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IMU in the dji inspire "flight controller" or the GPS antenna?

Discussion in 'General Discussion' started by Felixdkat, May 17, 2016.

  1. Felixdkat

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    anyone know where the IMU is located?

    Is the IMU in the dji inspire "flight controller" or the GPS antenna?

    prolly the flight controller.... just wishful thinking since i can't get it to cal.
     
  2. The Editor

    The Editor Moderator
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    Yes it's internal to the FC.
    Why will!it not calibrate? What's it doing?
     
  3. Felixdkat

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    tried cooling in the fridge, got up to 23%..... but that was the best it did... gives the out of temp range "shut off for 5 minutes" message .... can't seem to get any further no matter what i do.... perfectly level. mod is .95 so it isn't that far off.... using an iPad so there is only "advanced calibration". i understand that the earlier software for windows tablet allowed for a "basic" cal. might try to find a friend with an android device and see what happens... just frustrated at the moment...
     
  4. pwackinspire

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    The IMU is located in the front of the body but you need to take the nose cone and top shell off to get to it , if your getting temp warnings then i would check the Fan that is located on the top of the IMU/Lightbridge/FC unit .There is a small cable coming out of the left side of the lightbridge (see pic) , you can see the cable from the side of the Inspire , i would check that it hasnt been damaged.
    dji-inspire-1-lightbridg.jpg installation-inspire-1-remove-front-canopy-1024x683.jpeg
     
  5. Felixdkat

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    pwackinspire- thanks.... i had it all off and checked the fan blades. Some threads said that an out of balance fan would keep it from calibrating. Blades looked good. I will take another look at the wire.

    How does the fan unclip? I didn't want to force anything but i wanted to unclip it and see how long to heat up. I might just replace it and see if it makes any difference.


    Following suggestions from other threads:

    I tried multiple times, all failed.
    Paired a different remote, still failed.
    Cooled down in fridge, removed and failed. Tried inside fridge, still failed.
    Inspected fan- looks ok, but will try a replacement just to see.
    Inertia tested on all axis and watched as the values changed on each axis to verify the IMU was not Physically stuck in one or more axis. Simply rolling on each axis changes the values, a push away without release (like a chest pass in basketball) would give higher values. Each axis yielded similar values.
    (From "The Editor")
    Gyroscope (undisturbed) should be 0.00
    Accelerometer -0.99 - 1.01

    Compass (once calibrated separately as an IMU calibration does not have anything to do with compass) 1400-1600 (Ideally as close to 1500 as possible)



    My IMU Values:

    IMG_0068.PNG IMG_0072.PNG

    Today I am going to try and format an sd card on my inspire, and reinstall the firmware update. If i understand correctly 1.08 won't rollback?
     
  6. pwackinspire

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    I think its held on with the 3 screws that are visible from the top of the fan, but if you can power the inspire with the imu in place im pretty sure the fan should come on and run all the time.

    You would probably be best doing the power up test first to see if its running before you take it off.

    Good luck!!!!!
     
  7. The Editor

    The Editor Moderator
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    Hmmmm....strange one. Of course it is actually possible you have a faulty IMU/Flight Controller but what are your actual mod values? I know you quoted another thread of mine where I gave the ideal ranges but curious to know what yours are (at rest) currently.
     
  8. Felixdkat

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    IMG_0068.PNG


    how do you "rollback" a firmware upgrade on the inspire? the remote has an option under the hat, but the bird stays at 1.08
     
  9. The Editor

    The Editor Moderator
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    Just load up 1.7.0.90 on a freshly formatted MicroSD card and fire up the Inspire (remote must be off).
    The downgrade should begin. However, you will have to downgrade your remote as you mention (little hat icon) so they match.