Little anomaly with finishing waypoint missions

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
Oh OK Thanks. I have never tried the GPS accuracy menu and do not recall seeing it. I will try it today. But apparently not with Litchi.

On the same tablet, with the same drone, with the same cable DJI Go and Ultimate flight connect without a hiccup, Litchi. Are you listening?
 
  • Like
Reactions: sinxa
Note that the gps system spec for the system being used for the Phantoms is specified to an accuracy of +- 16 feet 95% of the time. Mostly I see errors ranging between 6-12 feet, but you cannot plan on better than 16 feet.


Sent from my iPad using PhantomPilots
 
  • Like
Reactions: Loz
Oh OK Thanks. I have never tried the GPS accuracy menu and do not recall seeing it. I will try it today. But apparently not with Litchi.

On the same tablet, with the same drone, with the same cable DJI Go and Ultimate flight connect without a hiccup, Litchi. Are you listening?
Might want to read this : Litchi + DJI GO + Samsung Tab S2 Problem
Or search Google (your device model)+not connecting to litchi. Seems it's not Litchi at fault, but the operating system programmers changing the way the devices connect by way of default apps, or usb methods. I am thinking if you follow the procedures taken by the users on that thread I listed you may find a solution. Don't give up on Litchi just yet. Clearing the default app data and using power up and connecting methods seem to be the answer of a lot of users.
 
As far as the GPS accuracy , Careful planning and a finger on P toggle is always best. A higher altitude will usually have more satellites to lock onto giving a better positioning fix. Lower altitudes, lower satellite locks will have a loser positioning fix. All in all, the phantom is a exellent machine, engineered well past what I had as a kid ( I played with sticks and rocks and Brontosaurus pups) Here is my "Light pole" experience showing GPS a little off planned mission. All ended well, but remember to plan on mishaps and know how to respond:
To view this content we will need your consent to set third party cookies.
For more detailed information, see our cookies page.
 
As far as the GPS accuracy , Careful planning and a finger on P toggle is always best. A higher altitude will usually have more satellites to lock onto giving a better positioning fix. Lower altitudes, lower satellite locks will have a loser positioning fix. All in all, the phantom is a exellent machine, engineered well past what I had as a kid ( I played with sticks and rocks and Brontosaurus pups) Here is my "Light pole" experience showing GPS a little off planned mission. All ended well, but remember to plan on mishaps and know how to respond:
To view this content we will need your consent to set third party cookies.
For more detailed information, see our cookies page.
Yeah thanks, good advice. I am pretty careful and when it thought the house or car, etc. were good landing spots I simply hit the 'up' stick to get some comfortable altitude, then steered onto a less obstructed area. I had envisioned it accomplishing the whole enchilada alone from motor start to shutdown. Remember for me this thing is just a toy. The other toys which have spark plugs are capable of getting into M U C H more trouble than a flying Kodak.
 
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?
OK everyone, thanks for your help. I did a test this morning and figured it out. In my missions I had a beginning waypoint at the takeoff point and an ending waypoint exactly on top of it, or withing a few feet. I have not discovered the mechanism which is in play, but that causes the last (Landing) waypoint to be inaccurate. I simply deleted the first unnecessary waypoint and the bird nailed the landing like a gymnist. I actually do not remember my reasoning for an unused waypoint to begin with, except maybe to cause the bird to get to altitude before it left. But it apparently was the problem. I read, or one of you posted, to not have 'duplicate' waypoints. Good advice.
 
  • Like
Reactions: Loz
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
OK I have searched the aircraft user manual 10 times and find no mention of a GPS accuracy setting. I have not fired up the drone and rooted around in the menus for it yet, as I prefer to read about it rather than just go changing things. Can you tell me where this is?
 
It isn't a DJI issue. The GPS system available to all drones is run by the US government and has an accuracy spec of +- 16 feet, 95% of the time. This same spec is applicable to boats, hikers etc. There is no magic bullet to get around this. Systems can reduce the inaccuracy by taking multiple readings and averaging them, but to take enough with affordable light weight hardware takes too much time for real time control of the aircraft.

Boats and hikers move much more slowly, and can afford the delays caused by averaging multiple samples.



Sent from my iPad using PhantomPilots
 
It isn't a DJI issue. The GPS system available to all drones is run by the US government and has an accuracy spec of +- 16 feet, 95% of the time. This same spec is applicable to boats, hikers etc. There is no magic bullet to get around this. Systems can reduce the inaccuracy by taking multiple readings and averaging them, but to take enough with affordable light weight hardware takes too much time for real time control of the aircraft.

Boats and hikers move much more slowly, and can afford the delays caused by averaging multiple samples.



Sent from my iPad using PhantomPilots
If I may quote myself just above your comment:

"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."

and then I wrote:

"OK everyone, thanks for your help. I did a test this morning and figured it out.
In my missions I had a beginning waypoint at the takeoff point and an ending
waypoint exactly on top of it, or withing a few feet. I have not discovered
the mechanism which is in play, but that causes the last (Landing) waypoint
to be inaccurate. I simply deleted the first unnecessary waypoint and the
bird nailed the landing like a gymnist. I actually do not remember my reasoning
for an unused waypoint to begin with, except maybe to cause the bird to get to
altitude before it left. But it apparently was the problem. I read, or one of
you posted, to not have 'duplicate' waypoints. Good advice."

So are you one of those who just posts out of boredom?
 
Perhaps you should read your own post before making snarky comments.

"OK I have searched the aircraft user manual 10 times and find no mention of a GPS accuracy setting. I have not fired up the drone and rooted around in the menus for it yet, as I prefer to read about it rather than just go changing things. Can you tell me where this is?" - your words. Remind me to not make any efforts to help you in the future.

"So are you one of those who just posts out of boredom?"
 

Members online

No members online now.

Forum statistics

Threads
143,066
Messages
1,467,358
Members
104,936
Latest member
hirehackers