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Poor GPS positioning on the RC

Discussion in 'Inspire 1 Discussion' started by Aviator, Aug 30, 2015.

  1. Aviator

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    To demonstrate what I am talking about please download this KML file and open it in Google Earth.
    The Red line is the flight of the AC which is perfect.
    The Magenta line of the RC should be the same location as the take off and landing position of the AC.
    You will see that the Magenta line is no where near the proper location of the RC

    The KML file can be downloaded at http://www.weymouth-angling.co.uk/test.kml
     
  2. Aviator

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    I must also point out that the RC did not move its position at all between take off and landing..
     
  3. Kilrah

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    Nothing new?
     
  4. Aviator

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    Thanks for that input, most useful addition to the discussion.
     
  5. Scotflieger

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    @Aviator There are 2 issues here:

    1. The log file saved to the DJI Cloud and accessed via Cutter's webware, records the RC position at a lower rate (5-10Hz) than the aircraft and at a lower accuracy. This is logical as the RC is unlikely to move a great distance.

    2. The I1 RC GPS is very poor in the quality of GPS data received or its visibility of GPS satellites. Using a iPad Air 2 without SIM, I recently realised that I had no built-in receiver. I have since brought a bluetooth Dual XGPS160 SkyPro GPS receiver which has greatly improved my RC/iPad GPS accuracy but does not overcome point 1 above.

    This Google Earth screen grab shows the standard RC GPS position in magenta. It shows me walking from my rear garden take off area to my front garden to observe the flight.

    RCOnly.jpg

    This one was taken from today's flight using the GPS bluetooth receiver. I cannot see any real improvement in the position logging.

    RCPlusGPS.jpg
     
  6. Aviator

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    screenshot.jpg @Scotflieger The KML file I posted was when I was also using the bluetooth Dual XGPS160 SkyPro GPS.
    I can confirm the same findings as you that it has made no difference to the RC reported position..
    The RC position should be at the same point as the takeoff and landing points as can be seen in this screengrab!
     
    #6 Aviator, Aug 30, 2015
    Last edited: Aug 30, 2015
  7. Aviator

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    I have just use a chart plotter to work out difference between the maximum distance and the actual position of the RC and the max error in position is 180 meters!
     
  8. Scotflieger

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    I have not seen that magnitude of error. 10m is my worst..
     
    #8 Scotflieger, Aug 30, 2015
    Last edited: Aug 30, 2015
  9. Aviator

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    The least error was still 35 meters!