Naza GPS - Slight back/left drift before solid hover

[halfpress]

I'm quite sure I have my GPS module installed, aligned and properly configured with offsets in the Naza.

This is on my F550 with it sitting dead center on the back of the top plate using the stock mast. The red arrow points right down the middle to the front (eyeballed it with a laser level line). My offsets account for the 10cm mast height and what looks to me like about a -7cm Z offset to be on the back of the top plate relative to the middle of the Naza itself.

When flying in GPS mode, when I stop movement to hover, it almost always drifts to my left (if I am facing the BACK of the F550) and backwards a decent number of feet before settling into a pretty solid hover. Rotated 180 degrees to face me, I get the expected opposite of it drifting away from me and to my right some feet before the hover stabilizes.

It doesn't seem consistent, though, because at times it seems to settle in just fine as soon as I stop moving.

Any thoughts on whether this is a problem in my configuration, F550 or even possibly a location-induced issue? I will test it more flying in another location for comparison.

Thanks!
- Aaron

 

[tstrike]

Depending on where in the world you live, you'll have to rotate the gps puck's arrow a little to the left or a little to the right, it has to do with "magnetic declination" and the world being a round ball instead of a flat map or some such poppeycock. Remember, your gps numbers reflect center of gravity on your hex, find that spot and measure your pod again see if the numbers in naza assist jive.

 

[halfpress]

Depending on where in the world you live, you'll have to rotate the gps puck's arrow a little to the left or a little to the right, it has to do with "magnetic declination" and the world being a round ball instead of a flat map or some such poppeycock. Remember, your gps numbers reflect center of gravity on your hex, find that spot and measure your pod again see if the numbers in naza assist jive.

Thanks! I will certainly try some adjustments and also be doubly sure my offsets are correct.

To confirm one thing: the drift I'm describing is not constantly to the back and left. It always settles to a nice hover, so it's not like some people describe where it drifts constantly like there is stick being applied in some direction. Once it has done its little drift, the hover gets steady. Attitude mode holds just fine if I'm not fighting the wind (a rare thing around here this winter/spring, apparently... dammit). You feel these adjustments apply in this case, too, since I don't think I'm seeing the full on toilet bowl effect some describe?

Thanks!
- Aaron

 

[Benjamin Kenobi]

That's normal. The GPS is only accurate to within a meter or so. I forget the exact figures. It's still pretty good though eh?

 

[halfpress]

That's normal. The GPS is only accurate to within a meter or so. I forget the exact figures. It's still pretty good though eh?

Absolutely! But it just stands out to me that it drifts off so many feet before hovering when the Phantom I had (based on the same Naza/GPS) seemed to stop pretty well dead with phenomenal reliability. I don't recall it doing anything this pronounced.

Thanks!
- Aaron

 

[deathroFPV]

Mine does drift too. Before I fly I check to see if she will hover in place. If not I land and reboot (unplug wait a few seconds the plug back in). That fixes my drift issue and I hope that helps you.

 

[Eggbeater]

Have you tired to shift some weight in the opposite or same direction of the drift? (without changing the XYZ software) My two 6s bricks were positioned dead centered (fore/aft, L/R) under the bottom plate but just the offset weight of the connection harness forced me to shift batteries off center to get a better CG. Try it and let me know.

 

[halfpress]

Mine does drift too. Before I fly I check to see if she will hover in place. If not I land and reboot (unplug wait a few seconds the plug back in). That fixes my drift issue and I hope that helps you.

I will give this a whirl. It does seem to stop drifting during a flying session, but I need to pay closer attention to whether it corrects just after several minutes or between landings/resets.

Thanks!
- Aaron

 

[halfpress]

I've not tried shifting weight, no. I'm adding some DIY landing legs later today along with my camera gimbal and GoPro, so I'm going to need to readjust everything from voltage warnings to probably the compass settings again today. Once the dust settles, I'll see where I'm ending up in terms of hovering behavior and tweak accordingly.

Thanks!
- Aaron

 

[dg2010]

My Naza drifts. More the first time I enable GPS, the second time it tends to be rock solid depending on my GPS link.

 

[deathroFPV]

No problem Aaron,

Let us know how you fixed it as soon as you find out. good luck

 

[Eggbeater]

There' sometimes so much we want to do that we can't stop to do a controlled experiment (only change one variable at a time) and get a handle on an issue. I can relate. Besides the rebooting and shifting weight ideas I will throw in something that may or may not be related.

Using a NAZA-H (not M) for the first time, I got in a pinch due to a mostly left cyclic that was sudden and unexpected on a large helicopter. It began only when I switched to ATT Mode. During a lot of discussion and no real answer, DJI instructed a friend to not use ATT. Mode (only manual and GPS) until a fix could be completed. Soon afterwards, they came out with an added feature to the Assistant which allowed us to trim this tendency out. I haven't used it yet and don;t know how well it works. But there could be sopme connection between the M & W versions and what some are seeing.

So this is not directly related but goes to show you that we can try our best and the answer may still be beyond our powers as consumers. In the "old days", we would not roll out new technology until we tested it. That reliability and integrity was what you were buying too. Today, in the mad rush to get it out there and make a couple bucks before someone clones it, the consumer does way too much of the R&D. Wouldn't it be nice to not doubt the hardware and software and concentrate on what WE did wrong?

 

[pspero]

I am noticing that when I am flying my quad in GPS mode and I let go of the controls to hover, my quad slowly flies in about a 10 or 12 foot circle facing the same direction. I then fly it to a new position, stop and hold, and the same thing happens. I was wondering if you guys could give me your thoughts on this.


Here is my current build - TurboAce X830-D quad, Devo10TX, DJI NAZA-M flight controller, GPS, Telemetry,35A ESC,BL Motors, 5300M+TX Batt, 12” props., (FPV - Immersion 600MW 5.8 Ghz AV TX, Immersion 600MW 5.8 Ghz AV RX, 5.8 GHZ SpiroNET Omni Antennas, Fatshark Dominator Goggles, FPV camera 600TVL Sony Super HAD CCD)

 

[deathroFPV]

I am noticing that when I am flying my quad in GPS mode and I let go of the controls to hover, my quad slowly flies in about a 10 or 12 foot circle facing the same direction. I then fly it to a new position, stop and hold, and the same thing happens. I was wondering if you guys could give me your thoughts on this.


Here is my current build - TurboAce X830-D quad, Devo10TX, DJI NAZA-M flight controller, GPS, Telemetry,35A ESC,BL Motors, 5300M+TX Batt, 12” props., (FPV - Immersion 600MW 5.8 Ghz AV TX, Immersion 600MW 5.8 Ghz AV RX, 5.8 GHZ SpiroNET Omni Antennas, Fatshark Dominator Goggles, FPV camera 600TVL Sony Super HAD CCD)

Check your magnetic declination and make sure it is set to your flying location. Also make sure your gps location is correct in the naza assistance program. After all that recalibrate gps and hopefully it goes away. Also try to reboot is still drifting. let me know if that helps.

 

[pspero]

Thanks for the advice, I checked my magnetic declination, to be honest, I didn't even know what that was until now, but now I do. The reboot did the trick. I did launch and go through the gps calibration software, a good learning experience. Thanks again for your advice.

 

[halfpress]

Just so I understand, what kind of "reboot" are you all discussing? If drifting, land it, reset power and immediately try again? Or are you using the term "reboot" to mean a

 

[David Lee]

Is the magnetic declination in the setup software or just moving the GPS receiver on the multirotor? Thanks in advance!

Dave

 

[pspero]

By reboot, I do mean power off and power on. At the end of my last flight where I noticed the drifting in GPS mode I did a power off, on my next flight today, I did a power on and did not notice the drifting.

 

[deathroFPV]

Thanks for the advice, I checked my magnetic declination, to be honest, I didn't even know what that was until now, but now I do. The reboot did the trick. I did launch and go through the gps calibration software, a good learning experience. Thanks again for your advice.

Glad it worked out for you. I bet it make you feel more confident when flying. I actually got that tip while visiting Kloner at his house when he helped me with my TBS Discovery issues.

 

[deathroFPV]

Is the magnetic declination in the setup software or just moving the GPS receiver on the multirotor? Thanks in advance!

Dave

It's actually how you position the gps arrow. Not in the software. You know you need to check it when your quad doesn't fly strait, toilet bowl affect (quad goes in circles) and drifting.