Mavic compass needs to be calibrated before each flight

[BudWalker]

And further proof today with another large move and another prompt for compass calibration.

So, it arrives from china (long way). Demands calibration. Flies for 2 weeks within roughly 30 mile radius with no calibration prompts.

Its then moved 7,000 miles, starts up, demands calibration. Then does a further 5 flights within 20 mile radius with no issue.

Then its moved 700 miles. Demands calibration. 4 more flights within 4 mile radius all fine.

Moved 1100 miles today, demands calibration. Further flights in the area no issue.

Also interesting to note that initially in Opti mode it doesn't ask for it but as soon as it gets a GPS lock it goes to "check app" and demands a calibration so im fairly sure its detecting its moved a long way and forcing one.

It's not a stupid idea because despite what the compass expert claims above, compasses do need re calibrating when moved to various geographical areas. Depending exactly how they're implemented it can vary but lots do. I see it all the time with non drone based compasses.
I guess DJI have changed the compass implementation and have implemented a software nag to get people to do it when its moved.

It'll be travelling a further 250 miles tomorrow. Will be interesting to see if it wants it again or not.

Can you provide the .DAT for one of these flights where the compass calibration is required after moving a large distance? I'm thinking there may be some relationship to what was posted here.
Mavic 2 wants a compass calibration 30 days after last one

Look here or here to see how to retrieve a .DAT.

 

[Meta4]

I was surprised as it seems that’s all I am reading lately is how so many drones are asking for a gps tuneup .

GPS tuneup?
The compass is completely separate from and unrelated to the GPS system.
There's nothing you can do to calibrate or tune up the GPS.

 

[Chopstix Kid]

It's not in the firmware, because mine has never asked to be calibrated - not after arriving from China and not after moving around within the US.

It would probably help the discussion here if, rather than just asserting that compasses need to be recalibrated after moving, you could explain why and how they are recalibrated. That might shed some light on where that idea comes from.

As soon as I unboxed mind and powered it up, both the IMU and Compass were is an error state. I power cycled it to make sure, same errors. Recalibration and errors went away.

As @Meta4 stated, Compass calibration helps the aircraft discern the difference between it’s own magnetic field and that of the earth—Fair. I would suggest the theory that changes in the earths magnetic field realized by significant change in the distance could render the aircraft to no longer discern the difference. Just my 2 cents.

 

[Meta4]

As @Meta4 stated, Compass calibration helps the aircraft discern the difference between it’s own magnetic field and that of the earth—Fair. I would suggest the theory that changes in the earths magnetic field realized by significant change in the distance could render the aircraft to no longer discern the difference. Just my 2 cents.

Callibration helps the Mavic to identify which magnetic fields belong to the drone so they can be ignored.
These are the magnetic influences that rotate with the Mavic while it's being calibrated.
Unless the drone is modified, they should stay the same and not vary with distance from anywhere.

 

[Meta4]

So the theory that the new Mavic 2s will now ask you to calibrate the compass if it moves ~30 miles does make some sense based on my experience last Saturday.

Once you have a hypothesis, the next step is to test it.
Some basic questions to investigate might include:
Do you observe the same conditions every time you travel 30 miles?
Is it only for east/west movement or is direction irrelevant?
Are all other Mavics exhibiting the same issue?

 

[sar104]

As soon as I unboxed mind and powered it up, both the IMU and Compass were is an error state. I power cycled it to make sure, same errors. Recalibration and errors went away.

As @Meta4 stated, Compass calibration helps the aircraft discern the difference between it’s own magnetic field and that of the earth—Fair. I would suggest the theory that changes in the earths magnetic field realized by significant change in the distance could render the aircraft to no longer discern the difference. Just my 2 cents.

Please read post #25.

 

[gnirtS]

All I can see there is proof that you don't understand what compass calibration does and just want to stick with your assumptions despite the facts.

Generally when the drone says "Calibration required" that means it wants it calibrated. Thats a fair amount of evidence right there.
Believe it or not, people are trained to be able to read from a fairly early age. A benefit of this is when the drone and app tells them something they can both read and understand.
The drone prompts to recalibrate when its moved long distances. Its as easy as that. Not sure how to simplify that further for you.
Whether you like it or not, its doing that.

 

[gnirtS]

It's not in the firmware, because mine has never asked to be calibrated - not after arriving from China and not after moving around within the US.
.

So far i know 3 x other M2P users. All needed a calibration after initial arriving.
In addition to mine, 2 of others have moved the drone above 1000 miles in one journey and both of theirs prompted to recalibrate as a result.

Im fairly sure its going some geographical checking as the initial Opti startup doesnt trigger it and only after its got a GPS lock.

 

[gnirtS]

Can you provide the .DAT for one of these flights where the compass calibration is required after moving a large distance? I'm thinking there may be some relationship to what was posted here.
Mavic 2 wants a compass calibration 30 days after last one

Look here or here to see how to retrieve a .DAT.

I'll give the DATs but it'll be in 2-3 weeks time roughly. Internet in the jungle isn't any more than the occasional 2G modem speed rate.
By that time it would have done a few more multi thousand mile jumps.

 

[Chopstix Kid]

Callibration helps the Mavic to identify which magnetic fields belong to the drone so they can be ignored.
These are the magnetic influences that rotate with the Mavic while it's being calibrated.
Unless the drone is modified, they should stay the same and not vary with distance from anywhere.

Gotcha... that makes more sense when you state it like that. Quite frankly, I think the term itself is what is creating all the confusion since compasses, in general, do require recalibration.

So now this goes back to my initial post back on page 1 in that perhaps there is a defective compass (or supporting component) if it is continually throwing an error that requires recalibration.

Is however, quite feasible that a shift in magnetic fields by a geography change could in fact confuse the aircraft depending on how drastic of a change there is. That is why some people report no issues while others such as @gnirtS is prompted to calibrate with significant change in distance. I can attest that every drone I have purchased has required a recalibration as soon as I turned it on the first time.

 

[Fplvert]

Generally when the drone says "Calibration required" that means it wants it calibrated. Thats a fair amount of evidence right there.
Believe it or not, people are trained to be able to read from a fairly early age. A benefit of this is when the drone and app tells them something they can both read and understand.
The drone prompts to recalibrate when its moved long distances. Its as easy as that. Not sure how to simplify that further for you.
Whether you like it or not, its doing that.

Manual Camera Controls - Am I Missing Something?

 

[Meta4]

Generally when the drone says "Calibration required" that means it wants it calibrated. Thats a fair amount of evidence right there.
Believe it or not, people are trained to be able to read from a fairly early age. A benefit of this is when the drone and app tells them something they can both read and understand.
The drone prompts to recalibrate when its moved long distances. Its as easy as that. Not sure how to simplify that further for you.
Whether you like it or not, its doing that.

If you understood what calibration of the compass does, you'd also understand that it makes no sense for calibration to be required due to moving some distance.
There's something else happening here.

 

[gnirtS]

I fully understand how they work and use them for non drone in daily life.

We have 2 simple facts here - the DJI manual states calibrate if moving over 30 miles or unused for 30 days and (ii) the drone appears to be knowing its moved a significant distance (probably via gps) and is prompting a calibration. You can deny it all you want but thats whats happening. See also the calibration after 30 days thread with someone getting that from the .dat file.

It looks like they've changed how it works and the checks it does to fit in with the new manual revisions.

(or are you also claiming DJI themselves and the engineers are unaware how their own compass works despite building it?)

 

[Fplvert]

If you understood what calibration of the compass does, you'd also understand that it makes no sense for calibration to be required due to moving some distance.
There's something else happening here.

Yes, I think you figured it out. Carry on!

 

[Chopstix Kid]

Magnetic interference will trigger it was well.

 

[DanMan32]

Mine never asked for compass calibration even when first turned on. It does generate mag interference when turned on while legs folded.

My phone and tablet with built-in compasses need the figure 8 calibration all the time so it stands to reason the M2 may also be prone to the same sensitivity. Why some of us get it and others don't is a mystery.
Also strange the M2 only has one compass.

All this academics on how calibration works (or thought to work) on an M2 is bogus unless you were one of the DJI engineers who designed it or reverse engineered the hardware and firmware on the M2. If not, you're guessing. An educated guess no doubt but still a guess. There very well could be code in the firmware to request calibration when moving more than 30 miles. It could be a requirement in specific directions. IOW might not be asked for moving north but asked for moving west.

 

[Goof]

Is the em field around the antennas enough to cause a significant disruption? Could this change depending on what radio channel you're on / how much local radio interference there is in the area?

 

[WithTheBirds]

I believe none of the above two cases are really valid here. 3-4 different people with previous experience of Mavic 1 have confirmed that their M2 is much more sensitive with its compass and asks frequently for re-calibration when moved a few miles/Km from its previous location.

It can't just be a magnetic interference of a location because previous Mavic1 didn't have this issue. Also, I assume we all know how to use GO4 app.

You know what assumption is- the mother or all, lest say, unexpected disasters...

 

[WithTheBirds]

The Mavic 2 compass seems it might be more sensitive to interference than the phantoms. I haven’t needed to recalibrate them though. My suspicion is the small size and how quiet it is has me launching from places I wouldn’t take the phantom, more reinforced concrete and other suspects around. I have got around the problem by moving.

 

[lmel2005]

If new Mavics request compass calibration, more often than other DJI drones (or before every flight), then there is an issue.

This issue may be hardware and/or software related.