Wookong M COG and Postion on Cinestar 8

Discussion in 'Electronics' started by Philipp Goose, Aug 28, 2012.

  1. Philipp Goose

    Philipp Goose Member

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    Hey Guy´s

    at these week i mount my Wookong M system on our Cinestar 8.
    We have some Problems with the Stability when hovering. I think we have the frong distance to the IMU center.

    On our Cinestar is an 360° Gimbal Installed so that i think the cog is under the frame.

    Can some one tell me which way is the right measure for the imu?
    Not pricesly but the way

    Thanks ahead
     
  2. Marc BRACELET

    Marc BRACELET Active Member

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    Hi Philipp, here are my settings for Wookong M on a CS6 + 3 Axis gimbal, i uplaod two pictures for unterstanding...:cool:

    GPS Location :
    Y = -12
    X = 0
    Z = -21

    IMU Location :
    Y = 0
    X = -8
    Z = -5

    So be carefull...!!! all the distances ( IMU & GPS ) should be calculated from the center of gravity.
    With 2,3 Kg Battery and DSLR with Lens, i' ve found it just below the botom center plate of the frame ( Red Line on the first picture ). For the rest The center of gravity is more or less on the center of the frame...
    I hope this help you.

    Marc.

    CG1s.jpg CG2s.jpg
     
  3. Philipp Goose

    Philipp Goose Member

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    Hi Marc,

    looks same at me, just an other position.
    i have installed an seperat plastic plate for imu reciver and the other stuff.
    First i have also -5 for Z now i have check -2 (i was a little bit better. then 0 in it will be okay. Not so good as my setting of mk finally but okay.

    But i think it could be?!?!
     
  4. Marc BRACELET

    Marc BRACELET Active Member

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    There are other things you can try, these are settings in the autopilot for jumbo Multi like CS8, it works perfectly.

    These settings give very good results in video and you will not recognize your machine after assets in wookong, everything become so smooth...

    Settings:

    Basic Gains: 175,125,175,75
    Attitude Gains: 65,65

    Give a try and tell me what you' re thinking about these sets...:cool:
     
  5. Philipp Goose

    Philipp Goose Member

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    Hi e-One Thanks for your settings!

    I have Check they quickly. It looks much better. But when i go Down with the Copter it begin to shake very much. I think more than 40° to the left And right

    I have 5.14a Beta. So you knowh what it could be??


    Greets from germany
     
  6. Marc BRACELET

    Marc BRACELET Active Member

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    It' s Totally normal, all the multirotors shake (more or less, it depend on the speed) when you go down, They are disturbed by their own airflow. And Generally no videos or photos are taken during the phase of fallen...

    I' ve forget to tell you something important too, if you CS8 weighs more than 5 or 6 kg in flight, you have to push the "Motor Idle speed " at the Maximum, this will further improve the stability of the machine and avoid overheating the motors peer or odd (Pair ou Impair in french), this setting is very important...!!!:cool:
     
  7. Philipp Goose

    Philipp Goose Member

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    Your settings work very well, also on my trainig Naza Quad

    Could you Tell me what the settings happend?
     
  8. Marc BRACELET

    Marc BRACELET Active Member

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    The "Basic Gain" ( Pitch, Roll, Yaw and Vertical ) affect the response of the machine for each selected element, for example, if you want a faster response of the yaw, increase this value ... Generally, the most heavier is the machines and the must you have to increase these gains order ti be as stable as possible. If you increase too much these gains the machine will be brutal and vibrations appears, if gains are too low the machine will be very slow to respond, and almost uncontrollable. You must find the right balance for each order.
    Now for the "Attitude Gain", they affect the reaction more or less rapid of your stick control in the RC, The more these gains are lower and the more smooth your machine will fly...65% is the lower limit, after it becomes dangerous if it is necessary to avoid an obstacle quickly.:confused:

    I hope you understand, it is not easy for me to explain in English ...:rolleyes:

    Best.
    Marc.
     
  9. Philipp Goose

    Philipp Goose Member

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    Hey guys

    I must once again turn to the forum!

    I currently still have big problems with my CS8 360 ° gimbal get stable!
    I have now fixed the frame of the IMU Positonsangaben not really play a role. Between measured-6cm for COG and the set 0cm happening on flight behavior nothing. So everything on 0cm :)

    My values ??are 175,125,175,110 that seems to me quite well and have other users Cinestar as plausible.
    As I Xoar Props 14/7 and the 5.14a software.
    All in all, the copter is only zero wind reasonably stable, but when I put a few seconds on a leave he starts to wobble. Once wind is something that goes geschaukele really begins.
    Moreover, it is so that when sinking without wind the copter begins to rock totally, so I have to interrupt the sink so that it stabilizes and I can go down further.
    The same effect is if I activate failsafe. But must always intervene otherwise the copter crash I believe!


    Maybe one of you has a tip for me what it could be
     
  10. Marc BRACELET

    Marc BRACELET Active Member

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    Could you post a little video of the "sinking" and some pictures of your bird...?
    May be it will help me to help you...:cool:
     
  11. Katya Nelhams-Wright

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    Hi there. A little off topic but can I ask which Wookong M software people are running. I am still running 5.10 and a bit nervous about upgrading due to all the discussions on forums re motor failure etc with octos and 5.12 and above.
    Thanks
    Katya
     
  12. Marc BRACELET

    Marc BRACELET Active Member

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    Hi Katya, i' m running 5.14a with no problem...but i' m with an Hexa config, i have friends with octos and WKM and no problems to...
    Best.
    Marc:cool:
     
  13. Katya Nelhams-Wright

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    Thanks
    Thanks Marc, will give it a go:)
    Katya
     
  14. Philipp Goose

    Philipp Goose Member

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    Thank´s mark for your Help. I will respect this very much!
    [​IMG]

    [​IMG]

    These are two pics of the copter and the mount of the wookong stuff.
    The Imu and all the other stuff is mounted on a plastic plate the imu is mounted in the cog (x & y axis)

    Video of the shaky effect i can take tomorrow. i ithink i will take it with my phone outside
     
  15. Philipp Goose

    Philipp Goose Member

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    Hey guy´s now i have create a small video where you can see the little shake effect!
    Sorry that i could not film the copter self. But there was no camera operator available.

    Z setting is -1 cm in the wookong tool
     
  16. Justin John

    Justin John Member

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    Hey Philipp

    Try changing your prop size. I had the same issue until i switched to 12 x 3.8 apc props
     
  17. Philipp Goose

    Philipp Goose Member

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    Hi Justin, thanks for your feedback. Could u tell me which props do you use bevor u change?
    And how big was the difference?

    Also would id be a problem to lift an 6kg kopter?
     
  18. Marc BRACELET

    Marc BRACELET Active Member

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    Hi Philipp, what is the size and power of your motors, and what is your Gimbal Stab and camera did you use for this video...i' ve noticed too a little problem of alignement betwen your IMU and GPS alignement...

    2.jpg

    It's better to put the GPS alignement the same as the IMU...but your problem do not come from there i' m almost sure...:cool:
     
  19. Philipp Goose

    Philipp Goose Member

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    Hey e-one, thaths right! Its not straight to the imu :)

    I use at these time 14/5 xoar props also 14/7 xoar props. I also check 5s Lipos but there is no different.
    Motors are qc 3328 from tiger
     
  20. Marc BRACELET

    Marc BRACELET Active Member

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    May be you should try smallers props but i think your problem came from the settings of your gimbal stab control ( The roll gain is too hight certainly ), be sure also that the balancing of your gimbal is perfectly tuned...

    This great video from Tabb will help you :cool:

     

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