Watch exactly does Compass Interference measure?

[iBallesty]

apologies : Title should read "WHAT exactly does the Compass Interference measure?" (Dyslexics lure KO)

hi

as a newbie I assumed that the compass interference (Main Controller settings --> Advanced Settings --> Sensors --> Compass) would be the same in a single location independent of orientation. It appears I am wrong.
I can go to a spot far from any metallic (or other interference; I wear no watch; I am on a wilderness hillside; controller far away; etc.). The initial compass interference is green, but turns to serious red when in a particular orientation. Why is this?
Does this happen to everyone?

Surely compass interference is a measure of interference in a specific location.

Attached a link to a video of it happening

Hope you can enlighten me.

Iain
App 4.3.0
Aircraft 01.00.0400
Precise fly DB for both 01.00.01.09
Basic Fly safe DB 01.00.01.07

 

[lollip]

Following, I'm curious about the answer...

 

[WartexxNL]

Followww

 

[Top Hat]

Is it "what" or you want us to "watch"?

 

[MAIRMPRO]

I'm interested in answers to this question as well. My interest is because I have not been able to fly my Mavic Air outside of the United States, two different locations (South America and Micronesia), because it will not calibrate compass on these foreign locations. It does calibrate immediately and on first try when back in the United States. It does not have anything to do with watches, distance from controller, as those were the same on all locations. By the way, my Mavic Pro has no such problems on these very same foreign locations.

 

[Kilrah]

As far as we know it looks at how far the absolute value of the magnetic field is from what it was during the last calibration.

 

[MAIRMPRO]

As far as we know it looks at how far the absolute value of the magnetic field is from what it was during the last calibration.

Thanks!
Therefore, can one conclude that geographic location matters? Because it won't calibrate compass after many attempts when taking it thousands of miles away.
If so, is there a way to re-set the Mavic Air when moving to radically different locations? So it circumvents it being tied up with the last calibration process?
Why does it work with the Mavic Pro and not the Mavic Air? (I've taken the Mavic Pro to the same locations, and it has no problems).
Thanks again.

 

[Kilrah]

It does vary by location obviously but should have no effect at all on the ability to calibrate. The whole point of the calibration is to forget whatever conditions were stored before and start fresh.

 

[MAIRMPRO]

Well... my Mavic Air NEVER calibrated on two trips I've made overseas. And calibrated quickly and normally when back to the USA. The mystery continues... and no one from DJI ever offered an answer.

 

[Air Beetle]

Did you calibrate it correctly? I was curious about some people have the compass point 180 out. I did a compass calibration intentionally wrong (Air in the wrong plane on second step) and I could get 180 out and 90 out. It seems like DJI should check that you have it on the correct side and spin it hte correct direction.

 

[MAIRMPRO]

Let me re-phrase this so people answer questions appropriately:

1. I've flown well over 100 flights between my Mavic Pro and my Mavic Air drones
2. I've calibrated compass both on my Mavic Pro and Mavic Air successfully, when they require it, and when flying in the United States.
3. I've calibrated compass on my Mavic Pro successfully when overseas, same exact locations where I've taken my Mavic Air.
4. My Mavic Air does NOT calibrate compass when it is overseas no matter how many attempts I've tried, with and without a watch, close or far, nose up, nose down, turning it on itself or I turn with it, phone on airplane mode, off airplane mode, local phone, American phone, etc etc etc...
5. I've always used my same watch, same distance from RC and AC when calibrating compass on both drones.

I hope this will dispel people asking whether I know how to calibrate, or whether I'm wearing a watch that will do this and that, or whether I'm far or too close from the drone, etc.

Thanks.

 

[Air Beetle]

Ok great. How about a wifi connection? Did you happen to check your phone(s) on google map or other map app to see if the phone caught up to where you were standing? I'm stabbing at possible reasons and thought about my phone when I travel. Sometime after I land it still things I am at my home city.

Also, I don't own a Mavic Pro but does it also have the international restrictions like the Air? I have seen many posts about tricking the Air to unlock the US performance of FCC vs CE. Maybe it is getting confused in that way?

 

[Air Beetle]

As far as we know it looks at how far the absolute value of the magnetic field is from what it was during the last calibration.

So that might be a clue to the OP. It will range from close to the last absolute value to way off as your rotate it. Agreed?

 

[MAIRMPRO]

Ok great. How about a wifi connection? Did you happen to check your phone(s) on google map or other map app to see if the phone caught up to where you were standing? I'm stabbing at possible reasons and thought about my phone when I travel. Sometime after I land it still things I am at my home city.

Also, I don't own a Mavic Pro but does it also have the international restrictions like the Air? I have seen many posts about tricking the Air to unlock the US performance of FCC vs CE. Maybe it is getting confused in that way?

I don't know anything about international restrictions... How does it impact compass calibration? Is denying compass calibration a process to restrict flight?

When I was trying to fly the Mavic Air in Brazil, I had my spare phone with a Brazilian SIM, had used it successfully with Uber just the day before, so I assume this was not an issue. Also, I tried to fly it from the house of a friend, with access to wi-fi at one point. The other was on a remote area (beach). All flight attempts requested compass calibration, all attempts to calibrate compass failed. Twice before I had flown my Mavic Pro, using the same locations without a problem.

When I attempted to fly my Mavic Air in the Marshall Islands, I was using my American Phone. I did manage to fly it twice, at two locations, when exploring a combo of turning things on and off, changing the order of what was on and off, I was able to take off without satellite lock, and just before the calibrate compass blocked it. And in both times it eventually generated a "record home" location while in flight, and when it landed the compass calibration request came up and in both cases I was not able to fly it again, even trying the same sequences of on and off (RC, AC, phone). In both cases, one was on a remote area, the other 3ft away from a three story hotel building and next to an umbrella, it flew perfectly well, and I navigated it on very tight spaces, between trees, umbrellas, walls, etc.

 

[MAIRMPRO]

So that might be a clue to the OP. It will range from close to the last absolute value to way off as your rotate it. Agreed?

Let's see what he responds... I asked a similar question earlier... I hope this is where things would be. But then I need to know how to re-set it to a new baseline so the calibration can take place (and isn't this why calibration needs to take place in the first place? )...

 

[Kilrah]

3. I've calibrated compass on my Mavic Pro successfully when overseas, same exact locations where I've taken my Mavic Air.
4. My Mavic Air does NOT calibrate compass when it is overseas no matter how many attempts I've tried, with and without a watch, close or far, nose up, nose down, turning it on itself or I turn with it, phone on airplane mode, off airplane mode, local phone, American phone, etc etc etc...

Are you on latest firmware? Early ones had issues with calibration.
If you are, then it's probably simply defective.

It will range from close to the last absolute value to way off as your rotate it. Agreed?

No, it's the resultant (vector length) that is evaluated so independent from orientation.

 

[MAIRMPRO]

Yes, latest firmware, made all updates before getting out to fly it.
Once back in the US it calibrated on first try, NO PROBLEMS. How is that defective?

 

[Kilrah]

Really? It is defective because it didn't calibrate somewhere else and there is no reason it wouldn't if it worked correctly...

 

[MAIRMPRO]

What would be defective, on your opinion?
Thanks.

 

[Kilrah]

Could be the compass itself, or a part of the aircraft that's magnetised.

You should contact support and see what they say.