Welcome to PhantomPilots.com

Sign up for a weekly email of the latest drone news & information

How to fix a vibrating / shaking / crazy P2V+ camera gimbal

Discussion in 'Phantom 2 Vision + Discussion' started by yotamkasam, Jul 16, 2014.

  1. yotamkasam

    Joined:
    Jun 3, 2014
    Messages:
    26
    Likes Received:
    2
    Location:
    Israel
    It appears that after a crash or even a modest hit the camera may get life of its own. As shown in the link bellow, the gimbal starts to vibrate and shake with no apparent reason and the remote has no control over it. Sometimes it will get fixed by itself and you can fly, but you should expect it to go wild again and need to fix the gimbal.

    http://ninoransenberg.com/2014/07/16/phantom-2-vision-camera-gimbal-has-life-of-its-own/

    What may look like control / firmware issue is a simple mechanical failure of the gimbal's X axle which upon good side impact will get loose from its base. As shown in image A below, the axle marked green should be firmly snagged in the yellow marked bore.



    Once the axle is released from its base, the only thing that holds the motor in place is the round magnet of the brushless motor. It will hold it with enough strength and you may have no clue that it is broken. It also may work for some time after the impact but once the axle turns freely it will misalign the camera position and the trimmer-potentiometer located on the other side of the motor will not read correct physical position of the camera.

    Image B shows a post impact trimmer and its misalignment with the camera on the X-axle. The trimmer is the feedback mechanism of the micro-controller which reads the trimmer resistance based on its angular position (like a volume button) and assumes the camera is aligned with it. When the reading is extreme to one of the ends, the controller tries to fix it and starts bouncing quite radically.



    The proper alignment of the trimmer is shown in the image C, note the blue lines, the trimmer flat notch should be parallel with the flat edge of the PCB. Don’t worry about slight misalignment, the gimbal can work with that.



    To fix the problem I remounted the axle using extreme strength treads locker (Loctite or similar) and clamped the motor in place overnight to allow the bond to fully cure.
    Not knowing in advance what I am dealing with, I took the camera off the quad but you don’t have to, you can do the work leaving the gimbal attached to the body. If you do take it apart, you can use plastic wire fasteners instead of the anti-drop pins which you have to cut during disassembly.



    A test flight I did today gave very good results, no evidence of the problem. However, I am not sure how long this will hold, the axle might be released again and I will have to repeat the fix. This is why I used soft Loctite and not hard metal bonding formulas that will make it difficult to remove residues in due time.

    As for DJI, it seems to me they are aware of the problem but will not tell you how to fix it, they will however ask you t ship it back.
     

    Attached Files:

    • B.JPG
      B.JPG
      File size:
      273 KB
      Views:
      20,894
    • A.JPG
      A.JPG
      File size:
      297.6 KB
      Views:
      19,857
    • C.JPG
      C.JPG
      File size:
      355.9 KB
      Views:
      19,604
    • D.JPG
      D.JPG
      File size:
      339.9 KB
      Views:
      18,935
    KristoX and Sky Media Drones like this.
  2. happydays

    Joined:
    Jul 5, 2013
    Messages:
    1,858
    Likes Received:
    663
    Location:
    Warrenpoint, Ireland
    Re: How to fix a vibrating / shaking / crazy P2V+ camera gim

    Good call. Well explained.
     
  3. gverila

    Joined:
    Jul 2, 2014
    Messages:
    21
    Likes Received:
    0
    Re: How to fix a vibrating / shaking / crazy P2V+ camera gim

    Thank you. It's good to know if I need that solution in a distance future :) I just hope that super glue will bond this parts for a long time. For that kind of damage it is not acceptable to buy a new (over priced) gimbal and camera kit.
     
  4. dezunka

    Joined:
    May 27, 2014
    Messages:
    51
    Likes Received:
    0
    Re: How to fix a vibrating / shaking / crazy P2V+ camera gim

    Good job on your explanation and photos! I wish that DJI would have made the pin through the potentiometer about 5 mm longer and add a threaded end with a lock nut to hold it in place. This way, if the camera becomes off alignment with the horizon, you could simply loosen the lock nut, reset the camera to the horizon and tighten the nut. The fact that the pin is pressed into the aluminum housing and that is the only thing holding the camera on the X-axis is just plain silly!
     
  5. slothead

    Joined:
    Jun 14, 2014
    Messages:
    485
    Likes Received:
    2
    Location:
    Frederick, MD, USA
    Re: How to fix a vibrating / shaking / crazy P2V+ camera gim

    I haven't looked closely at mine (it's not shaking yet), but is there not a way for us to add our own threaded fastener in place of the pin/tube?
     
  6. Dirty Bird

    Joined:
    Apr 15, 2014
    Messages:
    0
    Likes Received:
    9
    Location:
    Glen Burnie, MD - USA
    Re: How to fix a vibrating / shaking / crazy P2V+ camera gim

    I would think a small redesign would greatly alleviate this issue. Adding splines to the press-fit shafts, and matching groves in their mating surfaces.
     
  7. yotamkasam

    Joined:
    Jun 3, 2014
    Messages:
    26
    Likes Received:
    2
    Location:
    Israel
    Re: How to fix a vibrating / shaking / crazy P2V+ camera gim

    I wouldn't have super glue or similar near this equipment.
     
  8. gverila

    Joined:
    Jul 2, 2014
    Messages:
    21
    Likes Received:
    0
    Re: How to fix a vibrating / shaking / crazy P2V+ camera gim

    Ups, sorry. You just use a treads locker, but it is gonna be enough?
     
  9. Fritz

    Joined:
    Jul 1, 2014
    Messages:
    62
    Likes Received:
    0
    Location:
    New Jersey
    Re: How to fix a vibrating / shaking / crazy P2V+ camera gim

    Very informative post and pictures. Now if we could just buy the ribbon cables...
     
  10. fastsmiles

    Joined:
    Apr 22, 2014
    Messages:
    844
    Likes Received:
    130
    Location:
    Fort Worth, Tx
    Re: How to fix a vibrating / shaking / crazy P2V+ camera gim

    Excellent post and clear explanation, thanks :D
     
  11. yotamkasam

    Joined:
    Jun 3, 2014
    Messages:
    26
    Likes Received:
    2
    Location:
    Israel
    Re: How to fix a vibrating / shaking / crazy P2V+ camera gim

    So far so good, but I am not sure how long it will hold. Obviously this material is not as strong as it should be and it may add some flex where we don't want it, but I couldn't find a better way. Maybe others will.
     
  12. npalen

    Joined:
    Mar 12, 2014
    Messages:
    532
    Likes Received:
    8
    Location:
    Kansas
    Re: How to fix a vibrating / shaking / crazy P2V+ camera gim

    Did your ribbon cable survive this trauma? Did you have to peel the ribbon loose from the vertical surface or did that happen inadvertently?
     
  13. yotamkasam

    Joined:
    Jun 3, 2014
    Messages:
    26
    Likes Received:
    2
    Location:
    Israel
    Re: How to fix a vibrating / shaking / crazy P2V+ camera gim

    The black ribbon survived, there was no need to touch it.
    However, the treads locker is too soft and while holding the parts in place it allows too much flex. Need to find better formula.
     
  14. npalen

    Joined:
    Mar 12, 2014
    Messages:
    532
    Likes Received:
    8
    Location:
    Kansas
    Re: How to fix a vibrating / shaking / crazy P2V+ camera gim

    I would think that the red Loctite or Permatex would be a very strong bond requiring heat to loosen it.

    http://www.amazon.com/Permatex-27100-Hi ... rmatex+red

    Not sure if a person would ever need to disassemble the joint but if so a soldering iron on the end of the shaft might do the trick without damaging anything.
    My camera mount has never come completely loose from the shaft but it has turned on the shaft throwing the camera out of level. I might end up disassembling it to use the red grade of Loctite if the green penetrating grade doesn't hold long term. I would rather not disassemble, however, for fear of damaging the fragile ribbon cable.
     
  15. cahutch

    Joined:
    Jul 8, 2014
    Messages:
    558
    Likes Received:
    4
    Location:
    Sonoma County, CA
    Re: How to fix a vibrating / shaking / crazy P2V+ camera gim

    I would think you wouldn't want to secure it too well. You want a predictable point of failure.
    Better to have the shaft come lose again, which you know how to fix, than to have the shaft hold but bend or break off under stress.
    Also consider when/if it does come lose again, you'll need to be able to clean off the excess adhesive from the last repair.

    The black ring on the inside circumference of the motor shaft is a magnet. It looks like (I assume) it's the plastic flexible kind of magnet that may melt under heat.
    Even if it's not, magnets can lose their charge if they get too hot.
    So soldering or using heat to remove red locktite might be a problem.

    Super Glue would probably leave vapor deposits all around the inside of the motor as it cures.
    A strong epoxy might work, but might be too strong for a predictable point of failure and difficult to remove if you need to repair again.

    What would be best is if the shaft and socket had a slot or D shape to align it and prevent rotation.
     
  16. npalen

    Joined:
    Mar 12, 2014
    Messages:
    532
    Likes Received:
    8
    Location:
    Kansas
    Re: How to fix a vibrating / shaking / crazy P2V+ camera gim

    A drilled and tapped hole into the end of the shaft would allow for a miniature capscrew and washer for retention. The screw could perhaps be tensioned enough to allow some slippage in the event of a traumatic event. (read crash)
    I agree that a "D" shaped shaft with setscrew would have been a good design as they did in the vertical (yaw) axis.

    EDIT: http://www.djiguys.com/Forum/viewtopic.php?f=49&t=5158
    This is a somewhat similar thread where a forum user talks about having replacement ribbon cables made for sale.
     
  17. Pepijn1908

    Joined:
    Apr 23, 2014
    Messages:
    13
    Likes Received:
    0
    Re: How to fix a vibrating / shaking / crazy P2V+ camera gim

    Hi,

    I just took my broken gimbal apart. It seems that I have another revision. The tilt motor is in the other way around. The camera is mounted to the shaft and the magnets are on the other side. The camera is connected to the shaft with a screw that runs trough te shaft. So no magnets or glue involved. No chance of it coming off at a crash.

    That said, I do have your problem but I can't see the misalignment shown in your images.
     
  18. dezunka

    Joined:
    May 27, 2014
    Messages:
    51
    Likes Received:
    0
    Re: How to fix a vibrating / shaking / crazy P2V+ camera gim

    Pepijn1908 - I'd love to see a picture of your configuration. I think we are talking about different motors. The tilt motor has the silver cap on the end of the magnets. This is the motor that allows the camera to tilt straight down and back up to the horizon. We aren't talking about that motor, we are talking about the motor that is on the rear of the camera assembly which stabilizes the horizontal axis of the camera to keep it level with the horizon.

    If you can pull this motor apart (in other words - if the magnets are all that's holding your camera to the rear down shaft) then this is your problem.

    yotamkasam - I know you think it might be too strong but I am telling you - a small dab of JP Weld epoxy does the trick. In all honesty, if you crash this thing too many times the camera is bound to get destroyed at some point anyway. If the thread lock isn't holding then what's the point?! JB Weld!!
     

    Attached Files:

  19. Pepijn1908

    Joined:
    Apr 23, 2014
    Messages:
    13
    Likes Received:
    0
    Re: How to fix a vibrating / shaking / crazy P2V+ camera gim

    I'll let the image speak for itself. :) [​IMG]
    The cover over the black ribbon cable is missing since I was taking the gimbal apart to see if your fix would work for me.
     
  20. dezunka

    Joined:
    May 27, 2014
    Messages:
    51
    Likes Received:
    0
    Re: How to fix a vibrating / shaking / crazy P2V+ camera gim

    My camera is like that too. We aren't talking about that motor. There are three. Two have the silver caps (the one you are looking at and the one that goes through the base plate that attaches to the Phantom). The third motor doesn't have a silver cap. It's the motor directly behind the camera. This is the one that appears to have the failure issues.

    There should be no "play" in this motor where the magnets are located. If you can gently pull this motor apart where the magnets are located then your motor has the problem. It should not come apart.
     

    Attached Files: