jerky video

ruggb · Dec 27, 2019

Just realized I have jerky video on my M2Z. The video is fine other than a small side to side jerks about once per second.
Not sure how long it has been happening. I guess I have not been paying attention. It does not happen if the props are not turning. It happens with no wind. It happens on the ground or in the air at any altitude while moving or hovering. It will jerk to either side and back.

Any suggestions, please?
thanks

old man mavic · Dec 27, 2019

ruggb said:
Just realized I have jerky video on my M2Z. The video is fine other than a small side to side jerks about once per second.
Not sure how long it has been happening. I guess I have not been paying attention. It does not happen if the props are not turning. It happens with no wind. It happens on the ground or in the air at any altitude while moving or hovering. It will jerk to either side and back.

Any suggestions, please?
thanks

sounds like out of balance props and it could also be where the gimbal is suspended on the drone check to see if all is well ,put on anew set of props and see if it still does it

tyee · Dec 28, 2019

i had that problem , i was using 4k then went to 1080 problem solved

ruggb · Dec 28, 2019

Thanks for the comebacks
It might be unbalanced props, but I would think that would produce a constant repeating vibration as opposed to a periodic small jerk 1-2 seconds apart, but I can change them out and see.
The gimbal appears OK. The only anomaly I see is that, unpowered, it wants to settle about 20° to starboard. The other attitudes will stay generally where I put them.
Not sure where I have video set. I will check that. But why would 4k cause jerking? It should be even more stable if anything.

old man mavic · Dec 28, 2019

ruggb said:
Thanks for the comebacks
It might be unbalanced props, but I would think that would produce a constant repeating vibration as opposed to a periodic small jerk 1-2 seconds apart, but I can change them out and see.
The gimbal appears OK. The only anomaly I see is that, unpowered, it wants to settle about 20° to starboard. The other attitudes will stay generally where I put them.
Not sure where I have video set. I will check that. But why would 4k cause jerking? It should be even more stable if anything.

is this jerking being seen on the device screen as you fly or on your computer when you play back the video
when you video in 4k you need a powerful enough processor and video card that can play back 4k
i always record in 10-80 30Fps as my oldish computer can not handle 4k or even 2.7 when i try to play back the video it stutters runs for a second stutters and so on
because i do not post on the internet or do post production editing,then it is no problem for me

apeel · Dec 28, 2019

Perhaps post a sample of the 'jerky video'. This could help the experts (not me!) determine if it is an issue with the recording / gimbal, or if it is a playback issue.

ruggb · Dec 28, 2019

I swapped a couple props, verified it was 1080 non-HD and noticed it didn't stop shaking until about 3-5 sec AFTER the props stopped.
Guess I need more flight time to figure out everything that is happening. This video only shows the jerking on the ground with the props rotating. I will try to get more samples but maybe this is a good clue.

ruggb · Dec 28, 2019

old man mavic said:
is this jerking being seen on the device screen as you fly or on your computer when you play back the video
when you video in 4k you need a powerful enough processor and video card that can play back 4k
i always record in 10-80 30Fps as my oldish computer can not handle 4k or even 2.7 when i try to play back the video it stutters runs for a second stutters and so on
because i do not post on the internet or do post production editing,then it is no problem for me

I see it on my phone while active, I see it on the computer when playing back the video from the AC.
I am running 1080 30fps also.

old man mavic · Dec 29, 2019

ruggb said:
I see it on my phone while active, I see it on the computer when playing back the video from the AC.
I am running 1080 30fps also.

well in that case it sounds like a camera issue could be a damaged cable from the camera to the main board

ruggb · Jan 1, 2020

I reseated the gimble connector and recalibrated everything and I still have the issue.

new2mavic · Jan 2, 2020

tyee said:
i had that problem , i was using 4k then went to 1080 problem solved

You just need to upgrade your computer to one with a more powerful graphic card ....

new2mavic · Jan 2, 2020

From your observation " .... unpowered, it wants to settle about 20° to starboard ..." , I think there is some force pulling the camera to the starboard side. The gimbal tried to work against it but failed to overcome it occasionally hence the jerking. If you can find the source of that force, I think you should be able to fix it.

Why does it happen only when the motor is turning ? Well, for some reasons, the gimbal of Mavic 2 operates quite differently when the motors are spinning vs when the motors are off. There is a youtube video demonstrating this but I cannot find it now. The difference has also been seen on my M2P so I think it's by design instead of a fault. When the motor is off, the gimbal will restore the orientation of the camera no matter how much it is disturbed ( e.g. by my fingers in my experiment ). The gimbal also feels stiffer meaning that more force is needed to disturb it. Once the motor is turning, the holding force of the gimbal will became softer and if it is disturbed hard enough, it is possible for the orientation of the camer to stay slanted for the entire duration of the flight until the drone is power reset. This phenomenon occurs more easily on the yaw axis along which you have seen the jerking. I would thereforce suggest not to spend time on studying why the state of the motor has an effect. This is likely to be normal. Just focus on checking what is pulling the camera to one side when the drone is powered off. E.g. can it be due to filters mounted on the camera throwing the center of gravity off ? Try to get the camera to point to other directions ( by pressing onto the camera view on the phone and slide towards the wanted direction of movement ). Does the problem occur on some orientation only ? may be the result will provide some clues.

ruggb · Jan 3, 2020

new2mavic said:
You just need to upgrade your computer to one with a more powerful graphic card ....

NO, I have older videos that do not show jerking showing on the same computer

ruggb · Jan 3, 2020

new2mavic said:
From your observation " .... unpowered, it wants to settle about 20° to starboard ..." , I think there is some force pulling the camera to the starboard side. The gimbal tried to work against it but failed to overcome it occasionally hence the jerking. If you can find the source of that force, I think you should be able to fix it.

Thanks, I will see where that goes. The amt of jerk is in the ballpark of the displacement so that has some merit.

ruggb · Jan 3, 2020

after careful inspection i can see nothing obvious.
When I turn the AC on it goes thru the gimble procedure and is straight.
When I turn the AC off it turns about 10° to starboard on its own.
If I tilt the AC 20° to starbord the gimble will straighten up.
The filter that I have on it caused the camera to tilt down a bit, but if I take it off it is stable.
It also does not affect the side to side bias.
What would cause the side to side bias? Is there anything I can do to correct it?

bheiser1 · Jan 4, 2020

Ruggb, does your gimbal behave like this? Mine is the M2P and I noticed tonight the gimbal settles a little starboard. It straightens on powerup then goes back when I power off. If I tap it while off, it returns to the angled position.

Oh it looks like I cant upload video from my phone so maybe you can visualize what i described.

I’m not sure if I have the jerky video issue you described. I’ve had issues with it seeming rough, but have chalked that up to newbie-videographer syndrome.

new2mavic · Jan 4, 2020

Ruggb, I should have added to my comments earlier that it is perfectly normal if the force causing the gimbal to settle at a particular angle is small enough. I have a M2P and the gimbal exhibits the same phenomenon as demonstrated in this video :

I am not 100% sure but I believe it is caused by the cable linking the craft and the gimbal. In the M2P, the cable goes through the shafts of the gimbal so it's not visible from outside. The cable should be very flexible but still have some limited stiffness which makes it act like a very weak spring. On my M2P, I can get the gimbal to rest at any orientation by moving it to that position and slowly get my fingers off the gimbal. That means the friction of the gimbal bearings alone is sufficient to counteract the spring force of the cable. If yours is like that also, it should not be the cause of the problem.

ruggb · Jan 4, 2020

@beheiser1 @new2mavic
Yes, it acts exactly as beheiser1 describes. I cannot set it at any other position and have it stay there. It will always move to about 10° starboard. It takes a tilt of the AC of about 20° starboard to have it center. I can set the other attitude positions and they will stay where set (without a filter). If I move the gimble to port it is very determined to move back to 20° Stb. It does not behave like new2mavic's video, as it will not stay in any other position unless I counter the force by tilting the AC.

new2mavic · Jan 4, 2020

ruggb said:
@beheiser1 @new2mavic
It takes a tilt of the AC of about 20° starboard to have it center.

To test whether the stubbornness to point off center is causing the jerking, you may try centering it first by tilting the craft by 20 degree as you said, start the motors with the propellers taken off, take a video and see if the jerking is still there.

ruggb · Jan 5, 2020

I thought I tried to start the motors in the past with the props off and it would not run for more than a second or two. I did think about doing that with the props on since I don't need it to takeoff. I guess I will work on that.