Weird gimbal movement - August 4, 2018

[pmshop]

As I always seem to get a flight "into the sunset" I wanted to mix it up and get a flight "away from the sunset" but was surprised at the results. With a 7mph (3.1m/s) wind from behind according to UAV Forecast, I started to fly into the wind backwards. All of the sudden, the view/ gimbal starts to mover upward without commanding it to do so. According to the logs, I also lost about 235ft (72m) over 20 seconds. Then the altitude and gimbal self corrected. All behavior could be replicated on the same flight.
Attached are the video, log and Phantom Help analysis

DJI Flight Log Viewer - PhantomHelp.com

 

[graywoulf]

You having flight problems? This is serious. You never have problems with your Spark. I guess that the flight log you posted has to be opened in another program other than Windoze Notebook.

 

[pmshop]

You having flight problems? This is serious. You never have problems with your Spark. I guess that the flight log you posted has to be opened in another program other than Windoze Notebook.

the raw log in the zip folder, yes.
The link to Phantom Help is a browser link to Phantom Help analyzer results.
That can open anywhere.

Seriously I think it was the wind but it was strange seeing the gimbal compensate as it did flying backwards into the wind.

 

[graywoulf]

That had to be a serious wind gust. But to happen twice? Hmmmm

 

[landude]

Cell three on your battery started getting weird around 3m 49s, I bet that was the cause.

 

[pmshop]

Cell three on your battery started getting weird around 3m 49s, I bet that was the cause.

But it was duplicated without a drain on the other cycle?
There might be something to flying into the wind backwards too.

 

[Koala Tails]

I can’t help with the answer.
I have a question,it looks like you were near 400ft, was that in sport mode?
It was difficult to see any movement other than the unexpected gimbal shift & course correction tilt.

 

[pmshop]

I can’t help with the answer.
I have a question,it looks like you were near 400ft, was that in sport mode?
It was difficult to see any movement other than the unexpected gimbal shift & course correction tilt.

Yes, 400ft...that's it
Sports mode backwards into the wind.
That is exactly what I mean...the unexpected gimbal shift up during that flight backwards.

 

[Koala Tails]

If it was not movement in the gimbal, instead the quad went “nose down” into a dive, (it would be *** down). This would explain the loss of altitude.
Why it dives consistently? Something to do with the terrain, a body of water or mountain. Wind gusts or down drafts.
I’m guessing.
I will avoid flying backwards in sport mode, it could be a design fault.

 

[pmshop]

If it was not movement in the gimbal, instead the quad went “nose down” into a dive, (it would be *** down). This would explain the loss of altitude.
Why it dives consistently? Something to do with the terrain, a body of water or mountain. Wind gusts or down drafts.
I’m guessing.
I will avoid flying backwards in sport mode, it could be a design fault.

Cannot be any of those except for design flaw because it could be reproduced.
But surely someone would have found it before now?

 

[Spark 317]

Cannot be any of those except for design flaw because it could be reproduced.
But surely someone would have found it before now?

I think I read in one of your posts that you changed a value in the firmware for better yaw, or something along those lines.

Do you think those changes would affect the Spark in backward flying?

Maybe go back to stock and try again?

You got me thinking about flying backwards in Sport mode when I get a chance to see if I get similar results.

 

[pmshop]

I doubt it would affect it.
This wasn't with YAW but the gimbal pitching up by itself flying backwards.

The only things I have changed form stock that are not user redily available was the rate of YAW (90°/sec to 30°/sec) and changed the YAW and ROLL expos to where the craft stays on course if I ever so slightly apply YAW or Roll in Sport.

Before I changed the latter, I could barely keep a straight line in Sport.