Mavic Mini Fly Away?

[boblui]

On the MA2 site a few days ago someone posted a nice video in which his MA2 took off from and landed on the bonnet of his car. I asked him about the car's metal influencing the drone's compass, and he said there was no influence: the simple fact is that he took off, flew well, and landed normally. So why should steel rods embedded in concrete cause interference?

If the guy powered on the drone on the bonnet of the car, it is likely that the drone will suffer from yaw error. Once the drone is powered on and the initial direction set base on the magnetic field, it will be using the rate gyros mainly for sensing the direction so magnentic field disturbance will not affect it.

A demo video I made earlier :

 

[Meta4]

Why should steel rods embedded in concrete cause interference?

See the link I added in post #12.

 

[Hi-Flyer]

See the link I added in post #12.

Where do I find post #12. Couldn't you just repost the link?

 

[DanMan32]

Each post in a thread has a sequence number and the timestamp it was submitted.

In the app version of this site (which is what I usually use, needs updating), it is in the upper right corner of a post.

 

[slup]

... his MA2 took off from and landed on the bonnet of his car. I asked him about the car's metal influencing the drone's compass, and he said there was no influence...

So why should steel rods embedded in concrete cause interference?

See 2 explanations to that ...

1. The MA2 wasn't powered on standing on the bonnet ... this as it's only then the IMU initialization gets screwed up by a disturbed compass.

2. The bonnet was made of ... aluminium?

A steel bonnet will definitely disturb the compass & if the drone then & there is powered on the IMU will be set to a wrong direction.

 

[Camino Ken]

There is less and less metal in cars these days. A lot more composite materials. Having said that I cannot takeoff anywhere near my truck without problems.

Just curious - why would a car be wearing a hat? ???

 

[Hi-Flyer]

Each post in a thread has a sequence number and the timestamp it was submitted.

In the app version of this site (which is what I usually use, needs updating), it is in the upper right corner of a post.

10x.

 

[djmcdrone]

I live in Alberta and this summer the mosquitoes were so bad that I would launch my mini from the sunroof of my 2019 f 150. Never did I have any control issues other than weak signal on occasion which I rectified by turning the truck so the signal was going out the drivers window. Still got bitten badly but for the love of flying it was a small price to pay.

 

[DanMan32]

10x.

?

 

[DanMan32]

There is less and less metal in cars these days. A lot more composite materials. Having said that I cannot takeoff anywhere near my truck without problems.

Just curious - why would a car be wearing a hat? [emoji12][emoji12][emoji12]

That and shoes.

 

[teeroy]

I live in Alberta and this summer the mosquitoes were so bad that I would launch my mini from the sunroof of my 2019 f 150. Never did I have any control issues other than weak signal on occasion which I rectified by turning the truck so the signal was going out the drivers window. Still got bitten badly but for the love of flying it was a small price to pay.

I hear you. We had them terrible up here this season, can't remember a wetter spring/summer than this past year. Was so bad I bought a couple Thermacell units out of desperation...I was pleasantly surprised at their effectiveness. Recommend.

 

[Thomas B]

I hear you. We had them terrible up here this season, can't remember a wetter spring/summer than this past year. Was so bad I bought a couple Thermacell units out of desperation...I was pleasantly surprised at their effectiveness. Recommend.

What worried me on the Texas Gulf Coast was hearing a little voice in the midst of a mosquito horde saying “wanna eat here or take it home”

 

[Sallee]

If the guy powered on the drone on the bonnet of the car, it is likely that the drone will suffer from yaw error. Once the drone is powered on and the initial direction set base on the magnetic field, it will be using the rate gyros mainly for sensing the direction so magnentic field disturbance will not affect it.

A demo video I made earlier :

sorry for rising up this tread from dead, but i am curious..
If your compass had been influenced by magnetic interfirence, then when u open the map will dron would not be point in right direction? U can use some reference point, some road for exemple, just point it at the road and then look at the map, if drone is not pointed on the road does it mean that your compass is not calibrated properly?

 

[Meta4]

U can use some reference point, some road for exemple, just point it at the road and then look at the map, if drone is not pointed on the road does it mean that your compass is not calibrated properly?

No .. the compass in the drone is properly calibrated.
Generally, if the drone's compass is calibrated, it's calibrated properly.

If the drone icon on the map was not pointing the same direction as the real drone, that would indicate that the compass was reading incorrectly.
The most likely cause would be nearby steel objects making the compass respond to the magnetic field of the steel, rather than that of the earth.

That causes a problem because the IMU uses the compass reading to initialise gyro sensor on startup.

 

[Sallee]

No .. the compass in the drone is properly calibrated.
Generally, if the drone's compass is calibrated, it's calibrated properly.

If the drone icon on the map was not pointing the same direction as the real drone, that would indicate that the compass was reading incorrectly.
The most likely cause would be nearby steel objects making the compass respond to the magnetic field of the steel, rather than that of the earth.

That causes a problem because the IMU uses the compass reading to initialise gyro sensor on startup.

ok, i get u but also i dont my question is if people should also check if drone is pointing in same direction in real and in the map, as some pre flight check.. if its not pointing that mean that your compass had some interference and u should move from that position a bit, and calibrate compass again (even if FC is not suggesting u need to do it)
i am saying that because i had one situation like that, drone was not pointing correctly on the map and FC didnt give me message that i should calibrate my compass.. i move few metters calibrated compass then i started flying without problems

 

[Meta4]

if its not pointing that mean that your compass had some interference and u should move from that position a bit, and calibrate compass again (even if FC is not suggesting u need to do it)
i am saying that because i had one situation like that, drone was not pointing correctly on the map and FC didnt give me message that i should calibrate my compass.. i move few metters calibrated compass then i started flying without problems

There's no need to recalibrate the compass because it's already properly calibrated.
It's normal for a properly working compass to be deflected when you place it close to something steel.
The problem is the location close to the steel, not the compass.
The solution is to move away from the problem.

Recalibrating the compass only measures the magnetic fields that are part of teh drone.
It can't "fix" problems that are outside the drone.

 

[Sallee]

There's no need to recalibrate the compass because it's already properly calibrated.
It's normal for a properly working compass to be deflected when you place it close to something steel.
The problem is the location close to the steel, not the compass.
The solution is to move away from the problem.

Recalibrating the compass only measures the magnetic fields that are part of teh drone.
It can't "fix" problems that are outside the drone.

ok, if i understood u corectly u are saying even if drone is ok calibrated when u put it close to metal pointer on map would not be correct right? but when it take of drone will be away from interference and it will be all ok with that flight???
also my question is how can drone know that its compass i properly calibrated if u power it on at place with interference?

 

[Meta4]

ok, if i understood u corectly u are saying even if drone is ok calibrated when u put it close to metal pointer on map would not be correct right? but when it take of drone will be away from interference and it will be all ok with that flight???

That is correct.
But if you ever did have that problem and had to move, you should power down, move and power up at the new location.

also my question is how can drone know that its compass i properly calibrated if u power it on at place with interference?

If your compass was properly calibrated last time you flew, it should be properly calibrated now.
The compass doesn't lose calibration unless you modify the drone.
It doesn't need frequent recalibration.
I haven't ever calibrated the compass in my main working drone in the 4.5 years I've had it.

The first post in this thread gives a good explanation of what compass calibrating actually does.

A short explanation of compass function, calibration and errors.

BACKGROUND The aircraft compass is often misunderstood, both in terms of function and purpose, but it is important to understand what the compass measures, why, and what happens to that information. At the most basic level the purpose of the compass is to measure the earth’s magnetic field in...

mavicpilots.com

 

[Sallee]

That is correct.
But if you ever did have that problem and had to move, you should power down, move and power up at the new location.

If your compass was properly calibrated last time you flew, it should be properly calibrated now.
The compass doesn't lose calibration unless you modify the drone.
It doesn't need frequent recalibration.
I haven't ever calibrated the compass in my main working drone in the 4.5 years I've had it.

The first post in this thread gives a good explanation of what compass calibrating actually does.

A short explanation of compass function, calibration and errors.

BACKGROUND The aircraft compass is often misunderstood, both in terms of function and purpose, but it is important to understand what the compass measures, why, and what happens to that information. At the most basic level the purpose of the compass is to measure the earth’s magnetic field in...

mavicpilots.com

yes, i am referring to this treed and i have red it
here is response from this guy who wrote this

A short explanation of compass function, calibration and errors.

The sky for the info. Especially the pre flight things to check. I have made it point to check the orientation on the map but not the interference screen. Paul C

mavicpilots.com

i mean, if u have this situation its logical that u should change position because u have some sort of interference on compass, and why not re-calibrate it?
If i i got this all right, when u power on drone and its doing sistems check up, if u are in some sorth of magnetic interference while its powering on then your compass wont be accurate = unsafe to take off

 

[Thomas B]

yes, i am referring to this treed and i have red it
here is response from this guy who wrote this

A short explanation of compass function, calibration and errors.

The sky for the info. Especially the pre flight things to check. I have made it point to check the orientation on the map but not the interference screen. Paul C

mavicpilots.com

i mean, if u have this situation its logical that u should change position because u have some sort of interference on compass, and why not re-calibrate it?
If i i got this all right, when u power on drone and its doing sistems check up, if u are in some sorth of magnetic interference while its powering on then your compass wont be accurate = unsafe to take off

If you move the drone a few feet or off of concrete the magnetic interference will go away