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First crash (more of a flop) - "Gimbal Obstructed"

Discussion in 'Phantom 2 Vision + Discussion' started by RhythMick, Jan 23, 2015.

  1. RhythMick

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    Hi all,

    I think I rushed my pre-flight checklist trying to catch the last of the daylight. **** - lesson learned. I have it on my list to check that the props are ALL THE WAY DOWN but I must have missed that one. Looked ok on idle, but on take off one flew off the the bird tipped over from it's take off perch (case, on bench) into the snow on the ground.

    Two of the props were obstructed. It didn't respond to CSC but I was able to get to the battery button fairly quickly and turn it off.

    After a lot of checking I powered back on. The gimbal appeared to be ok but the Vision app reported something like "Gimbal Obstruction" and I could see the gimbal constantly trying to adjust itself. Quickly powered off and came home.

    I've watched THIS https://www.youtube.com/watch?v=5iTz3Dd2Ecs and https://www.youtube.com/watch?v=Y3Ii1i3-x3I. They seem to be about the camera not levelling though. Before I go digging in there I'd like to get advice on how best to proceed.

    The ribbon cables look ok, no obvious sign of damage.
     
  2. RhythMick

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    OK a little more.

    The gimbal seems to have free movement on all 3 axes.

    I've removed the back to check that the camera is level and all is fine.

    I'm going to recalibrate the IMU and see if that helps. Just not happy that the gimbal is trying to do something when power is on.
     
  3. RhythMick

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    I've recalibrated the RC, the compass, the sticks in the Phantom Assistant and finally done an Advanced IMU calibration. During this I made sure I included calibration of X1, both on the RC and on the Phantom.

    It clearly helped. I have control over the gimbal in the Vision app. I can bring the camera up and level and am no longer getting the "Gimbal Motor Obstructed" error in the Vision app.

    Not quite perfect yet though. The camera is nice and level and I have full control, but with the camera between 45 degrees (ish) and level the motor is quietly straining. Not all the time, on and off. I'l post a link to You Tube in case anyone can give me any clues. I'm reluctant to have the motor straining for long, but will repeat the calibrations and see if it improves further.
     
  4. RhythMick

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    This you tube video

    https://www.youtube.com/watch?v=pMl3jH_PNNc

    refers to a gimbal making a "buzzing" sound and the guy received advice from DJI as follows...

    Place the Phantom on a table/desk, power up just the Phantom and connect up the USB port on the Phantom to your computer. During this calibration process, it is important not to move the phantom or bump the table/desk.

    Open DJI Phantom 2 Assistant.
    Click on Tools
    Reset BTU Info first
    After a little while on the Basic tab, Check IMU Status and Basic Cali will be available
    Do Basic Calibration next
    Once that is done click on the Advanced tab
    Do Advanced Calibration next. This will take quite a few minutes.
    Once that is done, power cycle the Phantom and all should be good.

    I'll follow that. Can someone educate me on what the BTU info is ?
     
  5. TuT

    TuT

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    A bit of water from the snow will freak the gimbal out. See how it behaves after it dries out.
     
  6. RhythMick

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    OK still getting the "buzzing/straining sound with the camera above 45 deg.
     
  7. RhythMick

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    OK thanks. I'll leave it alone and go fret over a beer.
     
  8. RhythMick

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  9. burlbark

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    It doesnt take much to cause one of the motor shafts to bind. I have repaired around a hundred now. I have to remove the shafts and anneal them because they are tempered. If you try to straighten a motor shaft without removing it from the housing you will break the shaft and the potentiometer on the control board, then you pay me another $100 to fix it..... ;)

    Be very careful attempting any repair yourself, the majority of bricked gimbals I see are caused by owners breaking the hinging ribbon cable connector off the gimbal main board or camera body. Then you might as well buy a new one.

    Jeremy James
     
  10. RhythMick

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    Thanks - very aware of how delicate they are. I wouldn't try to do much to them.

    As a repairer, what's your view on the various gimbal protection attachments doing the rounds ? Any use ? I appreciate you may have a vested interest ...

    If it doesn't sort itself out I'm thinking the best way would be to remove it from the P2V+ and continue flying while it's being repaired. Any reason not to do that ?
     
  11. burlbark

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    The only protector I would recommend is the bottom landing gear plate. Everything else is not going to help in a crash. I am sure many will disagree, feel free to clamp stuff all over your Vision ;)

    The ribbon cable breaking used to be a big deal because they where not available. Thats all these add ons try to stop. By locking the 2 halves together at the roll axis is puts all the stress on the pitch axis to separate. That motor shaft is $50 by itself and the potentiometer/brushless control board is guaranteed to break now and the ribbon cable may still need replacing. And the roll axis will still need to be fixed.

    Learn to hand catch and fly the quad and this will almost never be an issue.
     
  12. RhythMick

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    Thanks yes one of the first things I did was get used to hand catching. Today's flop (caused by a dumb newbie error, not checking the props were tight) has just reminded me how easy it is to go wrong.
     
  13. benshaniphotos

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    Can I pay you to fix mine for 100??? :D Im having the same issue. The gimbal is vibrating when I rotate the craft either direction.
     
  14. RhythMick

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    Sadly the gimbal is still straining this morning. Last night I gently ran a warm (not hot) hairdryer over it for a few minutes and left it to rest.

    To recap, without power the gimbal appears to have free movement on all 3 axes. With power on I can tilt the camera through it's full range but it's straining to move the camera when it's above 45deg.

    Looking for advice as to next move.

    Since the gimbal is straining I'm assuming it will just wear the motors out to fly it. If I tilt the camera down to 45 so it's not straining is it still likely to wear it out ?

    I'll go chat to the dealer I bought it from, see what they say.

    If the gimbal needs to go for repair, is it possible to fly the P2V+ without it ? I think I read somewhere that without the gimbal you can't get wifi/telemetry ?
     
  15. RhythMick

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    https://www.youtube.com/watch?v=qOIXS99Fhlw

    Short video of the gimbal strain noise.

    I'm gonna go ahead and remove the gimbal and camera, fly line-of-sight for a while. Have emailed dealer and will take it in for an opinion next week (with gimbal reattached)
     
  16. RhythMick

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    Thoroughly enjoyed flying the P2V+ today without the gimbal. No Telemetry or WIFI, so flying by line of sight. Wish I'd done that as soon as I got it.

    Will focus on flying skills for a while. The P2V+ is ridiculously easy to fly, but skills around that matter (like not rushing the checklist) and getting used to reacting right whichever way it's facing.
     
  17. burlbark

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    You more than likely bent your pitch motor shaft. Its $150 repair. Please dont try to do it yourself unless you are willing to wreck a couple gimbals figuring it all out.
     
  18. RhythMick

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    Thanks. Are you UK based ? I'll see what the dealer says, but for now I'm flying without it.
     
  19. zryall3

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    So while practicing in manual mode, I crashed and the only damage, beyond a couple broken props, seems to be that the camera gimbal has bent slightly off of center as the arm comes down from the plate it all hangs from. It does not bind and functions properly except my "level" view on the iPhone is gone and it's tilted the amount of the bend damage. Knowing the ribbon is very fragile, does anyone have recommendations or experience with bending this arm very careful back without damaging any of the axis rods or the cable itself? I was considering using a small wrench or a pair of small vise grips to hold the arm away from the cable, and bend it. I just don't know if putting the opposite leverage on the arm that bent it in the first place is a good idea. Amazingly after flying it for 2 batteries today to make sure there were no other issues, the view leveled itself right at the end of the flight. Does the Phantom have some way of knowing the camera is not level and it compensates for it? I'm hesitant to send the Phantom in for the 4-6 week turn time and since everything else works fine. I don't think the base plate carbon fiber $40 piece I see advertised would have kept the impact from bending the arm, but if someone has proof otherwise, I'll certainly spring for one of those. Thanks all.
     
  20. burlbark

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    There does appear to be an accelerometer in the camera itself and does compensate for some degree of error.