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  1. 30secs

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    So my new p4 is acting a little word l weird. I had oa on and flew by power lines if that matters. Compass cal was made before at a safe place.

    When I flew by me, the p4 would often move around horizontally, and at times kick the motors and move a few feet... Not sure why.

    Any thoughts? Is it the oa/sonar/power lines, or is it something with the quad?

    It also drops in altitude which I is really annoying actually.. And tilted gimbal when panning.
     
  2. eaglegoaltender

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    Cant say for certain this may be your issue but I had very similar issues including the P4 hovering on an obvious angle.

    I did a "cold" IMU calibration and so far so good as to previous issues including a faster "aircraft warm up time".

    Never a good idea to fly near power lines - residential hydro feed lines aren't an issue as to control of the P4 - however I noticed odd movements once when flying within 100ft of high voltage lines. The ROA (right of way) for high voltage lines is around 100 - 150ft around them - inside that area there is definitely magnetic forces that can affect your signal. Even grass with morning dew can be seen "twitching" from the EMF within the ROA.
     
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  3. jwt873

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  4. 30secs

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  5. AsiaFlyer

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    Looks like it went into ATTI a few times, this would explain horizontal movement
    Altitude problems is a common fault with the P4, a factory reset in DJI Assistant and fresh IMU and sensor calibration helped a bit
    Also a side note, you should never take off on a partially discharged battery
     
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  6. Sim597

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    Agree with you except maybe on the "cold" IMU calibration, I say maybe because it's possible you do like me, and calibrate in AC a soon as bird is able to start calibration (meaning everything is on and ready to start right away, before it even initializes)
    Cold from say the fridge to working temp is just too hard and demanding on these critical parts, and certainly one of the hardest things on and to do to IC boards, of any type, unless specific and made for these temp swings, at super fast times.
    I've found the AC on with batteries and unit at 69-70* has been for me really good calibrations. To test I have also done them after a landing, and even though the difference is arguable and minute, it does seem to be the "cold" ones seem to last longer.
    This all started in Inspire threads and issues those owners had, when DJI then stated online then in their manual that a cool environment is to be used to calibrate IMU


    Sent from my iPhone using PhantomPilots mobile app
     
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  7. eaglegoaltender

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    Agree 100% - when I mentioned "cold", for certain, I meant in an a/c environment, not from refrigeration (probably should have said "cool not cold" as to environment)!

    Leaving the "bird" in a fridge then bringing out to room temps, adding the battery and turning it on to calibrate is just asking for trouble (condensation etc.).

    I have done both an outdoor IMU calibration and an inside a/c cooled room calibration. I find the "aircraft warming up" time to be fairly significant comparing both environmental conditions.

    Thanks for pointing that out - (cold). Safe filming n flying....Sim.
     
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