A New Not-New Gimbal Issue

Marich · Feb 21, 2016

Yo folks!
I remember reading about Solo gimbals pointing right. I never had that problem, so didn't really read about it in detail.
Wellll... after the new update my gimbal - three guesses! Yep, points right. Not just a couple of degrees either, as the right leg and headlight are in most shots.
Now, I know I've read that 3DR resolved the problem, but don't remember whether it was a software correction or just newer gimbals not having the problem - but, dagnabbit all, mine has been perfectly fine since I got it last summer! Tons of pointing-straight-ahead flight time with video evidence.
I never noticed it until I was playing around with follow me: I couldn't center myself, I'm always off to the left of the frame or out of it entirely.
Mechanically the gimbal works as perfectly as ever. But on power up, it very determinedly swings that GoPro right and stays there, just as if that's where it belongs. Major league annoying, lemme tellya.
I did all corrective calibrations including the sticks. Finally I emailed 3DR and found that to get things sorted out I'd have to pop both the gimbal and Solo in the mail to them. But I don't wanna be Solo-less that long! Spring's right around the corner! Think I'm gonna cwyyy -
KER-SLAPPO!!!
Thanks, I feel all better now.
Anyway, I searched the forum and can't really find a solution. Seems as if the problem kind of just went away. But I know someone here's got the story!
So... help!

SteveReno · Feb 22, 2016

Been a member here for a while, never read about Solo pointing right, more then a couple of degrees?
Has it ever crashed? Hard landing? There might be something bent?

If i was you, send it in, & ask to expedite the inspection.

Marich · Feb 22, 2016

Nope, never crashed or even landed roughly.
It's a mystery.

Ian [P13] · Feb 22, 2016

It will point forward in flight. The gimbal uses the nav data from the compass and GPS to direct itself, this is why its direction isn't that consistent when simply powered on but not moving. That's from 3DR.

There was talk about deliberately offsetting the gimbal in the code, but this never happened.

If you have any issues in flight, do a compass and level calibration, then contact support if a problem persists.

Lance · Feb 22, 2016

My gimbal was replaced by 3DR for that reason and also because the motor was making some weird noises. It's a problem 3DR is aware of and don't let anyone tell you it's supposed to be offset from center because it's not.

Ian [P13] · Feb 22, 2016

Lance said:
My gimbal was replaced by 3DR for that reason and also because the motor was making some weird noises. It's a problem 3DR is aware of and don't let anyone tell you it's supposed to be offset from center because it's not.

100% incorrect. I've discussed this with 3DR specifically in the past, I've attached the post by Jason Short of 3DR below which was posted on the 3DR Solo Mod Club Facebook group.

3DR often will RMA simply to double check (for example you said you had motor noise) and in part it was due to misinformation on forums.

The gimbal uses an EKF which needs navigation data, on the ground, not moving it's not getting any data.

Lance · Feb 22, 2016

Ian [P13] said:
100% incorrect. I've discussed this with 3DR specifically in the past, I've attached the post by Jason Short of 3DR below which was posted on the 3DR Solo Mod Club Facebook group.

3DR often will RMA simply to double check (for example you said you had motor noise) and in part it was due to misinformation on forums.

The gimbal uses an EKF which needs navigation data, on the ground, not moving it's not getting any data.

That's all great but like the op states, the gimbal was offset when in flight. Same issue I was having.

Lance · Feb 22, 2016

And maybe you can tell me why 3DR replaced my gimbal if it was supposed to make a motor noise and be offset. The new one did not have these issues.

Ian [P13] · Feb 22, 2016

Lance said:
That's all great but like the op states, the gimbal was offset when in flight. Same issue I was having.

Flight is a different matter, if a compass and level calibration don't sort that it's one for support. I'm so used to people raising the issue on the ground and the comment "But on power up, it very determinedly swings that GoPro right and stays there, just as if that's where it belongs" that I wasn't convinced...

CanadianSolo · Feb 22, 2016

When solo is ready for a nap... do you put the foam padding back into gimbal? Or did you throw it away? I kept mine and use it as the sticker on the foam said to put it back..... I cut mine out a little bit so that it slides in and out easier over the gimbals weights. Maybe it got damaged putting it in and out of the case?

Ian [P13] · Feb 22, 2016

Lance said:
And maybe you can tell me why 3DR replaced my gimbal if it was supposed to make a motor noise and be offset. The new one did not have these issues.

There's always some noise from the gimbal, and if you're looking for a problem you'll be more likely to think it's a problem. Like I say 3DR give the benefit of the doubt and would change it anyway if there was a complaint.

As you can see from the comment made by the hardware guys at 3DR sometimes on power up it may point straight, it may not, means nothing either way as the high torque mode doesn't activate until in flight at which point the EKF uses the compass and GPS data to work out which way is forward. So this is why a compass calibration can have an effect.

SurfnSkate81 · Feb 22, 2016

Always use the foam. I take it out right before I power up Solo and put back as soon as I power down.

Sent from my iPhone using Tapatalk

Ian [P13] · Feb 22, 2016

CanadianSolo said:
When solo is ready for a nap... do you put the foam padding back into gimbal? Or did you throw it away? I kept mine and use it as the sticker on the foam said to put it back..... I cut mine out a little bit so that it slides in and out easier over the gimbals weights. Maybe it got damaged putting it in and out of the case?

From what I've heard it takes a hard landing to knock the tune out from the gimbal so just packing and unpacking into a backpack shouldn't ever be a problem.

Marich · Feb 22, 2016

Ian [P13] said:
Flight is a different matter, if a compass and level calibration don't sort that it's one for support. I'm so used to people raising the issue on the ground and the comment "But on power up, it very determinedly swings that GoPro right and stays there, just as if that's where it belongs" that I wasn't convinced...

I'm not sure I get that comment. Are you suggesting there's something fishy about my verbiage?
I'm a writer, I get creative with my posts. The truth of what I say, however, remains.
Think I'll take a videotape of the gimbal when I get home and just post 'er right here.
I've done all calibrations, including the sticks. I've re-checked the gimbal installation 7 times. 3DR knows this - why else would I be told it may need to come in?
In flight, the gimbal doesn't change position one iota. That's why my smart shots aren't aligned properly and why the right leg and light is in the shot.
During the time between the last as-intended functioning of the gimbal and the off-center "new normal", my Solo has been through all this:
Put in backpack.
Removed from backpack.
Doesn't seem apocalyptically traumatic.

Ian [P13] · Feb 22, 2016

Marich said:
I'm not sure I get that comment. Are you suggesting there's something fishy about my verbiage?
I'm a writer, I get creative with my posts. The truth of what I say, however, remains.
Think I'll take a videotape of the gimbal when I get home and just post 'er right here.

You said within your post you were looking at it, at "power up" which isn't an indicator of an issue, hence my confusion. Compass calibrate, then fly, then check the gimbal in flight, if there's still an issue then it's one for support.

RichWest · Feb 22, 2016

If I may offer something....since you want 3DR to be the last resort.

It all makes sense what Ian said regarding EKF, Solo's compass and whatever needing flight to orient the gimbal properly. When my bird starts the gimbal/camera tends to point off to the right slightly. Once in flight everything seems to correct. I've tested this by picking up the powered bird and moving the bird in a yaw, pitch and roll simulation. This action does set things straight in my case.

I know you checked several times your gimbal install. But it is possible for the factory HDMI cable to either push or pull on the gimbal once everything is assembled. The pulling or pushing will rotate the gimbal mount (top plate). In your case it sounds like the HDMI cable is pushing the gimbal top plate. Motor noise is indicating an effort other than the neutral orientation, i.e. dead center forward.

You can verify a neutrally oriented gimbal by examining the V-notch plate attached to the gimbal's stem, the portion that passes through the, as 3DR calls it, gimbal's beauty plate, which is the plate that secures the gimbal assembly to the bird. This V plate does not rotate with the yaw motor, as it is stationary on the stem.

Flipping the bird over on it's back onto a table, while powered off, you should be able to see if the V-Notch is bisecting the bird's center-line. To whatever degree your camera is off, you'd see a similar offset in the V-notch's orientation, if the HDMI cable is the source of the offsetting issue.

Are you experiencing more than normal micro vibes or jello effects from your video? This would be another indicator of mechanical interference by not allowing the gimbal to float within the assembly.

RichWest · Feb 22, 2016

Picture is worth a thousand(s) words....quick sketch

Marich · Feb 22, 2016

Well now, this is weird...
I thought I'd check the gimbal wiring again and noticed something I'd completely missed until now.
How? For how long? I dunno. Even after I put things back in order the gimbal still points right, but I haven't flown it yet. Maybe this'll fix things.
I wonder how many times this has happened?