Alexmos 3axis

Discussion in '3 Axis Gimbal' started by Jason Herring, Sep 5, 2013.

  1. Andy Johnson-Laird

    Andy Johnson-Laird Administrator
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    Hi Kat:
    If the 3-Axi Board MOSFET doesn't extend the power handling, I'm having a hard time imagining what else it might do..... :)

    Andy.
     
  2. Katya Nelhams-Wright

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    Hi Andy.
    I meant a clever person like yourself of course or someone else:)
    So does that mean that you replace the original 3axis add on with this one or do you use this instead and does that then mean that you can run the 8000 motors?
    The website I used for X loader was
    www.russemotto.com/xloader
    and I selected the device as Mega(ATMEGA2560) and the baud rate as 115200
    That worked for me
    Thanks
    Kat
     
  3. Andy Johnson-Laird

    Andy Johnson-Laird Administrator
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    I knew it. I've been found out, dammit! :)
    We'll have to wait until Someone Else answers then because I'm just wild-ass guessing what the board does -- MOSFETs are certainly used to switch large currents, so....

    My second wild-ass guess is that you interpose this board between the Alexmos 3-Axis mother/daughter board and the motors.

    Thanks for posting that.
    Andy.
     
  4. kjetil tønnesen

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    i have setup three 3axe gimble with the alexmos 3axe board and have no problems with it at all:)
    i also use the xloader
     
  5. Jeff Patterson

    Jeff Patterson New Member

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    I bought a couple of the new 3 axis boards - Having one heck of a time with the power / worth of the expansion board -
    Running 4s, with 8017 motors on the roll and pan. Pan motor will not stay locked... a roll of more than 20 deg. and the YAW snaps from its hold.. Tried many settings, balance of all axis "seems" to be perfect - or close.
    Anyone else using the new board and getting it to work with a Heavy load ( EPIC) ?
     
  6. Ramesh Tahlan

    Ramesh Tahlan Member

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    Andy,
    some help needed.
    my two axis armbgc controller has been working fine.
    I now added the 3rd axis to my bgc 3.0
    But am a bit confused with the diagram.
    https://www.armbgc.com/product_images/uploaded_images/connection-diagramm2.jpg
    any help would be welcome.
    I want to set up the FOLLOW MODE or yaw.
    as per the diagram, the A2 (Grey wire) is the yaw output from controller to Rx Yaw channel, and also to FC Pitch channel.
    So do i need to make a Y harness..??

    Ramesh
     
  7. Andy Johnson-Laird

    Andy Johnson-Laird Administrator
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    Hi Ramesh:
    Sorry, I don't know anything about the Armbgc controller.

    Andy.
     
  8. Devin Card

    Devin Card Member

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    We have been using the new 32 bit board with 3 axis on the ground and on the heli! Love it!
     
  9. Graydon Tranquilla

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    I have the new 32bit 3 axis Alexmos BGC installed on my Cinestar 8 with tripod landing gear and a GoPro3 for testing...... It works very well in regular "heading" mode.....c/w RC override on both pitch and yaw. But when I switch it to "follow" mode so that it is supposed to follow the front of my MR whichever way it turns, it work fine during ground testing in a sling......
    But in the air it is a different story..... after a brief period of time the yaw control loses it and randomly rotates. After it settles down it seems to work again, but by then it is no longer aligned with the front of the MR....

    Seems IMHO that the "follow mode" is not fully developed for aerial work at this point.... but it could be that my PID loop tuning is not dialed in 100%. Also I think that the tripod landing gear adds a lot of angular momentum but is also very easily disturbed by wind....
     
  10. Gary McCready

    Gary McCready Active Member

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    I have an 8-bit on a DYS NEX 7 gimbal, flying a Canon EOS M. I ended up putting plastic "stops" on the yaw so it wouldn't go past 90 degrees right or left. This worked fine unless I spun (yawed) my CS6 fast, and gimbal hit the stops hard. The it would set up and oscillation that i could only get rid of by powering off. If i yaw slow, and it just only touches the stops (or not at all) it works fine.
     
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  11. Graydon Tranquilla

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    Very good information.....I am thinking that might be the best option for now as continuous rotation would not be good for the wiring to FC thru middle of Yaw axle as there is no slip ring system.

    Also I am wondering if I would be better off forgetting about the FC gimbal pitch roll outputs so as to free up a BGC PWM input so that I can make use of the BGC CMD from RC so as to change BGC profiles and/or turn the BGC motors off and on from the ground etc.?
     
  12. Gary McCready

    Gary McCready Active Member

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  13. Graydon Tranquilla

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    Thanks.... got one of those - came with my larger 5208 Yaw motor to be installed on handheld gimbal to be later transitioned on to the Cinestar8.

    In the meantime testing/proving the 32 bit 3 axis BGC with a smaller Yaw motor with axle center hole but no room for slip ring system....
    GoPro3 + BGC get moved over to my Cinestar Hex later.
     
  14. Graydon Tranquilla

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    My mistake was using a 4008 Yaw BG motor. Despite the really light camera weight, i.e., GoPro3+ Black for testing purposes, the yaw motor has to rotate the entire motor cage, tripod landing gear with the camera. That is a lot of angular momentum to manage especially in wind. Also the 4008 shaft diameter is very small leading to a lot of stress on the motor bearings such that the landing gear is now sloppy/wobbly after about a dozen test flights. Solution is to use a larger diameter higher torque BG yaw motor so I installed the 5208 and the issues seem to be under control..... but more testing required.
     

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