Gimbal Horizon off by about 40 degrees at power up but will auto calibrate fine, every time.

[Dj Brady]

Bought a used P3A with a known issue.. It's been down once, but no visible or functional gimbal damage aside from the fact that it confidently powers on with the gimbal tilted to the right by about 40 degrees. It will function, stabilize, and pitch just fine, but holds that horizon angle. I can run the gimbal auto-calibration and after about 15 seconds, the camera rotates left/right 3 times and then calibrates to level horizon and continues stabilizing and functioning just fine.
Thoughts?

Thanks very much in advanced.

 

[Sinisalo]

try an IMU calibration on a perfectly level surface.

 

[Dj Brady]

I'll try it again. I did an advanced calibration when I first got it, but I haven't done a 'chilled' calibration.

My question is, wouldn't an IMU calibration on a surface that was 1* off, cause the gimbal default position to come up by the same 1* off?

 

[Sinisalo]

I think so, I don't think you can cheat it 40 degrees though. Try putting a thin piece of glass on top of the motor screws and then place a level on the glass. Use that method to get the surface as level as possible and then try an IMU calibration. Have you tried flying it yet?

 

[Sinisalo]

another thing you could try is a gimbal auto calibration while you are 6-7ft off the ground hovering in calm conditions. It will say the calibration has failed but you may see that it has fixed your gimbal issue.

 

[Dj Brady]

Oh yeah, I've flown the heck out of it. it flies fine and, as I said, once I complete the gimbal auto cal, it levels out and works perfectly. Unfortunately, something is persistently going back to that 40* off at power up. I have to recalibrate the gimbal every time.

I'll try the hovering gimbal calibration to see if it tricks into thinking something otherwise and performs some sort of 'reset'...

speaking of... I wonder if performing a full reset on the MC would unstick the persistent 'wrong' calibration...

 

[Dj Brady]

Figured it out... looks like the 'slippery shaft' issue is as prevalent on the gen 3 as it was on the gen 2. I popped the back cover off, and sure enough, the flat spot on the shaft was about 40* off of level camera horizon. It slipped easily, I got it straightened out, and everything seems to be good.

I assume those are designed to slip so as not to damage the assembly in case of an impact, but this slips so easily.. so be it.. I fixed it!

 

[xdub]

Figured it out... looks like the 'slippery shaft' issue is as prevalent on the gen 3 as it was on the gen 2. I popped the back cover off, and sure enough, the flat spot on the shaft was about 40* off of level camera horizon. It slipped easily, I got it straightened out, and everything seems to be good.

I assume those are designed to slip so as not to damage the assembly in case of an impact, but this slips so easily.. so be it.. I fixed it!

I'm having this same issue and I'm sure that a search for "slippery shaft" on Google is not going to get me the results I need. Can you point me to anything on this so that I can read up before taking my P3 under the knife? Thanks a ton!

 

[Dj Brady]

Where's your sense of adventure and inquiry?

It's a pretty simple process. Take out the 5 screws on the back of the horizon motor and the cover comes right off. You'll know, right away, if your camera and shaft are out of alignment. The flat notch should be level when the camera is level. If you have to adjust it, you can slip the pitch board (circuit board) off and away from the shaft, very carefully, and to the right. You'll be able to slip a pair of needlenose pliers behind the board from the left side and hold it while you re-orient the camera.

 

[Dal]

Pics?


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[Dal]

I put a gimbal guard on the landing gear. And when the bird is powered up and does its sweep it would hit it an one spot since then my camera is off 1.0 of adjustment. Is it possible that when it was hitting the shaft slipped?


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