Welcome to PhantomPilots.com

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

Phantom is not stable after IMU calibration.

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

  1. Cytranic

    Joined:
    Dec 24, 2014
    Messages:
    17
    Likes Received:
    0
    So my phantom + was perfectly fine. For whatever reason I clicked the IMU advanced calibration and now its unstable in GPS.

    I use to be able to sit and spin the phantom with the rudder stick and it would sit and turn in one spot, even fighting wind.....

    Now it seems there is a huge delay, when I spin the rudder, the phantom flys off 4-5 feet from its position and then tries to fly back to the gps...If I sit there and spin the rudder, it will do toilet bowl moves and spin around..

    I've tried calibrating it over on a level surface, I"ve tried the compass calibration..

    This thing was a dream to fly, now its uncontrollable. It even seems to wiggle in the air like its hunting a compass setting..

    Did I screw up permanently? I made sure there were no metal structures or interference when calibrating.
     
  2. Mako79

    Joined:
    May 16, 2014
    Messages:
    3,416
    Likes Received:
    568
    Location:
    Sydney Australia
    Sounds more like compass issues. Make sure you are on the latest firmware as this fixes magnetic declination.

    And the faster means it will less likely stay in one spot.

    Are you doing compass calibrations as per manual?
    Find open field. Remove phone keys metallic items.
    I raise the phantom above my head and spin 360 and then point the nose down a spin 360 again.
     
  3. Cytranic

    Joined:
    Dec 24, 2014
    Messages:
    17
    Likes Received:
    0
    yup on latest firmware on everything...Its also a version 3
     
  4. Shuether

    Joined:
    Dec 27, 2014
    Messages:
    109
    Likes Received:
    0
    Location:
    Middle Alberta, Canada
    Now that I think about it, I'm seeing the same thing on my V3. It was fine, would hold a spot and yaw full circle without moving. Ran the IMU advanced calibration, now when I yaw it move than 10 degrees it seems to wander off a few feet before tying to find its way back. Also fully up to date on firmware. Its been too cold the last couple days so I haven't flown in bit. Will try a compass calibration when I do.
     
  5. Cytranic

    Joined:
    Dec 24, 2014
    Messages:
    17
    Likes Received:
    0
    Yup, sounds like my situation.

    I'm hoping someone can help me solve this... I use to be able to spin this thing in 10mph winds and it would just sit and hold its position. Now I spin, and I'm having to do major corrections....

    Someone on youtube had his main controller detach inside, but I just pulled this thing apart and nothing is loose. I've never crashed at all. I cant imagine a "calibration" would throw this thing so far out of wack.. Its almost like the compass is out of wack, and no amount of calibration will help..


    Is there a way to factory reset this thing?
     
  6. Cytranic

    Joined:
    Dec 24, 2014
    Messages:
    17
    Likes Received:
    0
    I just spent 30 min trying to configure this thing... Seems worse every time I do the calibration.... This thing is unflyable now......I should have never screwed with the factory settings.... I'm starting to thing everyones flyaway's are a result of IMU calibration...


    Any ideas? I have 12 GPS's and doing a yaw will make it go 15 feet off course....
     
  7. rotorwash

    Joined:
    Dec 27, 2014
    Messages:
    118
    Likes Received:
    8
    I have a gimbal issue from a non crashed V 3. copter so I have calibrated mine more than a dozen times in the advance settings. I have had no issue with flight after. Make sure the copter is properly connected to at least 6 satellites before flight. Sometimes it takes longer.
    Also did you calibrate the your transmitter in the RC software?

    Finally here is a tool to tell you how many satellites will be in the sky every hour. I was surprised to learn that some hours of the day I might only have 4-5 satellites for an hour.
    http://satpredictor.navcomtech.com
     
  8. Cytranic

    Joined:
    Dec 24, 2014
    Messages:
    17
    Likes Received:
    0
    Its definitely not a satilite issue....it seems to be a balance issue from the IMU calibration.....


    I had 11 SATs just the last hour.....the bird will hold its position on the dot with GPS.....course lock produces good results too so that rules out the compass...its only when I yaw does it fly off course....it always seemed to drift to my right....I recalibrated with a table mat under one side and the problem seemed to shift to the back and left.....

    I'm placing it on my perfect level marble floor.....could the leveling be the issue?
     
  9. rwskinner

    Joined:
    Dec 5, 2014
    Messages:
    68
    Likes Received:
    0
    Location:
    South Texas

    I've experienced the same thing. I've got mine where it flies again and is fairly stable but it's not like it was before the calibration process.

    Richard
     
  10. Mako79

    Joined:
    May 16, 2014
    Messages:
    3,416
    Likes Received:
    568
    Location:
    Sydney Australia
    I think you are letting the phantom idle too long when you have it plugged into the pc.

    Make sure the adv imu calibrations are done without the temp warning and it should 5ake 3 minutes or less.

    Charge the battery and wait 30 min. Find a levelled place. Make sure its levelled with the horizon. Use a bubble spirit level. Start tge phantom assist and have the imu calibration screen ready. Plug phantom in while its off. The moment you turn on the phantom, calibrate the phantom immediately. Wait for green ticks. It should be very quick. If its taking a long time to get green ticks then the imu sensors will be less accurate due to the phantom getting warmer.
     
  11. 4wd

    4wd

    Joined:
    Mar 31, 2014
    Messages:
    2,532
    Likes Received:
    421
    Location:
    North York Moors
    Also don't walk around anywhere near it as even slight movement of floorboards is possibly enough to cause a problem.
     
  12. Shuether

    Joined:
    Dec 27, 2014
    Messages:
    109
    Likes Received:
    0
    Location:
    Middle Alberta, Canada
    I redid the IMU advanced calibration last night. I left it on the floor this time. It did seem better when flying today. I didn't watch super close because it was -18°C and I was loosing light fast at sunset but it didn't see to wander as far when yawing.
     
  13. Pmcdn

    Joined:
    Jan 26, 2014
    Messages:
    227
    Likes Received:
    0
    Location:
    Houston, TX
  14. Shuether

    Joined:
    Dec 27, 2014
    Messages:
    109
    Likes Received:
    0
    Location:
    Middle Alberta, Canada
  15. Cytranic

    Joined:
    Dec 24, 2014
    Messages:
    17
    Likes Received:
    0
    HI, I'm Cory from that thread on DJI's forums. It will take alot of IMU calibrations and business cards to get it right, but this technique will correct the yaw drift.
     
  16. crash1sttime

    Joined:
    Oct 31, 2014
    Messages:
    926
    Likes Received:
    74
    Location:
    Manchester UK
    So is this just for the Vision plus unit ?

    I have no issues with drift during yaw on my standard Vision.
     
  17. Cytranic

    Joined:
    Dec 24, 2014
    Messages:
    17
    Likes Received:
    0
    Seems to be a vision plus issue. The IMU is real sensitive to being level.
     
  18. crash1sttime

    Joined:
    Oct 31, 2014
    Messages:
    926
    Likes Received:
    74
    Location:
    Manchester UK
    And another reason why i'm glad I chose the standard Vision unit.
     
  19. Shuether

    Joined:
    Dec 27, 2014
    Messages:
    109
    Likes Received:
    0
    Location:
    Middle Alberta, Canada
    Good to know. Looks like I have my next few days of flights planned out, thanks Cory!
     
  20. ELHEAPO

    Joined:
    Nov 17, 2014
    Messages:
    669
    Likes Received:
    213
    Location:
    Blighty
    Do you do the calibration in basic calibration or advanced?