Drone drifts in loiter mode

Hi! My drone seems to drift a lot in loiter mode. I have uploaded my logs here: https://drive.google.com/open?id=1YDKJeyPzPX1SeyNvbe8mRlmZ_YA2A0v2

Any ideas what may going on? Thanks!!

Your not waiting long enough for the GPS to settle.
Just because it says 3D fix does not mean the EKF is happy with the velocity variance.

Power the copter up and let it sit until you get a 3D fix
Before arming switch to loiter mode to check that all is well, if not you will get a rejection tone and LED
When the copter gives a confirmation tone and Green LED
Switch back to Stab or anything and fly as normal.

See how go doing that procedure and let us know please.

I tried that and while it is better, the drone still drifts a bit

Please send log file of this flight

Yes, Please send a log file.
How much is a bit? In the 10 seconds of loiter time the copter floats just under your GPS accuracy.
For better results you may want to think about a range finder or RTK.

You are also flying very low and not above ground effects.

Here is the latest log: https://drive.google.com/open?id=1vitY_CuWGpb1bsJBohvVtiP4yKel-EF_

How high do I need to be?

How can I find how much is a bit? Will it be in this log file: https://drive.google.com/open?id=1vitY_CuWGpb1bsJBohvVtiP4yKel-EF_

Sorry, I’m very new to this

Sorry I should have Ask, How much does it drift?

This log is high enough. I see some movement but less than GPS accuracy.
How much is it drifting?

yes i just want to confirm that every thing seems ok in your log.
could you send a video of copter flying?

Hey, sorry for the late response. It’s kind of weird in the way that it doesn’t drift and then suddenly it will move like a couple feet and then come back to it’s original spot. Could this be fixed or is it just a limitation of the GPS?
When it moves, the odd thing is that it isn’t because of the wind either.

Unfortunately, I just moved into college and don’t have my copter with me. I’ll be back on the weekend when I’ll be able to fly and I’ll send a video then! Thanks!

Sounds like the drift is about the same as GPS accuracy. There are better GPS, of course at a cost.
A second RTK GPS or range finder helps. Nothing is perfect even at 1CM reported accuracy its not going to hover exact.

Any suggestions for a reasonably priced RTK GPS or range finder? Thanks!

This is what I use today. This receiver cost with case is $250 each and perform excellent (not perfect).
The antennas on this link are fine for a base station but not for rovers, they are too heavy!
The ANN-MB antenna is recommended.
I am waiting on the HerePro with full FC capabilities. I here December is a fair estimate for release of beta units.
There are some other F9P with integrated compass and antennas but I do not have a link.
If these are out of your price range look through the ublox site for M8P Receivers.


Thanks! Unfortunately this is really out of my price range haha. I was thinking I may be able to find something under $50, but I guess it isn’t worth it. Thanks though!

Even with a M8N if you mount it up and away from your electronics you should get very precise loiter and althold. My 180mm mini quad with a micro M8N mounted right above the camera still only drifts a foot or so.

From this image: https://drive.google.com/open?id=1FhzN94fs0jM8fEpenej3aE8T0yfOoWb7

Does it look like my GPS is high enough? Or should I bring it higher? Thanks!