smart osd altitude settings wrong flying 20m says 6m?

Discussion in 'Electronics' started by Jason Smoker, Aug 19, 2015.

  1. Jason Smoker

    Jason Smoker Active Member

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    Took my x8 for a spin yesterday using fpv and noticed that my alitutude reading is totally wrong from the microkopter. I was first flying LOS about 20m then switched to fpv and noticed that altitude reading said 6m when it should of been 20 or so?
    Is there something i can adjust here? is this from the smart-osd or the microkopter?
    please help
     
  2. Andy Johnson-Laird

    Andy Johnson-Laird Administrator
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    Jason: Did you by chance get a GPX file for the flight? If you did, that would be a good reference point for the altitude data that was on the data bus between the MK cards and also the data fed into the OSD card. The OSD card just monitors the data packets between exchanged between the various MK boards and converts the relevant data into displayable form.

    As far as I know, there is no "adjustment" that can be done to either the MK system or the OSD to correct for this.

    Andy.
     
  3. Jason Smoker

    Jason Smoker Active Member

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    ok here is the file from the last flight
     

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  4. Andy Johnson-Laird

    Andy Johnson-Laird Administrator
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    Can you identify where in the flight where the reading in the GPX file is wrong? I'm afraid I can't look at the GPX file and know that...

    Andy.
     
  5. Jason Smoker

    Jason Smoker Active Member

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    Andy I talking about all the time just says it to low when i know just by looking at the heli its much higher:confused:
     
  6. Andy Johnson-Laird

    Andy Johnson-Laird Administrator
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    The GPX file altitude values look fairly normal. It starts at zero, but indicates 1.45 meters when the aircraft landed.
    Did the copter takeoff and land in pretty much exactly the same place?

    If the answer is yes, the takeoff and landing points were essentially the same, then it's pointing to a problem with the pressure transducer on the flight control board. You might want to visually inspect the solder joints for that transducer and make sure they're good (you could even re-flow the solder as precaution). Otherwise you may need to replace the Flight Controller.

    Andy.
     
  7. Jason Smoker

    Jason Smoker Active Member

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    ok thanks Andy the fc is almost brand new so hmm!! I am not going to replace it seeing it works fine expect for readout of the altitude

    is yours pretty close to what it should be?
     
  8. Andy Johnson-Laird

    Andy Johnson-Laird Administrator
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    Yeah. Pretty good. There is usually some variation because atmospheric pressure is a pretty fickle creature and can change a bit during a flight. The other problem is that the air turbulence around the copter can create bogus compression/rarefaction -- but that's what the gust filter on the pressure transducer is designed to counteract.

    Andy.
     

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