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Gimbal horizon still out!

Discussion in 'Inspire 1 Help' started by gray52, May 11, 2015.

  1. gray52

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    Had a nice few flight again today with the new firmware, my RTH height stays at the height I set even after turning everything off, but by biggest concern is that my gimbal will only give me a level horizon in certain directions when I'm yawin the inspire.

    I've done everything from imu and compass calibration but it's still out, has anyone else got this issue? If so are dji looking into it? I'm 99% happy and if dji can sort this then I will be 100% happy with everything so far, and the latest update went perfect. My horizon issue started from the firmware before this latest one. Any ideas will be great.
     
  2. infocus

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    That's exactly the problem I had with the horizon drift...it depends on the flying direction....compass and IMU calibration have been done several times. I already had three inspire gimbals to test this issue, but none of them solved the horizon problem....it's level 50% and off-level 50%....maybe there's something wrong with the inspire itself ?
     
  3. gray52

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    Glad it's not just me then. This is a firmware issue and I think it connected to the compass which is making the gimbal tilt of level when it's yawing. Hopefully dji will get this sorted. We need to do a poll to see how widespread this is.
     
  4. Soflms

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    I found this thread before I posted a new one in regards to gimbal roll for the second controller set to slave mode. I would absolutely love to see DJI give a few macro options ( as in assigning buttons to do what as we choose inside the pilot app). I for one would be thrilled if I could have my cameraman's slave controller's gimbal roll be controlled by the "camera tilt" wheel on the upper left side of the controller. That way you don't have to deal with accidental gimbal roll when following a moving object. I found the only other way to get around this is to try to control yaw and pitch on a single stick, and then control gimbal roll with the other stick which simply doesn't give the results i'm looking for.
     
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  5. m00se

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    try yawing very slowly, does it still do it?
     
  6. gray52

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    Yes it does. I think the compass is affecting it as it's off when it seems to be facing the controller, if anyone else had noticed that?
     
  7. World Media

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    One of the things we have to understand is that gimbal roll is affected totally by the start position of the top plane of the gimbal.
    We come up with this issue all the time using fluid head video tripods.
    if the plane of the top of the gimbal ( where it connects to the inspire) is not level then as you pan ( yaw) the horizon will shift.
    Now when we set off the plane iix pretty much level all around. Thats great the horizon can be set looking forward and there will be very little noticeable role as you pan/yaw.

    Remember that the moment you get into flight that primary plane becomes dynamic.
    As the Inspire pitches itself into wind to stabilise or for whatever movement in any direction the plane shifts off . this causes the horizon to be off as you pan/yaw the camera.

    You can take the camera off and simulate it, there is no physical way the camera can stay on plane for the whole of a pan/yaw unless the top part of the connection remain perfectly level.

    Hope this helps you understand the reason why it goes off horizontal.

    The greater the lean of the Inspire, the more the horizontal will be off.
     
  8. The Editor

    The Editor Moderator
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    Sorry guys.... have to disagree here - just a bit :)

    A three axis brushless gimbal dynamically adjusts in all three axis in real time irrespective of one particular plane of one axis - that's the whole point of it a being three axis gimbal.

    How efficient the correction is will be totally dependent on the Proportional-Integral-Derivative or PID tuning of the gimbal control unit or GCU coupled with the weighting factor or 'trust' value given to the gyros over and above the accelerometers. If a high trust is put into the gyros, this will take less account of the accelerometers. This is good for slow, curved movements and will allow the gimbal to retain horizon level in those sort of maneuvers. However, if too much trust is put in the gyro then it can cause horizon drift during dynamic flight. This is why both PID and trust values are so critical. If you throw into the mix the fact that the Zenmuse X3 (like the other Zenmuse offerings) are feedback looped into the flight controller you have a very delicate balance that has to be fine tuned.
    We do not know whether the algorithms within the Zenmuse are dynamically altering this 'trust' value or whether it is fixed.
    In extremely high end gimbals the trust value can be set before a shot so that if the DOP is asking for a slow curving shot the parameters can be set differently to a shot that requires very fast tracking or speedy movement.

    My two pennyworth for what it's worth.....
     
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  9. m00se

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    and in alexmos, at least you can set one RC channel to switch between 3 different profiles, and tune each one differently.
     
  10. Kilrah

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    You've got that swapped ;) it's if you put too much trust in the accels that you'll get drift in dynamic flight (large accelerations but that do not correspond to a tilt)
     
  11. gray52

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    It's still out, all I want to know and thousands of other inspire owners is when are dji going to sort it?
     
  12. The Editor

    The Editor Moderator
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    Thousands?
     
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  13. RGD

    RGD

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    So when I am flying sideways while yawing and pivoting around a subject the gimbal does not maintain a level horizon. Is the above explanation essentially what the equipment is doing.
    Is there a better way for me to get those kind of shots?
     
  14. Kilrah

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    I believe until camera/gimbal assemblies are able to do visual horizon recognition we'll just have to live with it. As The Editor says on some high end gimbals you can do some adjustments (that if you have and use take time and effort to get right before every shot), but on the I1 camera there's simply nothing that can be done as there is no user adjustment at all.
     
  15. gray52

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    It will never get sorted. It's firmware related as it was perfect for me. Dji just go off releasing stuff in the apps that no one wants and then just kill the range for a good kick in the teeth. If it was advertised with a wonky horizon and range of 300m on a good day I some how don't think we would have rushed out to get one. Strange how Dji don't advertise the range on their website anymore, I'm sure it said upto 2.5km, could change that now to 250m for me.
     
  16. Soflms

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    Exactly why I made my above comment.
     
  17. RGD

    RGD

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    I did some more experimenting with it this week end. I think when I have been doing those shots I have been in FPV. I noticed that if I do the shots in "follow mode" the gimbal does a some what reasonable job of maintaining the horizon. Its probably been pilot error on my part.
     
  18. Kilrah

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    FPV mode is precisely made to make the horizon follow your aircraft roll stick orders, so it would make sense. The feature doesn't make sense though, but whatever. It should be locked to the aircraft attitude, not stick order. And also in pitch.