fix will be skewed relative to altitude.

But I've been told I'm mistaken and fixes are perfectly perpendicular to the surface of the earth regardless of altitude.

But if I was right, that might be an explanation. The way point is made up above, and then it autolands straight down, period.

OTOH, an RTH seems to sometimes hover way overhead above the home point but not be directly overhead, and then it will adjust as it lowers itself, coming down at a very slight angle so that it's closer to the home point when it lands.
 
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I've always thought that GPS fixes are not the same up high in the air as they are down on the ground. Why? Because the angles of the satellites are slightly different. Seems to me if you have a dozen sats to the west and only three to the right, the GPS fix is not going to be perfectly perpendicular to the surface of the earth as you gain altitude because the angles will change and the fix will be skewed relative to altitude.

But I've been told I'm mistaken and fixes are perfectly perpendicular to the surface of the earth regardless of altitude.

But if I was right, that might be an explanation. The way point is made up above, and then it autolands straight down, period.

OTOH, an RTH seems to sometimes hover way overhead above the home point but not be directly overhead, and then it will adjust as it lowers itself, coming down at a very slight angle so that it's closer to the home point when it lands.
Yeah that is something to think about. OTOH the GPSs in the car, boat, real airplane and my stupidphone are probably not any more accurate than the accuracy I am complaining about with the Phantom. I just wonder how it sticks the landing when it is doing RTH.
 
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I use Litchi rather than Ultimate or DJI go. I have never had a issue with it's planned flights or operation. My P3A has always done what was asked and always comes back to "Daddy". I imagine the references to "lost" or other issues were not from Litchis corner. Knowing what settings have to be set to, and being familiar with the Phantom, from my experience of over 400 air miles flown with Litchi, you should not have a problem using it.
Thanks Gramm. I have reinstalled Litchi on a Samsung tablet and plan on trying it tomorrow. Not one to take unneeded chances I have Litchi on a tablet without any other DJI program. Litchi will operate alone won't it? IE: it does not need DJI Go as in being an overlay or something does it?
 
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No, it needs nothing except your Phantom to fully open up the box 'o fun. Make sure of all the settings, RTH alt, ect.
 
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No, it needs nothing except your Phantom to fully open up the box 'o fun. Make sure of all the settings, RTH alt, ect.
OK Great Thanks mucho. I had bought Litchi months ago, and read the documentation but that was a while back. If memory serves, it is very similar to UF. I had trouble getting it to run on something, I think Samsung before, and just jetisoned it because the seller was NO HELP at all. But I had already paid for it, so there was not much I could do, and the fanboys here flame you if you even suggest there might be a tiny flaw in Litch.
 
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Try it with the device you use, and post here with any issues. Researching would usually clear up any problems using devices. I use both Nvidia shield and Samsung G5 with no faults.
 
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Try it with the device you use, and post here with any issues. Researching would usually clear up any problems using devices. I use both Nvidia shield and Samsung G5 with no faults.
Thanks. I have a Note4, an LG G stylo and a couple of Samsung tablets, I will find one that will work I am sure. I remember it would not connect before, even going through all the 'USB debugging on/off, MTP device, etc.

Thanks again.
 
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I have read that sequence of powering on drone,device is important. Think it was drone first, then controller, then device.
 
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I have read that sequence of powering on drone,device is important. Think it was drone first, then controller, then device.
OK Here we go."Cannot connect to DJI servers to verify the app" . This is the numbskull crap that sends me over the edge. The Tablet has a 95 M wifi connection and brings up google earth with my location on it, so there is an internet connection, but Litchi suggests I find another way to connect. It is an LTE tablet too. AAArggh!
 
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OK Here we go."Cannot connect to DJI servers to verify the app" . This is the numbskull crap that sends me over the edge. The Tablet has a 95 M wifi connection and brings up google earth with my location on it, so there is an internet connection, but Litchi suggests I find another way to connect. It is an LTE tablet too. AAArggh!
Try clearing the data cache from both apps clear the cache from the tablet reboot tablet try again
 
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Try clearing the data cache from both apps clear the cache from the tablet reboot tablet try again
Also remove default app from opening so you have a choice each time the choice menu will pop up pick: only once
 
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Also remove default app from opening so you have a choice each time the choice menu will pop up pick: only once
, you may also have to check the permissions in both apps to allow Internet contact Network contact
 
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, you may also have to check the permissions in both apps to allow Internet contact Network contact
YUP uninstalled DJI Go, cleared data and defaults uninstalled and reinstalled Litchi, checked permissions, full internet/network access, bird blinking green and camera able to move up and down, WiFi signal good, connected as MTU device rather than camera. I think I am beginning to see that I am pretty safe from losing my little bird with Litchi.
 
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YUP uninstalled DJI Go, cleared data and defaults uninstalled and reinstalled Litchi, checked permissions, full internet/network access, bird blinking green and camera able to move up and down, WiFi signal good, connected as MTU device rather than camera. I think I am beginning to see that I am pretty safe from losing my little bird with Litchi.
You would think....with this many people having this same problem with this same product they might just maybe have a manual workaround. Just tell us which file to edit or something.
 
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YUP uninstalled DJI Go, cleared data and defaults uninstalled and reinstalled Litchi, checked permissions, full internet/network access, bird blinking green and camera able to move up and down, WiFi signal good, connected as MTU device rather than camera. I think I am beginning to see that I am pretty safe from losing my little bird with Litchi.
"Excellent"! (George Burns voice from the 'Simpsons'
 
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let me share my experience using litchi.
may be more than 10 times i use it for waypoint, but most of them i set high altitude (about 50meters) and worked just fine, so on the perspective of the camera, there will be no different if it was actually missed a few meters due to GPS accuracy.

but last week, i planed the misson to have some low altitude points below 10meters. and i found it fly few meters away from it should be by the path i've draw on the litchihub and almost hit the street light stand, that was very close. i'm not sure wether this experience is something related to your issue or not...

then after that day, my friend told me to check the GPS accuracy setting inside the Aircraft sub menu, the default value is 15meters. but i have not try it yet due to my work days....

may be you can check that setting and try to fly again with litchi waypoints, and see will it make some differences....

Sent from my SCL23 using PhantomPilots mobile app
 

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