Novice Mistake but got lucky!

[JenksKenny]

I thought flying through an old steel bridge would make a good video. I should have realized the potential danger. Steel and radio signals don't mix well. Got lucky though. See video. Effects of steel on drone Control

 

[Magilla Gorilla]

So glad you made it! Thanks for the video. I will mark that off my list of things to do!

 

[STUFF2C]

Looks like the bridge spit it out...

 

[JDawg]

Love the low key sound effects, perfect. This is why it is a good idea to be able to switch to atti and know at least a little bit how to fly in atti.

 

[Porky]

I personally would of landed straight away when I realised I didn’t have full control, but glad you got out with no damage bet you won’t do that again..

 

[FormerMember07122019_2]

This may surprise some folks but I am a little bit shocked that it happened. Yes, steel will have a negative effect on radio signals but unless you were pretty far away (like a mile or more) it shouldn’t have affected (or is it effected) the signal enough to lose control. To block 2-6GHz signals would take a steel mesh like a window screen (or solid) not something with relatively large openings like that bridge. On top of that it looks like you were standing (I’m not positive) on the road with direct line of sight to the aircraft.

 

[JenksKenny]

I was in line of site the whole time, maybe 75 yards away at first, then moved quickly toward the bridge. I had some control for a while, but not enough and was really surprised when it took the sudden move to the right between bridge supports. When I moved it right or left it kept drifting in that direction even after I released the joystick. I agree with the earlier comment that I should have landed right away. I thought I could still make it through at first, though. Too stubborn, I guess. I don't understand exactly why the partial loss of control happened. I have a lot to learn like how to fly in ATTI. I appreciate the comments and suggestions.

 

[old man mavic]

in this case it wasnt so much about loss of signal but the affect on the compass which made it go into atti mode the poor drone didnt have a clue where it was you were very lucky it did not crash into the bridge or go in the water

 

[madkaw]

And to think, I was gonna go through a similar bridge today...omg. Jenks thanks for the video.

 

[DesG]

The radio problem is probably not so much signal blocking but signal reflection. The aircraft could receive the same signal three or four times with slight time differences. This could well confuse it. Higher frequencies are very prone to this effect.

 

[FormerMember07122019_2]

After I thought about this a little bit more I realized that there are multiple things controlling the aircraft; GPS, compass, barometer, accelerometer, vision systems, and ultrasonic systems. I don’t believe it was loss of signal, or loss of GPS (although possible). The most likely culprit is probably compass interference as Old Man Mavic mentioned, due to the large amount of metal, although the compass should just impact it’s directional orientation but not necessarily cause loss of control. I must admit here that I do not know the algorithm of how the craft takes all of these inputs and combines them to control it’s position. It could also be signal reflection as mentioned by DesG but I think that is unlikely because it would take larger flat surfaces and the system is probably designed to deal with multi-path as any decent RF system.

It would very interesting, at least to me, for someone to review the flight log to see what may have caused the problem.

JanksKenny - Was there any warnings on the controller or the app?

 

[BRDVPRA]

I have a similar incident with a steel bridge to. I will post video later. I was 50ft away and the drone just started drifting...

 

[old man mavic]

it drifts because it is no longer in GPS and is in ATTI mode and then needs constant inputs from the pilot to keep it steady

 

[Casemanmi]

Wonder if that would happen if you were walking behind the drone to get the shot?

 

[old man mavic]

i think that the presence of all that steel would still give a compass error no matter how near you were to the drone

 

[JDawg]

Loss of GPS would not make it shoot out the side of the bridge the way it did unless Jenks instructed it to or there was a gust of wind. It would be cool to see the flight log. I think this is compass intereference all the way.

 

[sar104]

If you want to know exactly what caused the issues, rather than generating completely random guesses, then post the flight log.

 

[JDawg]

If you want to know exactly what caused the issues, rather than generating completely random guesses, then post the flight log.

Was my guess that bad

 

[sar104]

Was my guess that bad

No - that would have been my first guess too. But it could also have been the obstacle avoidance system being confused.

 

[FormerMember07122019_2]

Hey sar104, some of us enjoy hypothesizing.