Camera gimbal issues...! HELP!

flyingclint · Mar 13, 2015

So I'm having issues with my gimbal not staying level during flight. Most of the time I take off and it is tilted about 5-6 degrees to the right. So I use the app camera gimbal adjustment to tilt it back to the left, but during flying sometimes it slowly either drifts back to the right or might drift opposite to the left and then I have to reset it again...! It's super frustrating and is messing up my shots obviously cause the horizon or other things are slightly tilted in the frame and then look scewed! I've done camera gimbal calibrations numerous times and it doesn't help. Anyone have an idea what could be causing this and how to fix it? Could it perhaps be an issue with the current firmware I'm running, (I'm on the firmware version right before the newest one that is out right now???)

Thanks!

-Clint

Kilrah · Mar 14, 2015

There's a whole thread about it that's been active in the past week, do a little search. Did you do a gimbal calibration?

sdjackaerial · Mar 14, 2015

Kilrah said:
There's a whole thread about it that's been active in the past week, do a little search. Did you do a gimbal calibration?

He says " I've done camera gimbal calibrations numerous times and it doesn't help. "

Quadpilot · Mar 14, 2015

flyingclint said:
So I'm having issues with my gimbal not staying level during flight. Most of the time I take off and it is tilted about 5-6 degrees to the right. So I use the app camera gimbal adjustment to tilt it back to the left, but during flying sometimes it slowly either drifts back to the right or might drift opposite to the left and then I have to reset it again...! It's super frustrating and is messing up my shots obviously cause the horizon or other things are slightly tilted in the frame and then look scewed! I've done camera gimbal calibrations numerous times and it doesn't help. Anyone have an idea what could be causing this and how to fix it? Could it perhaps be an issue with the current firmware I'm running, (I'm on the firmware version right before the newest one that is out right now???)

Thanks!

-Clint

Sounds to me like what you need to do is an IMU calibration. The IMU needs to know what level flight is before it can tell the gimbal to hold level horizon.

Mazz · Mar 14, 2015

Agreed with quad pilot. This was happening to me as well. Calibrated IMU and issue went away immediately.

flyingclint · Mar 14, 2015

Interesting! I kept asking awhile back about the importance of doing an IMU Cal. Mostly due to flight errors and such, but mostly everyone kept telling of my numbers were in the safe zones like .01 to -.01 and such that it was fine. These are always the numbers I see in the IMU sensor, so I haven't bothered to do an IMU cal. I guess I need to do one now.
So is it literally as simple as going into the app, selecting sensors> IMU > calibration and letting it sit there and do its thing???
How crazy should I be about making sure the ground I have it on is perfectly level? In other words if I do it on my kitchen wood floor, is that good enough and is doing it inside ok to do??? Should the camera be attached when I do the Cal, or do it without it???

sirnikolas · Mar 14, 2015

IMU calibration is best done on a dead level surface and away from strong magnetic interference, such as magnetite, parking structures, and steel reinforcements underground. Cellular phones and massive metal objects can also interfere.
Same goes for compass calibration.

flyingclint · Mar 14, 2015

sirnikolas said:
IMU calibration is best done on a dead level surface and away from strong magnetic interference, such as magnetite, parking structures, and steel reinforcements underground. Cellular phones and massive metal objects can also interfere.
Same goes for compass calibration.

Yes, I am fully up to speed on compass calibrations, (do them all the time) but have never done an IMU cal.
I wasn't aware that metal, steel, phones, etc... Could interfere with the IMU cal. Like it does with the compass cal. I thought it was mostly calibrating the sensors that deal with the gyroscope, the accelerometer, and such which wouldn't be affected by these things that affect the compass. Can anyone else confirm that these things will have adverse affect of the IMU like they do on the compass??? Does this mean I shouldn't do the IMU cal inside my house and if not where is a better location that would be outside that would guarantee the surface is perfectly level???

sirnikolas · Mar 14, 2015

I stand corrected, all of the above is reflected only on compass calibration. I breezed through the manual and misread what I was reading. (1 am Melbourne time) But a dead level surface is a must for IMU calibration. I usually calibrate the IMU on my kitchen bench as it's dead level. I checked it with a 1 meter spirit level.

flyingclint · Mar 14, 2015

Ok. So then I am assuming doing an IMU cal on my kitchen floor is probably a good option then! Thanks!

DCGOO · Mar 14, 2015

flyingclint said:
Ok. So then I am assuming doing an IMU cal on my kitchen floor is probably a good option then! Thanks!

If your floor is dead level, yes. But check it in both directions. I'd really be surprised if your house is precisely level. You may have to adjust it with a few sheets of paper under one or more of the landing skids.

flyingclint · Mar 14, 2015

Ohh. Wow! So yall are saying its that finite of having to be dead level? So I would use a bubble level on the arms of the I1 to make sure it is dead level before doing the IMU cal???

Michael Dicker · Mar 14, 2015

More precise is better.

DCGOO · Mar 14, 2015

flyingclint said:
Ohh. Wow! So yall are saying its that finite of having to be dead level? So I would use a bubble level on the arms of the I1 to make sure it is dead level before doing the IMU cal???

Level = level. I set mine up on my desk, and carefully shimmed two of the legs, until it was dead on.

flyingclint · Mar 14, 2015

Ok, I am in the middle of cal right now. Set it up on my dining room floor and shimmed the feet using paper and a bubble level. Everything looked dead on. I used a measuring stick to go across from left to right side in the back to get the side leveled and then stuck the measuring stick from front motor to back motor to get the front to back leveled. It said "calibration finished" at the end and showed 100% I suppose this means it went fine? Before the IMU cal the numbers were reading x= -.01 y=-.00 z=.00 mod=.01
Now they all read .00
Is this good???

Michael Dicker · Mar 14, 2015

Very!

flyingclint · Mar 14, 2015

On a totally different note, if you go into gain settings what does adjusting the gyro gain do? I have changed my ATTI gain and yaw and I like the way they are reacting now, but what does the gyro gain adjustment change in flight???

The Editor · Mar 14, 2015

flyingclint said:
On a totally different note, if you go into gain settings what does adjusting the gyro gain do? I have changed my ATTI gain and yaw and I like the way they are reacting now, but what does the gyro gain adjustment change in flight???

I haven't gone there as I have only altered my attitude gain and throttle curve but I would guess much the same as gyro gain on a CP heli. The contra rotating blades on a quad cause and counteract rotational movement (yaw) and the gyro gain will influence the speed/sensitivity of angular corrections to yaw.
In reality, it's a little more complex than that since the mems gyros are 3 dimensional.

Arsh · Jun 7, 2015

I'm also having this issue. Did an IMU calibration today on a level table, the values are all where they need to be. Without moving the bird I did an gimbal calibration but when I flew it after that the horizon was still tilted. While it was in the air I did some gimbal adjustments but it doesn't hold for long.

Any ideas?

Michael Dicker · Jun 8, 2015

Arsh said:
I'm also having this issue. Did an IMU calibration today on a level table, the values are all where they need to be. Without moving the bird I did an gimbal calibration but when I flew it after that the horizon was still tilted. While it was in the air I did some gimbal adjustments but it doesn't hold for long.

Any ideas?

Did you get close to 1.00?
IMU should be between 1.00 +/- 0.01

This is really important.