Occasional Issue w/ GPS Hold – Pendulum Oscillation

Discussion in 'Cinestar 6' started by Josh Wilson, Aug 24, 2013.

  1. Gary McCready

    Gary McCready Active Member

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    Nice to know I'm not the only one having more "toilet bowl" with this update than the last one! I'll adjust my GPS gain to 85%, and compass to zero and let you guys know how it goes!

    Q) Always wondered how much difference it makes having the GPS out on the arm, not in the middle of the CS6? I know with the Naza, you setup the software by exactly reassuring how many mm the sensor is off center on the X, Y and Z axis. And I know it makes a difference because I out in a positive number instead of a negative and GPS was not working correctly.
     
  2. Steve Maller

    Steve Maller UAV Grief Counselor

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    It's hard to imagine that the 8"-10" would make any difference, given the resolution of the MK GPS. I don't think it can resolve anywhere close to that. And considering the potential for EMI and other gremlins (all of which have been well-documented), the GPS is out on a boom on all the Cinestars I've ever seen (including mine).
     
  3. Andy Johnson-Laird

    Andy Johnson-Laird Administrator
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    My understanding was that moving the GPS/Navi Control board (with magnetic compass) out on to boom #1 was to avoid EMI and RFI from affecting both the compass, and reducing the sensitivity of the GPS Rx.

    Andy.
     
  4. Brad Meier

    Brad Meier Active Member
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    I'm not familiar with Naza but I bet GPS has a lot more influence on the flight with that controller. Maybe that is why they need the exact position
     
  5. Gustavo Rios

    Gustavo Rios Member

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    This new firmware besides offering altitude control very stable, landing and take off autonomously, improves the stability and smoothness of the flight?, I read a comment from a user who improved the temperature of the BL's, is this possible?, http://www.mikrokopter.us/the-software/new-2-0-firmware-check-it-out-big-changes/
    I have a spektrum DX8 and I have no more channels for use autonomous takeoff and landing, I think, or I don't know the way to do it.
    Other thing, the test's of Holguer Buss is with GPS in the center of the octocopter, this may affect the performance of those who use GPS the on the boom ?.
     
  6. Gary McCready

    Gary McCready Active Member

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    GPS hold has improved! Thanks for all the input guys!
    I took off my camera gimbal and turn the CS6 upside down on a glass table. I then loosened all the arm clamps, let things even out and re-clamped the arms (being careful to alternate the tightening among the screws to get even pressure). I then leveled the CS upright on a box, with shims. Next I made sure all motors were all perpendicular to the level copter, with a bubble level. Some were off a bit, from loosening all the arm clamps.
    I checked the FC to see if it was level, pretty close. I tried loosening and tightening some of the nylon screws holding the FC but it didn't help much. Tried a very thin nylon washer but that was actually too thick, so i left it as is. The bubble level was only about 2mm from center and the motors bolts were right on level ( I have a long 3ft bubble level).
    Next: set GPS gain to 85 (from 100) and compass correction to zero (from 64)
    Calibrated my Gyro, went out side and recalibrated my compass:
    GPS and Alt hold were MUCH better.

    Next step: Now i think I need to upgrade my radians firmware and re-balance my camera on the gimbal, as I got more twitching on the roll axis than I would like.
     
  7. Dave King

    Dave King Well-Known Member

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