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IMU calibration. How level is level?

Discussion in 'General Discussion' started by xgeek, Mar 10, 2014.

  1. xgeek

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    Location:
    London, UK, Declination -1.2
    Hi Guys,

    I understand when you do an IMU calibration you need to do it on a level surface. But how level is level? :lol: I was going to use my kitchen table and that is level as far as I can tell, but do you guys get a spirit level out and shim up the platform until 100% level?
     
  2. GMANNZ

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    Location:
    Wellington, New Zealand
    yep as good as you can do it is best ..... I do mine on a dead level marble benchtop and still check levels between the motors with spirit level as well, before starting calibrations ..... just to make sure all 4 arms are actually level above the level surface your based on.
     
  3. Big Ben

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    Nahh... Only if after such a calibration your bird doesn't fly straight or doesn't hover properly I'd consider using a level before calibrating. I just set mine on the floor when calibrating.
     
  4. GMANNZ

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    Location:
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    Yeah used to do the same, but just on main lounge table, then one day was doing some other work and noticed how out the table was when I put level on it , realised probably why phantom didnt fly straight at the time ... have only done calib once since, after changing out a motor ..... a level makes things level ;)
     
  5. MILLER4PRESIDENT2020

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    interesting, could this be the reason that my phantom never seems to fly straight and has a slight drift to the right when moving forward? Perhaps I am not calibrating it on perfectly level surface?
     
  6. ElGuano

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    That could be declination. It's a bit of a black box, but I can rotate my compass on its carbon fiber and definitely have noticed a difference when twisting it a few degrees to account for right/left drift.

    I do the IMU calibration infrequently enough where I take care to make sure it is 1) as perfectly level as I can get it within a minute, using a spirit level, and 2) not sitting on a surface with metal supports/rails underneath.