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    S
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    Best posts made by somalley

    • RE: Poor GPS Fix

      Building upon what @ROBERT-JUDD did in his testing, we made a shield out of a tinfoil solder cup to isolate the GPS antenna from the rest of the drone. This resulted in an almost immediate track of 10+ satellites. The EMI problem is real. We are now working on designing a 3D printable cone similar to what the cup is doing that we plan to paint with an EMI coating that will be our more rugged long term solution.

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      ModalAi should be providing clear disclaimers about this problem before people go and spend thousands on this drone!

      posted in PX4 Autonomy Developer Kit
      S
      somalley
    • RE: Poor GPS Fix

      @ROBERT-JUDD @Alex-Kushleyev

      We built upon the shield/cone concept since it showed promise and worked to eliminate any tiny gaps and cracks where EMI could potentially leak through. We designed and 3D printed a cone that would come together on both sides of the GPS antenna mount with enough spacing for them to slide around the posts. The inside of the cone and some of the post had copper tape applied to it. Aim of this is to shield the GPS antenna from all RF below the cone and only receive RF from above. As you can see from the screen captures, the results are very promising. I think my team and I can now move forward in testing that was previously blocked by the poor GPS performance. Hope this helps and inspires some other fixes.

      You may want to consider a small RF shield cone on top of your mast.

      Here are the results from our custom shield and testing.

      b7882c75-c941-4022-9e39-81d67600eb9e-image.png
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      2bc59b8a-3f2d-4dee-a765-5547e174f611-image.png

      posted in PX4 Autonomy Developer Kit
      S
      somalley