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How Accurate Is Litchi Waypoints

Discussion in 'Pro/Adv Discussion' started by Flipsonic, Jul 16, 2016.

  1. Flipsonic

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    Just installed Litchi and planning a mission for the first time. Has anyone tested how accurate the bird flies to each waypoint? I would imagine that it's not that accurate, maybe a few feet off. If so, how much off is it by?


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  2. Richard Gozinya

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    Why don't you measure it and tell us ?
     
  3. alokbhargava

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    Accuracy of positioning depends on two factors: 1. How accurately you work out the coordinates of your waypoints and next 2. how accurately your drone follows them using its GPS. Litchi doesn't play any role :)

    I have been able to get 3-10' accuracies.
     
  4. Flipsonic

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    Thank you sir!


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  5. flyNfrank

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    I just watch a friends video using litchi waypoints and the mission had 75 waypoints that went pretty good. He owns a number of dji aircraft and uses 2 P3 Standards at the same time both using the same mission. Actually the 2nd aircraft's mission is a little higher in altitude so that it looks downward on the lead aircraft which is usually some 30ft to 50ft out in front.

    He says the coordinates are based on google's longitude and latitude entries. You can see each aircraft has variances from the other. Their distances from objects are not a carbon copy from one another.
     
  6. Richard Gozinya

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    I'm having a hard time with step 1 NOT being a given.
     
  7. MikeON

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    I think many people on these forums have unrealistic expectations of the accuracy of consumer-grade GPS. Using auto-land, my P3A will sometimes come down within a foot of takeoff point, but other times it might be off 25 or more feet. I usually take over control before touch-down. I've been using hand-held GPS for many years and noticed the same variations. The same considerations would apply to waypoints in Litchi.
    Surveyors can achieve much greater precision using sophisticated equipment with multiple receivers.
    Trimble - GPS Tutorial - Surveyors Do It Differently
     
  8. Mark The Droner

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    You might find this thread interesting: "Follow the Leader"

    The OP flies two birds at once on the same Litchi mission - through the city of Baltimore - especially the Inner Harbor - except the second mission is adjusted to be 25' away from and behind the first mission at all waypoints. You're watching from the second bird. He starts off launching at the same time with the birds 25' apart. But at the end of the mission, he says the birds appear to be about 100' apart (see posts #9 and #22).

    See his video here (and I strongly suggest you max the screen):

    Tangent: Note the bright yellow flashing of the tail lights indicating loss of the control signal.
     
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  9. Meta4

    Meta4 Moderator
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    Consumer GPS is going to put your Phantom within 1-2.5 metres most of the time but occasionally it will be further out.