Having trouble calibrating the compass

[Britishbigfoot]

I've had a good read, am stood miles from any metals, the controller, other objects, in an open field that is just mud. I'm wearing zero metal - I'd be naked if I tried any harder!

I've successfully calibrated several P4P's, an Inspire 1, a Mavic Pro all in this exact spot.

The P3S just refuses to calibrate. Over and over I've done it. I've just watched this video

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and would like to know if anyone here has done this with any luck. The thing is with this method is the number of variables to isolate the issue, is it the magnet? The reinstall of Go? Beats me, which is why I'm reaching out.

I'm handy, and good with electronics, but I'd rather not have to attempt this:

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I figure it's this part I need:
DJI Phantom 3 Compass Part 11

But I don't want to spend £49 on a tiny gizmo. Advice welcome!

 

[RodPad]

What are the values on the compass screen?
You can see them if your going to do a IMU calibration.
If they are all zero you won't be able to calibrate the compass.

Rod

 

[RodPad]

Advanced - Compass Mod Value

This one looks good.
Ideal compass value

Another
Compass Calibration: What is measured?

Rod

 

[Meta4]

The P3S just refuses to calibrate. Over and over I've done it.

There are two possible causes for a compass that won't calibrate.
1. Your Phantom is very close to steel ... like on a reinforced concrete surface.
2. The fine wires to the compass sensor are broken or the compass is disconnected
Check your compass sensor data in the app. If it has zero for the compass you have condition 2.

I've successfully calibrated several P4P's, an Inspire 1, a Mavic Pro all in this exact spot.

There's no need to recalibrate the compass of a P4 pro (see the manual p57)

 

[Britishbigfoot]

Thanks all. I'm out later and I'll look at the compass values (slipped my mind that I could).

 

[Britishbigfoot]

Hi all, I sorted it. I just left it for on 30 minutes in a field with nothing nearby. No props on to avoid any issues!

IT'S ALIVEEEE!!!

And mighty fun to fly! Love playing in ATTI.

 

[Britishbigfoot]

To clarify: the IMU likely needed to warm up. The GPS fix was probably goosed as I'd traveled 100 miles+ from the last location it had a fix (it needed to re-download GPS almanac data but I didn't realize)

This was evidently affecting the compass calibration.

GPS systems explained

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To clarify; I tried reinstalling GO, no dice, made no difference.

I tried leaving the battery out for 18+ hours to discharge any circuits, made no difference.

Patience was the solution

(Thanks to Lee, if you ever read this mate!)

 

[Meta4]

To clarify: the IMU likely needed to warm up. The GPS fix was probably goosed as I'd traveled 100 miles+ from the last location it had a fix (it needed to re-download GPS almanac data but I didn't realize)
This was evidently affecting the compass calibration.

GPS and IMU shouldn't make any difference at all as they are separate and unrelated to the compass which is an independent system.

 

[RodPad]

Glad you got it working.

You said you left it on for 30 min.

What is unanswered,
Did you do a compass calibration?
Did you look at the compass values? Before or after?
Did you do a IMU calibration, or run a check?

The compass is not going to be effected by where the last time the Phantom had a lock on satellites, even if it did it only takes my 1989 Garmin Map12 in a clear sky 2 min to identify its position and direction of travel. That is with 3 satellites and it can track up to 12.

Let us know if you have more issues come about, GPS, IMU warming up, I can't see the connection.

Rod

 

[Britishbigfoot]

Glad you got it working.

You said you left it on for 30 min.

What is unanswered,
Did you do a compass calibration?
Did you look at the compass values? Before or after?
Did you do a IMU calibration, or run a check?

The compass is not going to be effected by where the last time the Phantom had a lock on satellites, even if it did it only takes my 1989 Garmin Map12 in a clear sky 2 min to identify its position and direction of travel. That is with 3 satellites and it can track up to 12.

Let us know if you have more issues come about, GPS, IMU warming up, I can't see the connection.

Rod

Hiya, sorry, been slammed!

I left it a while in the field yes, and the IMU was normal, the compass values read normally (IIRC) and I didn't do a calibration. I'm about to test it again (for the first time since the 2nd July) and I'll let you know on all these points as a second run.

Whatever I did or did inadvertently, it helped! Thanks for the support Rod!

 

[RodPad]

Thanks, we all need closure.

Rod