What was that? Weird glitch in flight (video)

[saltydrone]

I was flying tonight, about 30 minutes after sunset, over the woods. Gimbal pointing straight down, shooting 4k video. It was a calm night with almost no wind. I had just been hovering low over tree tops, and the trees were calm with no movement (e.g. no wind).

Everything was going fine, until at one point I pushed the right stick to the right, to move the drone straight to the right. I noticed it didn't respond, so I held the stick all the way to the right, for maybe a second or two. The video feed (and recorded 4k video) show it then snapping to the right. I instantly got a high wind alert on the screen, though I'm absolutely confident there were not high winds. I pushed back left and it delayed briefly and snapped back to the left, exhibiting the same strange behaviour. It snapped back and forth several more times while I struggled to get a hold of it.

I've never experienced anything like that before, and didn't like it, so I initiated RTH and landed it asap. It seemed normal during the return and the manual landing.

Phantom Help Logs

Any ideas what this is?

 

[Eagle Eye 62]

I was flying tonight, about 30 minutes after sunset, over the woods. Gimbal pointing straight down, shooting 4k video. It was a calm night with almost no wind. I had just been hovering low over tree tops, and the trees were calm with no movement (e.g. no wind).

Everything was going fine, until at one point I pushed the right stick to the right, to move the drone straight to the right. I noticed it didn't respond, so I held the stick all the way to the right, for maybe a second or two. The video feed (and recorded 4k video) show it then snapping to the right. I instantly got a high wind alert on the screen, though I'm absolutely confident there were not high winds. I pushed back left and it delayed briefly and snapped back to the left, exhibiting the same strange behaviour. It snapped back and forth several more times while I struggled to get a hold of it.

I've never experienced anything like that before, and didn't like it, so I initiated RTH and landed it asap. It seemed normal during the return and the manual landing.

Any ideas what this is?

No idea but I experienced something very similar except the gimbal freaked out and got out of alignment and the drone did not respond to stick input. It was my first flight after I did the latest update and I did not have any issues before that. Have you updated to the most recent firmware by chance?

 

[saltydrone]

No idea but I experienced something very similar except the gimbal freaked out and got out of alignment and the drone did not respond to stick input. It was my first flight after I did the latest update and I did not have any issues before that. Have you updated to the most recent firmware by chance?

Yeah, I'm running the most recent firmware version....

 

[Yorkshire_Pud]

Just to check whether there was wind, upload the log to DJI Flight Log Viewer | Phantom Help
and then scroll across the log replay and watch the artificial horizon especially when the drone is hovering. If during a hover the horizon is tilted, elevated or lowered there was wind.

I don't remember if an artificial horizon can be displayed in the App's replay of a log.

If it was a glitch, sorry can't help.

 

[globetrotterdrone]

I suspect it has to do with the wind.

As we can see at the beginning that "Strong wind" was reported, I remember flying out in the breezy coastal areas, the drone was eagerly trying to hold position to finish a panorama.

The gimbal movement became quite erractic for a very short time while looking at the controller.

That's my guess.
For a deeper analysis you should as @Yorkshire_Pud pointed out, provide the log and the experts may have a look to see if there's something else.

Personally, keep an eye on it but I am mostly sure it was due to the strong wind involved.
You were > 100 m high so on the ground it can be easily misjudged, especially if gusts come into play.

 

[saltydrone]

Just to check whether there was wind, upload the log to DJI Flight Log Viewer | Phantom Help
and then scroll across the log replay and watch the artificial horizon especially when the drone is hovering. If during a hover the horizon is tilted, elevated or lowered there was wind.

I don't remember if an artificial horizon can be displayed in the App's replay of a log.

If it was a glitch, sorry can't help.

Here is the flight on Phantom Help - certainly open to any interpretation.

I think I started pushing right (and not seeing any reaction) at about 14m 47s, give or take a second.

I definitely get that high level flights can run into wind that is not felt down low, though in my ~10hrs of total flight time with this drone, even in legitimately windy conditions (e.g. blowing away my landing pad), it never gave me the wind warning or had the same behaviour. So I'd be surprised given the observed conditions and how it behaved up until that moment, but understand that sometimes the best answer is the most obvious one.

 

[Mike107]

The behavior you report is the same as when I try to land on a particular landing mat of mine. The drone fights lateral and fore/aft commands until it is no longer over the (too shiny?) mat, then Bazoom! if I am not careful. It doesn’t do the same on a second and third test mat. Vision sensors were always clean.

I wonder if the conditions prompting the low ambient light/sensor warnings are a creating a similar situation for you?

Just a thought.
Mike107

 

[Yorkshire_Pud]

Here is the flight on Phantom Help - certainly open to any interpretation.

Hmmmm all the high hovers (very low to zero speed) are more or less of short duration so difficult to impossible to see what the wind was but airdata thinks the wind speed was 7.6mph / 3.4m/s so nothing significant.
Attached are some CsvView charts that speed & height vs drone pitch and roll, roll peaks at 38deg @ 14:51.8 which is fairly steep, maybe there was a gust.
Whether or not it is the cause of you "snapping" I am not skilled enough to guess, sorry.

 

[FLDave]

I suspect that you really don't know what the wind was like at 800 feet from home and at 350 ft ATL as you most likely could not visually identify the drone to interpret what was happening. The wind can change dramatically based on terrain and height. Fortunately you did have a successful RTH.