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IMU takes 5 min. to initialize

Discussion in 'Pro/Adv Discussion' started by iflyhelis, Aug 31, 2016.

  1. iflyhelis

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    It started off with trying to calibrate the compass & I got through that. I then flew away with only a 1 minute wait for all systems to say "Safe To Fly GPS"

    The next thing I experienced was a 5 minute wait, for a IMU Error, & I couldn't calibrate out that error using a Apple 6 I-phone.

    Today, I tried to connect up a Samsung Galaxy Tab 3 (Android) that isn't on the list of approved remote interfaces.

    The best thing about it, is that I was able to do the "IMU" cal & all errors went away!

    Next, is a flight test with the Mini-Tab, I will let you know how it works out for me.

    Kurt
     
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  2. Wheatfield

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    I found cooling the machine down a lot and then calibrating the IMU made for shorter warm up times.
     
  3. Mako79

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    FInd a cool levelled surface in the house. Keep the phantom off for an hour or so if you have flown it.
    Make sure you know off-by-heart where the calibration window is in the GO app.
    The trick is to do the calibration the instant you turn on the phantom. The quicker you get to the IMU screen and calibrate, the quicker and better the calibration and IMU warm times will be.

    Dont throw the P3 in the fridge as this may cause condensation and in some cases false barometric readings.
     
  4. 4wd

    4wd

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    The reason behind this is if IMU is done while warm, the internal barometer has to reach a similar temperature again before you can start in the field.

    I'd say fridge is OK it's no different to putting it outside on a cool evening.
    There's probably no need, although putting it in might need beer to be taken out and drunk in case it gets warm.
     
  5. Numone

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    Did my cold IMU after removing the battery and putting in the fridge. That was 4 months and 40 flights ago without an issue. Now have a few seconds wait before it's ready to fly.
     
  6. iflyhelis

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    Well the Tab 3 video was blocky & after flying 30 feet away it went into (safe to fly no-GPS) I partly contribute this to me running a Hot-Spot to connect my Tab. Because it doesn't have but 25 megs of data a month but my iPhone 6 is unlimited. Problem is the Hot-Spot has a crappy data rate of around 2.2 mbps down & 1.1 up.

    On a down note: On my 13th flight I lost the front left (Black) propeller in flight at about 15 feet up, of course it crashed! The battery popped out part way on impact, I got a few scratches on the motor holder back right (Black) how come the aircraft GPS or stabilization system didn't try to keep it level with the other 3 props?

    Now I need to talk with DJI, BTW the prop didn't break & the plastic threads were intact!

    I think DJI needs to take the colored dome off & drill a hole, & put a locking nut on it to prevent this in flight from ever happening again. Or I will!

    But that is only if my IMU didn't get damaged, I will be testing it tomorrow.

    Kurt
     
  7. MrMcfly

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    Quad copters need all four motors and props to stay in flight, one goes, the bird goes. Hex and octo copters can fly with a motor/prop off. Physics is physics... once one motor is lost, there's no way to counter the opposing props force. Shutting the opposite motor down would just disable one axis of stabilization.

    BTW, it does TRY to stabilize itself. It's just not very good at it (obviously).
     
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  8. iflyhelis

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    Yeah, but if it slowed down a motor on the opposing side of the missing prop, I am sure that a Tri-copter would exist!

    Kurt
     
  9. ElGuapo

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    Do a cold IMU calibration, that solved my problem. I had the same problem until I performed this procedure.

     
    #9 ElGuapo, Sep 6, 2016
    Last edited: Sep 6, 2016
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  10. iflyhelis

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    Fantastic! Thanks for this great information!

    BTW I gave you a like on this subject.

    Kurt
     
  11. ElGuapo

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