Gimbal moves without input

[mnpaslay]

I posted this issue on another thread but it got hi-jacked. Trying to confirm an issue that I think occurs on all Mavic Minis (so I know if I should exchange or wait for firmware fix). Please don’t speculate on the cause until you try the below maneuver.

1. In P mode with light to no wind fly up to 100 feet.
2. Point the gimbal straight down (-90).
3. Fly forward slightly. Try maybe 10 short forward inputs.
4. Fly up slightly, again try mode 10 short ascends.
5. Is your gimbal still straight down?

When I do the above my gimbal moves to maybe -80. Below is a link to a video.

Right around 12 seconds the gimbal moves up with no input from me and then I correct around 18 seconds.

Latest firmware and app, iOS. iPhone X.

 

[Matriculated01]

This happens to me as well. Didn’t know what to think of it, figured it must be something about the programming. I can’t remember the exact maneuver I did, but I remember I had the gimbal 90 degrees down and saw it pop up slightly with no input on the gimbal roller.

 

[Matriculated01]

It just did it again a few minutes ago. Gimbal pointed straight down at 90 degrees. When drone is moved forward gimbal pops slightly up by itself. Does anyone know why it does this and is it normal?

 

[blakamin]

I'd be guessing that when the mini is moving the gimbal is moving to compensate for that angle of attack (or else it would start looking backwards) but then it doesn't correct itself when you stop suddenly.

 

[raymacke]

I too have had it happen.

 

[Matriculated01]

I'd be guessing that when the mini is moving the gimbal is moving to compensate for that angle of attack (or else it would start looking backwards) but then it doesn't correct itself when you stop suddenly.

That makes sense. Can we get some more input from other MM owners? If it’s happening to everyone then that’s probably the explanation and it’s meant to do that.

 

[mnpaslay]

I’ve hand Phantom 3 and 4 prior, it is not normal. Why would the gimbal move without user input...it’s a bug, just need to determine if it affects everyone or not...

 

[Matriculated01]

I’ve hand Phantom 3 and 4 prior, it is not normal. Why would the gimbal move without user input...it’s a bug, just need to determine if it affects everyone or not...

Not enough data to know for sure if it’s a bug or not. @blakamin provided a plausible explanation. I haven’t and don’t own any other drones, we’re talking about the MM here. Just because something is or isn’t the case on one drone doesn’t mean it’ll be identical on the next or all drones. If you would like to be helpful, it would be nice to know if your MM (if you own one) does the same.

 

[mnpaslay]

Not enough data to know for sure if it’s a bug or not. @blakamin provided a plausible explanation. I haven’t and don’t own any other drones, we’re talking about the MM here. Just because something is or isn’t the case on one drone doesn’t mean it’ll be identical on the next or all drones. If you would like to be helpful, it would be nice to know if your MM (if you own one) does the same.

I started the thread...if you set it to -90 it should stay there until you change it...

 

[Matriculated01]

I started the thread...if you set it to -90 it should stay there until you change it...

Oh ?.
Technically speaking, if you have the cam at 90 degrees down and move forward with the gimbal stationary, it is no longer at 90 degrees... it will go higher. See the issue? The point of the gimbal is to stabilize the cam at the degree angle you want, right? By remaining at 90 degrees (meaning locked in the 90 degree position) the cam would be pointed above 90 degrees. I don’t know the answer here and you could be right, but food for thought.

 

[Matriculated01]

Maybe the MM is doing what it’s supposed to do, just in a glitchy way, meaning yes it’s a bug but easily fixable via firmware update.

Question for old timers who knows this type of stuff: on your other drones (M2P, Air, whatever) does the gimbal compensate for movement when your cam is pointed directly 90 degrees down? Meaning does it decrease the attack angle when moving forward or does your field of view skew backwards? What’s the standard on drones?

 

[mnpaslay]

You can see the gimbal jump up 4-5 times in the video...the only gimbal commands where downward and none of the maneuvers were aggressive...

 

[mnpaslay]

Maybe the MM is doing what it’s supposed to do, just in a glitchy way, meaning yes it’s a bug but easily fixable via firmware update.

Question for old timers who knows this type of stuff: on your other drones (M2P, Air, whatever) does the gimbal compensate for movement when your cam is pointed directly 90 degrees down? Meaning does it decrease the attack angle when moving forward or does your field of view skew backwards? What’s the standard on drones?

That’s what I was telling you, I had prior phantom 3 and phantom 4, the standard is it keeps the view straight down...

Also the -90 setting I mentioned is the setting, the actual gimbal angle will vary to accommodate the -90 setting...depending on flight/wind/etc...

I believe it will be solved with new firmware...

 

[DanMan32]

M2 has the opposite problem. If gimbal is straight ahead and you move quickly in sport mode, it moves down about 10 degrees.

It all probably has to do with gimbal hitting it's limits when AC is tilting forward (for M2 issue) or tilting backwards for braking (for MM issue).

 

[mnpaslay]

M2 has the opposite problem. If gimbal is straight ahead and you move quickly in sport mode, it moves down about 10 degrees.

It all probably has to do with gimbal hitting it's limits when AC is tilting forward (for M2 issue) or tilting backwards for braking (for MM issue).

Totally different. If you are at 0 and you go forward fast it can hit the limit because the drone is nose down and the camera can only go up so much (maybe 10-20 degrees). I would expect it to return when you hover. In this case it is at -90 straight down and when you go forward the nose of the drone goes down and you have almost 120 degrees of gimbal to compensate before you hit the limits...

 

[raymacke]

Here is what mine looked like -

 

[nlimchua]

I run a UAV repair business in NJ where I do a lot of component level microsoldering work. Yes, I have seen this symptom (on MPs). It is an issue with the gimbal's mainboard that does not respond to firmware upgrade or downgrades; gimbal re-cal or IMU cal. It is a very annoying problem and it very looks like a chipset issue.
At this point, the only solution I have is a mainboard replacement.
Down the road, if I discover other solutions, I will post it.

 

[DanMan32]

Totally different. If you are at 0 and you go forward fast it can hit the limit because the drone is nose down and the camera can only go up so much (maybe 10-20 degrees). I would expect it to return when you hover. In this case it is at -90 straight down and when you go forward the nose of the drone goes down and you have almost 120 degrees of gimbal to compensate before you hit the limits...

You didn't read my entire post. For M2, it is as you described. On tilting forward at max speed, gimbal hits it's upper limit and so tilts down.

On MM, the issue is probably that it hits the downward limit upon AC tilting backwards for sudden braking. Same problem, just opposite direction.

 

[scro]

For me it seems to depend what flight mode is being used. When in C mode the gimbal keeps looking straight down, even when flying forward or backward at full speed. On P mode the gimbal pops back to about -80deg when braking or flying backwards, and on S mode it pops back to -70deg or so after some full throttle fwd/backward flying. It's not ideal and the hardware should be capable of maintaining a direct down view in C and P modes. In S mode theres not enough gimbal travel available during backwards flight or braking. The gimbal would needto look down and backwards under the drone body, up to -120deg, to compensate for aircraft tilt, but the end stop is at -110deg

 

[mnpaslay]

I can get the issue to occur with just a slight ascend, not forward or backward input. It does seem to required user input on the sticks, so I think it is software related to trying to preemptive move gimbal for steady shot. To test the theory or it being related to exceeding the stops you can try this:

1. Power up mavic mini and controller
2. Do not lift off, just point the gimbal straight down.
3. Move the mavic mini around manually (holding it, props not spinning). I can not get the gimbal to move off the -90 setting. If I exceed the angles it can handle the picture tilts but when I return it to normal level flight it goes back to -90.