Get more from your Mavic
The largest Mavic community in the world
Join Us Now

Compass error. Unstable flight.

BrazilMan

Member
Joined
Jun 13, 2018
Messages
7
Reactions
2
Age
34
I have a problem. I magnetized the compass of my drone (very stupidly - put a magnetic tape measure on the drone at night) Interference in the red zone. I read many articles on the forum. What is the best way to proceed? Change the compass? (Coliberation does not help) Or demagnetize in different ways ?? Which way would you advise?
 
  • Like
Reactions: Former Member

Former Member

Well-Known Member
Joined
Dec 20, 2016
Messages
14,014
Reactions
13,090
Location
Duluth, Georgia
Most likely you have magnetized metal components, such as screws, that are close to the compass. Demagnetization, followed by a compass calibration, should fix that.

@sar104 have you ever demagnetized a Mavic? Im just curious as to how you would proceed in terms of equipment and procedure. If 1 compass was showing errors, would you do them both anyway?

Edit: In most of my repairs, compass #2 is fine, it's compass #1 that is faulty.
 

sar104

Dic mihi solum facta, domina.
Premium Pilot
Joined
May 27, 2017
Messages
12,789
Reactions
16,554
Location
Los Alamos, NM
@sar104 have you ever demagnetized a Mavic? Im just curious as to how you would proceed in terms of equipment and procedure. If 1 compass was showing errors, would you do them both anyway?

I've only demagnetized Phantoms. On the Mavic I would probably remove the shell and see if I could identify the magnetized components, and then decide whether to demagnetize in place or remove them first.

This question appears to be about the MA, which only has one compass. On an aircraft with two compasses, whether to do both would likely depend on the exact nature of the problem and what had become magnetized.
 
  • Like
Reactions: Former Member

sar104

Dic mihi solum facta, domina.
Premium Pilot
Joined
May 27, 2017
Messages
12,789
Reactions
16,554
Location
Los Alamos, NM
Its easy to remove either compass on the Mavic so I guess removing them would be better.

Agreed. Although, again, the other important thing to check is whether it's part of the compass assembly itself that is magnetized, or some other nearby item/component. It won't help removing and demagnetizing the compass if that is not actually the problem.
 
  • Like
Reactions: Former Member

Former Member

Well-Known Member
Joined
Dec 20, 2016
Messages
14,014
Reactions
13,090
Location
Duluth, Georgia
Agreed. Although, again, the other important thing to check is whether it's part of the compass assembly itself that is magnetized, or some other nearby item/component. It won't help removing and demagnetizing the compass if that is not actually the problem.

True. If you remove it to demagnetize it, then reinstall it and it gets magnetized again, the problem will persist. I just usually replace the whole compass #1/GPS assembly since its just 2 screws.
 

sar104

Dic mihi solum facta, domina.
Premium Pilot
Joined
May 27, 2017
Messages
12,789
Reactions
16,554
Location
Los Alamos, NM
True. If you remove it to demagnetize it, then reinstall it and it gets magnetized again, the problem will persist. I just usually replace the whole compass #1/GPS assembly since its just 2 screws.

It's not necessarily that it might get magnetized again - it's just the influence of nearby magnetic fields on the compass measurements. I'm not sure that there is anything in a MEMS compass itself that can become magnetized - I'd suspect its mounting screws first, then other adjacent metal parts.
 
  • Like
Reactions: Former Member

Canuk

Well-Known Member
Joined
Apr 19, 2018
Messages
920
Reactions
838
Age
55
I am not sure if I had some dumb luck or what but this is my story :: lol

I have a mavic Pro and it flew flawless .
Then one time after flying when I put it away in the office I sat it on top of a piece of exercise equipment of my wife’s . I did not think anything about it. Turns out sitting on the machine for a week messed it up . This exercise equipment has a 1/4 horse Electric motor mounted in it . My drone bag was sitting on the platform of it for a few days .
The next time I flew the drone I was getting lots of gps errors and gps redundancy . Then I would get atti mode . My phone screen would fill with warnings . The drone would not even hover in one spot with zero wind . I was about to send it in , then after watching ten million U-tube videos I came across a thing called
C-fixer .
I thought what the hell . Worse case I waste some more money and the drone is not usable anymore .
I got the little tool and did my demagnetizing and I then pulled up The compass interference screen and it was clear .
So I levelled my kitchen table and then drove out into the sticks where I was 25 miles from any source of civilization . I did the compass calibration thing . My drone works 100% again . I then later got some small steel screws magnetized them by rubbing them on a magnet and this little tool is able to take the magnetized screws and put them back normal again . Maybe it’s just dumb luck but my drone stayed home and I live in northern Alberta so my down time would of been a long time if I sent it in to get my mistake fixed .
 
  • Like
Reactions: sar104

BrazilMan

Member
Joined
Jun 13, 2018
Messages
7
Reactions
2
Age
34
@sar104 have you ever demagnetized a Mavic? Im just curious as to how you would proceed in terms of equipment and procedure. If 1 compass was showing errors, would you do them both anyway?

Edit: In most of my repairs, compass #2 is fine, it's compass #1 that is faulty.
mavic air has 1 compass!!! ???
 

BrazilMan

Member
Joined
Jun 13, 2018
Messages
7
Reactions
2
Age
34
Agreed. Although, again, the other important thing to check is whether it's part of the compass assembly itself that is magnetized, or some other nearby item/component. It won't help removing and demagnetizing the compass if that is not actually the problem.
I can demagnet the neighboring parts
 

BrazilMan

Member
Joined
Jun 13, 2018
Messages
7
Reactions
2
Age
34
I am not sure if I had some dumb luck or what but this is my story :: lol

I have a mavic Pro and it flew flawless .
Then one time after flying when I put it away in the office I sat it on top of a piece of exercise equipment of my wife’s . I did not think anything about it. Turns out sitting on the machine for a week messed it up . This exercise equipment has a 1/4 horse Electric motor mounted in it . My drone bag was sitting on the platform of it for a few days .
The next time I flew the drone I was getting lots of gps errors and gps redundancy . Then I would get atti mode . My phone screen would fill with warnings . The drone would not even hover in one spot with zero wind . I was about to send it in , then after watching ten million U-tube videos I came across a thing called
C-fixer .
I thought what the **** . Worse case I waste some more money and the drone is not usable anymore .
I got the little tool and did my demagnetizing and I then pulled up The compass interference screen and it was clear .
So I levelled my kitchen table and then drove out into the sticks where I was 25 miles from any source of civilization . I did the compass calibration thing . My drone works 100% again . I then later got some small steel screws magnetized them by rubbing them on a magnet and this little tool is able to take the magnetized screws and put them back normal again . Maybe it’s just dumb luck but my drone stayed home and I live in northern Alberta so my down time would of been a long time if I sent it in to get my mistake fixed .
Good story. I want to buy this device myself - CFixer. Now I can demagnetize the compass in the service. They have this device.
 

Canuk

Well-Known Member
Joined
Apr 19, 2018
Messages
920
Reactions
838
Age
55
US$77

How common is this problem?

I would think if your drone is not ever set beside speakers or electrical motors it should not be a common problem .
My phantom would hover in about a 10’ circle if given 10 minutes. After I used the C-fixer it now will hover in about a 2’ circle in the very same spot in my yard . It’s a old P2
So after using it on my mavic and the P2 the results show me the C-fixer helps and is not snake oil . I was about to send my mavic in but now it’s fine . I live in Canada so I paid way more because of shipping and currency exchange rate . But it was money well spent
 
  • Like
Reactions: swooshdave

BrazilMan

Member
Joined
Jun 13, 2018
Messages
7
Reactions
2
Age
34
The MA has dual IMUs but only one magnetic compass. The second "compass" is a vision (camera-based) compass that there is little or no documentation on but which, presumably, detects yaw visually.
very interesting information. Thank you
 
DJI Drone Service

New Threads

Forum statistics

Threads
104,148
Messages
1,206,304
Members
132,833
Latest member
droneecitygetbusy