Planned launch from parking deck, Interference trouble?

[invaliduser]

I'm planning to launch from the top of a parking deck. Obviously it's reinforced with a lot of steel so I was wondering about magnetic interference. I've never launch from anywhere except the ground but hear talk of magnetic interference often. Has anyone actually had experience doing this, and if so was it notworthy?

 

[msinger]

This should be doable if you hold the Mavic above your head and hand launch it. I wouldn't launch it from the floor of the parking deck as it will likely confuse the compass.

 

[Mantra]

I've launched off many parking decks with absolutely no problem ever.

 

[Mr. Salty]

I've launched a few times from the parking deck at work with no interference issues whatsoever.

 

[dirkclod]

Think it would tell you if you shouldn't wouldn't it . I've always heard not to but I did this the other day and even checked RTH so now I don't have to hold my breath to bend over and set it on the ground . Always hand catch so that's no issue . Not a parking deck but still metal .

 

[BerndM]

I have successfully launched of the top of my SUV with no issues
YMMV

 

[invaliduser]

Sweet thanks guys!

 

[invaliduser]

Think it would tell you if you shouldn't wouldn't it . I've always heard not to but I did this the other day and even checked RTH so now I don't have to hold my breath to bend over and set it on the ground . Always hand catch so that's no issue . Not a parking deck but still metal .

Well that kinda answers my question then! [emoji4]

 

[CRCs Reality]

Not with my Mavic (just got it), but with my P3P which should act in a similar fashion..
I launched from the roof of a parking garage, no errors on launch, but once it cleared the garage the compass went haywire and I had a near flyaway. I only got it back switching to manual and using the camera feed to locate myself and fly back (this was exaggerated by the fact that the drone was directly between myself and the sun, so looking up I couldn't see it at all).
Looking back over the logs, the compass was completely confused once I cleared the structure. Consensus was that the metal in the parking garage caused the compass and GPS to orient wrong, once it was away from all of that metal the compass got a clean signal that didn't agree with the previous orientation and it flew away quickly with no input from me aside from some up-stick and yaw.
*Edit* Had I hit RTH, I'd have likely had a flyaway, as the drone didn't know where "North" was, thankfully I had read many threads where RTH resulted in a loss with compass errors so I resisted the urge (I'd by lying if I said my finger wasn't hovering above the RTH button though).

A quick video thrown together with Dashware to show what was happening during the flight..

After a compass calibration, it has worked well ever since.

 

[BudWalker]

I'm planning to launch from the top of a parking deck. Obviously it's reinforced with a lot of steel so I was wondering about magnetic interference. I've never launch from anywhere except the ground but hear talk of magnetic interference often. Has anyone actually had experience doing this, and if so was it notworthy?

There are several variables that determine if a scenario like your planning will lead to a fly away. Fortunately, you can get the Mavic to tell you if it has a compromised Yaw value which may lead to a fly away. Just look at the red triangle in the Go App map display that shows what the Mavic thinks the heading is. If that doesn't point in the right direction then the Yaw is compromised.

 

[BudWalker]

Think it would tell you if you shouldn't wouldn't it . I've always heard not to but I did this the other day and even checked RTH so now I don't have to hold my breath to bend over and set it on the ground . Always hand catch so that's no issue . Not a parking deck but still metal .

I can think of a couple of reasons that you aren't experiencing a compass issue.

If the battery is turned on in a location that isn't distorted the Yaw value gets set with the correct value since compass is correct. If the AC is then moved to the bed of the truck it can take between 30 and 90 seconds for the Yaw to change to the incorrect compass value. Presumably, this isn't the case since you've done this quite often and would have encountered a problem at least once.

The other thing to consider is that the distortion will be the greatest at the edges of a relatively large piece of metal. That's because the metal "steals" by bending some of the flux lines from non-metal region next to it. In the center there will be less distortion.

You could try an experiment. Place the Mavic at the edge, turn on the battery and then observe the red triangle in the Go App map display to see if it's pointed the right way. Having the Mavic already turned on and then moving it around isn't a good test because the Yaw value is only loosely coupled to the compass. I.e, there is at least a 30 sec delay before the Yaw will be the same as the compass.

Can you provide a .DAT for one of your truck launches?