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DJI Phantom V1.1.1 Loss of control

Discussion in 'Phantom 2 Vision + Help' started by SBGfilms, May 3, 2014.

  1. SBGfilms

    Joined:
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    Location:
    Cowes, Isle of Wight, UK
    So yesterday I had a small crash, nothing major from about 4 feet up, managed to break a prop but all seemed OK.

    Today I head out for a fly and my Phantom started acting really strange.
    I did a compass calibration and got the green light. As I took off I noticed the Phantom really struggling to hover in the same place, it would start accelerating backwards on its own and drift around.... not good

    So, I landed and did another calibration and took off. Everything was now OK'ish, still a slight movement whilst hovering. So this is where I made a big mistake..

    I was flying pretty high, getting some shots and all seemed OK until I started to bank a turn, the Phantom would pitch on it's side and then start accelerating towards the floor! In my panic I switch to ATTI mode then back to GPS mode and it seems to stabilize again for just a moment.

    As I descend the Phantom really looses control and banks right on its side and accelerates towards the floor, I tried to save it but it was too late. I hit the floor pretty hard. Bent my landing frame, fully broke my Feiyu Tech Gimbal

    Here's the video of the final disastrous moments;

    http://youtu.be/_M9ktGZMI_E

    I've been flying this thing long enough now to know that this wasn't pilot error, there was something else going on here. It seemed like every time I'd pitch or roll the Phantom wouldn't return itself upright again.

    My mistake was that I shouldn't of flown it if I wasn't 100% that the thing was flying properly.

    All my gains are left as Default and everything is updated to the latest firmware.

    Anyway, any ideas whats caused this? Could it be the stock controller? Or something wrong with the compass?

    Any help would be great as it's already destroyed £140 gimbal.
    My cheap FPV kit seems indestructible though!
     
  2. 4wd

    4wd

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    I'd guess the small crash has damaged the GPS sensor, it's only a thin ceramic-like thing,which can crack without falling to pieces completely.
    You'll probably want to open it up and have a good look around anyway.
     
  3. OI Photography

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    Definitely check the GPS receiver as 4wd suggested, and you'll want to connect to the Assistant software and check the IMU and compass values reported in the "Tools" section. Might want to go ahead and do a full IMU calibration as well while you're in there...that's usually a good idea after any hard impact.
     
  4. J Dot

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    Location:
    Sarasota, FL. USA!
    Hello,
    It is always good to hook phantom to PC ASSISTANT, after any crash or hard landing, and recalibrate IMU ( inertial measurement device ) this device takes readings from ( gyroscope ( spinning motion ), accelerometer ( forward-back-side/side, and up-down movements ) and finally compass ( where it is ( latitude, longitude, altitude ). Any of these 4 components, can be scrambled in a hard landing or crash!

    First hook topic assistant
    Look for ( TOOLS ) tab ( 4th tab over ) on top
    Check your MOD VALUES ( modulus: another word for absolute value )
    ( Mod is a average taken from ( x,y,z axis )

    Gyroscope should be : ( 0.0-1.5 ) if not RECALIBRATE IMU
    Accelerometer should be : ( .98-1.02) if not RECALIBRATE IMU
    Compass should be : ( 700-2400 ) if not RECALIBRATE IMU AND COMPASS

    Jerry D
    USA
    ( J Dot )
     
  5. SBGfilms

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    Location:
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    Thanks for the help! I'm away without the copter at the moment but will try your suggestions when I get home in a few weeks.

    Thanks again!
     
  6. SBGfilms

    Joined:
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    Location:
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    So advanced cali and some waving a magnet around my compass to get decent values seemed to have fixed the stability in GPS mode.

    Thanks for your help!