Pan keeps moving/spinning at slow rate

Discussion in 'Radian' started by Thijm, Nov 6, 2012.

  1. Andy Johnson-Laird

    Andy Johnson-Laird Administrator
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    Thanks -- and just to confirm (apologies for making you repeat yourself), this is with an on-ground power up and then suspending the Cinestar so that the gear is not on the ground/table-top, right?

    I have a dim memory of seeing this behavior on my C8/3-Axis as well when I did an on-ground power up, followed by suspending it and slow pan after a few tens of seconds. I don't see that behavior in the air, though, so I didn't think much of it at the time (I was rushing to get ready for a shoot.)

    I think this is going to be a question where JohnC or Tabb will need to respond as I don't see anything abnormal with the screen shots.

    Andy.
     
  2. Thijm

    Thijm Member

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    No problem. I'm suspending it in a box-frame for easy access. makes it quite easy to rig cam's and carrying the copter.
    I don't know if these small movement are visual in the shot's. I'm currently in the change for new motors so only bench testing the Pan.
    initially i only bought the 2 axes radian for my 3 axes mount and used the aux on the roll for pan. worked quite well. after being happy with the results i ordered the 3e radian. No problem reverting to the previous config for now.

    Tfcm
     
  3. Andy Johnson-Laird

    Andy Johnson-Laird Administrator
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    The word from Those Who Know These Things is that slow drift in pan while the copter is on the ground/table is quite normal. It will not affect how you fly.

    In my case, that is certainly true. It would take a lot more than this to improve the way I fly. :rolleyes:

    Andy.
     
  4. Thijm

    Thijm Member

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    Hmmm. I cant really tell if this is true. its getting worse after a view minutes. will post a new video on monday when i get back.
     
  5. Thomas Olsen

    Thomas Olsen New Member

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    Hi ! Did you resolve this ? Have same issue on tilt.....
     
  6. John Cunningham

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    Some points on the pan when ground testing:

    1) If the mount is on the ground, the Radian does not move when the motor turns - the multirotor does. The Radian will initialise to a specific angle, but the internal IMU angle will slowly drift. This causes the motor drive which spins the multirotor. As the Radian never moves and the angle keeps drifting, the speed of the motor will increase. It only needs the IMU angle to drift a fraction of a degree for the motor to start.

    2) The Radian looks for a short period of constant output from the gyros to initialise. Normally it is on the ground and this will represent 'null'. However, if the multirotor is suspended and is slowly rotating on the suspension then this can be taken as the 'null rate' from the gyros. If this happens, the pan angle will be drifting at the rate it initialised at.

    JohnC
     

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