Mavic 3 Lost Control Near Boat

[Tim3459575]

Hi,

I had a very hard time getting my M3 back to land on my sailboat today. I had OA turned off and I've done this many times without problems. The drone behaved normally until it got about 20' from the boat and then it became very erratic wandering all over without stick inputs. Every time I moved it further away, it became rock steady. It seemed like something on the boat was causing interference. My boat has a 60' mast with typical stainless steel rigging - could that be a factor ? In 3 years of flying Mavic drones, I've never seen anything like this. Attached is the flight log that shows the crazy movements as it got close to the boat. Another theory is that perhaps my Starlink WIFI or other electronics may be creating some sort of interference. Could that have affected the drone ? I've done at least 50 flights off the boat before and never turned off the WIFI or seen that kind of behaviour. In any case, apparently my drone has all of a sudden decided it doesn't want to get closer than 20' to my boat without becoming nearly uncontrollable.

Any suggestions as to the cause of this and how to prevent this situation in future would be much appreciated.

thank you,
Tim

DJI Flight Log Viewer | Phantom Help

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[Meta4]

It seemed like something on the boat was causing interference. My boat has a 60' mast with typical stainless steel rigging. In 3 years of flying drones, I've never seen anything like this. .. Another theory is that perhaps my Starlink WIFI or other electronics may be creating some sort of interference. Could that have affected the drone ?

I don't know about Starlink, but nothing else you listed would have had any effect.
I don't think Starlink would either.
I'll dig into the data and see if I can find anything helpful.

 

[Meta4]

Any suggestions as to the cause of this and how to prevent this situation in future would be much appreciated.

It's hard to spot the problem in the data because you were making so many small joystick inputs and pausing between them.
There's no simple point where I can see the drone refusing to respond to your joystick inputs.
You were in Tripod Mode the whole time, so speeds were slow.

The one thing I do see is from about 18:47 the drone shows low speed movement without a corresponding joystick input.
This is particularly noticeable from 19:39 to 19:43.6.
But what's causing this isn't clear to me.
Perhaps @slup would like to see what he can see?

 

[Reactor2015]

Put it on sport mode. Maybe the sensor are being tricked of what they see.

 

[Tim3459575]

thanks for the comments, further background as follows:

initially it was on tripod mode (or c). I had OA turned off, and was trying to bring it alongside the boat prior to the final approach to the deck. However, it was behaving like it was in an a 50mph wind and could not hold its position. I waa frantically trying to position it while it was moving around on it’s own, hence all the stick inputs (trying to keep it from hitting the rigging since OA was turned off). Eventually I switched it to N mode and had slightly more control so that I was able to crash land it on the deck.

 

[AnzacJack]

Maybe the 50mph wind was very turbulent close to the boat, giving the drone some problems trying to remain stable?
No idea, but just a thought

 

[Meta4]

Maybe the 50mph wind was very turbulent close to the boat, giving the drone some problems trying to remain stable?
No idea, but just a thought

If there was a 50 mph wind, the drone would have simply blown away and the OP would have had more important things to deal with than a drone.
But there was no 50 mph wind.

 

[Meta4]

Put it on sport mode. Maybe the sensor are being tricked of what they see.

The data doesn't show his drone being't fooled by obstacle avoidance and coming to a stop.
And he mentioned that the OA was disabled.

 

[Yorkshire_Pud]

If you think it's interference from on board wifi etc. it might be informative to try combinations of height and distance to see whether or not you could 'map out' the boundary of a hemisphere of influence.

 

[Tim3459575]

Maybe the 50mph wind was very turbulent close to the boat, giving the drone some problems trying to remain stable?
No idea, but just a thought

it was behaving “like” there was 50mph wind. wind was light, prob no more than 10 mph. If it was wind induced, it should have happened when hovering further from the boat in the same manner is it did closer in. The hover was perfectly stable if it was more than approx 20’ from the boat in the same light wind.

 

[Tim3459575]

If you think it's interference from on board wifi etc. it might be informative to try combinations of height and distance to see whether or not you could 'map out' the boundary of a hemisphere of influence.

I need to get to a dock and test “shutting off” the wifi during close approach, but it seems a bit unlikely that the wifi would start to cause interference after 50 normal flights in close proximity to it. I’m currently in a remote area on the BC coast, and will not fly from the boat while at anchor until I get this resolved. Need to be at a dock where alternate landing is possible in case it happens again.

PS: my WIFI is part of a Starlink system, which includes router and dish. So perhaps it could be the dish rather than the router.

 

[Tim3459575]

found this in Droneblog and suspect it must be a WIFI interference issue. (I have 2 onboard WIFI - Starlink and Vesper AIS)

Do WiFi signals interfere with drones?​

If you experience a sudden loss of control while flying your drone, you should know that this isn’t uncommon. If your drone doesn’t respond to your instructions, then the chances are that there’s signal interference between the transmitter and the receiver.

If the controller system checks out okay, then most likely you have an issue with signal interference. Finding out exactly where the source of signal interference is coming from will make sure that you don’t lose control of your drone.

Most drone transmitters usually operate on the 2.4GHz band of the radio spectrum. The bad news is that cellular network towers and WiFi routers also use the 2.4GHz frequency. Therefore, any WiFi signals in the area you are flying your drone may interfere with the signal between your controller and your drone.

 

[Crash Pro]

I’ve been practicing flying manually with my DJI FPV drone and found that one area where I fly, my drone acts goofy and almost does the opposite of what my stick inputs are.

There are telephone poles surrounding the field where I fly, and there is a radio tower close by, along with homes situated directly behind me. I figure it’s interference from one or more of these items. The interference got so bad that I had to find a new place to fly.

I’d suggest pulling the plug on you WIFI/ Starlink and see if your drone responds normally.

 

[Phantomrain.org]

If the drone reacted better when you were in N mode , most likely you need to turn on and off the Sport mode before you got close to the Boat, an the sensors get confused.

Phantomrain.org
Gear to fly in the Rain, Land on the Boat and Float on the Water.

 

[RodPad]

I have looked in Starlink recently I have a neighbor that got it for his Sailboat.
Question: is how long have been using Starlink?

The WiFi signals it and other routers send out, I don't think so.
The only factor is it sending and receiving to, low orbit satellites, Leos? That are not Geostationary.
Its transmission / receiving antenna, would be kind of wide?

That's all I got for now.

Rod ..

 

[Arnold LeVine]

What does the warning low visibility mean?

 

[Phantomrain.org]

What does the warning low visibility mean?

That the sensors do not have enough light to work correctly.

Phantomrain.org
Gear to fly in the Rain. Land on the Water.

 

[Tim3459575]

What does the warning low visibility mean?

there was a bit of patchy fog so that warning was appropriate. I dropped down out of the fog cloud to deal with it.

 

[Tim3459575]

What does the warning low visibility mean?

there was a bit of patchy fog so that warning was appropriate. I dropped down out of the fog cloud to deal with .

I have looked in Starlink recently I have a neighbor that got it for his Sailboat.
Question: is how long have been using Starlink?

The WiFi signals it and other routers send out, I don't think so.
The only factor is it sending and receiving to, low orbit satellites, Leos? That are not Geostationary.
Its transmission / receiving antenna, would be kind of wide?

That's all I got for now.

Rod ..

Interesting concept re the antenna. It’s called “phased array” and not parabolic (focused) so yes, I assume it could be a very wide beam pattern. The drone was approaching the side of the boat with the Starlink antenna when the problem occurred. Tried it this morning Starlink off and it seemed to be better.

 

[RodPad]

there was a bit of patchy fog so that warning was appropriate. I dropped down out of the fog cloud to deal with .

Interesting concept re the antenna. It’s called “phased array” and not parabolic (focused) so yes, I assume it could be a very wide beam pattern. The drone was approaching the side of the boat with the Starlink antenna when the problem occurred. Tried it this morning Starlink off and it seemed to be better.

So, how long have been using starlink?

Rod ..