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Ground Control - Two Turns

Discussion in 'Phantom 2 Vision + Discussion' started by tcope, Feb 14, 2015.

  1. tcope

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    I've only used Ground Control twice now but each time the UAV reaches a waypoint and turns, it will turn back to the orginal heading and then turn again the new direction. It's sort of a double take turn. Anyone know why it might be doing this? Here is an example. Jump to 2:10m (linked) and you can see it easily. It does the double take every time, it's just that if the turn is small its more difficult to see. Thanks

    http://youtu.be/b_7KH1xn_Nc?t=2m15s]
     
  2. eseckinger

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    Mine does the same thing most every time. Sometimes it will not though
     
  3. JDNC

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    I've posted about this also. Mine will do this sometimes too and some have said it appears to be that it does it most when turns are 90 degrees or more. My bird is on its way to Burlbark's for some mods so I haven't had a chance to test this. I will say that every time my bird did this the turns were greater than 90 degrees, more like 120 or so! Something to look into anyway. Hope this might help.
     
  4. tcope

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    I went out again yesterday and dis a few runs. It does seem that you are correct, it only does the double take when the turn is greater than 90 degrees. Really screws up nice video runs.
     
  5. MapMaker53

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    Gave me a moment of panic when I saw a similar turn in the wrong direction. But then the quad paused, turned back in the correct direction, and proceeded to the next way point. And, yes, the angle of turn in my case was also greater than 90 degrees. Next time I'll add a couple of extra way points to make a similar turn so the quad doesn't get confused.
     
  6. tcope

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    Well, I sent a messager to DJI about this so I suspect it should be corrected at any moment.

    I'm guessing that it's a programming error that has to do with the UAV knowing which way to rotate in order to make the turn (clockwise or counter clockwise).
     
  7. JDNC

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    I guess it will take a few more flights to know for sure, but it sure looks as if this might be true. I wonder what's causing it. I just hope that this is a constant as we can at least deal with it until it's hopefully corrected.
     
  8. Sketch6995

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    glad to see its not just my bird......mine does it 2 or 3 times then heads in the correct direction.
    you wont see it in any of my vids......I edit that out of course lol.
    I think its using compass calibration like dance to figure out the next waypoint, or perhaps just to verify.
     
  9. tcope

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    So here is the official word from DJI on this matter:

    Thank you for contacting DJI, I apologize for the late response. If the firmware is up to date with the latest 3.8 Assistant Software, you can perform an Advanced IMU calibration located under the Tools tab. You can check to see if you are under the correct Mod ranges for gyro, compass etc. You would find that information by hovering over the question mark above the mod ranges.

    Underneath the compass readout, you have the option to perform a Basic or Advanced IMU calibration, it is recommended to perform an Advanced calibration when you initially start flying in order to obtain satellites more efficiently and allows a more stable flight. This should address the double take issue that you are experiencing.

    If you continue to have issues, please feel free to reply to this email or call our support center for further assistance. You may contact us Monday-Friday, 9:00am-5:00pm PST at 818-235-0789.

    DJI Customer Service North America



    I did the calibration but have not flown yet. If someone else would test this and post their results it would be much appreciated.
     
  10. eseckinger

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    This is definitely not the cause. I have done advanced calibration 3 times since I got mine and its never been bumped or crashed.
     
  11. JDNC

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    I have to agree. My bird's IMU Mod's have been in their correct ranges. Matter of fact dead nuts on, but I admit I've never preformed an advance calibration as I didn't see any reason to. But of course I reserve my right to be wrong! :)
     
  12. tcope

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    Yup.... tested and it did not change a thing. My specs were within normal but I did the advanced calibration anyway. Took it out today for a test... same thing. Will send another email to DJI. I still think it's a programming error in the Ground Station app. The drone would need to be programmed to turn the lesser rotation in order to make the correct turn (which ever way is less then 180 degrees). It makes this calculation correct but then it seems like the programing had it manually turn back as if to confirm.

    [youtube]https://www.youtube.com/watch?v=ZKhQIIPQwvk[/youtube]
     
  13. ccase39

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    Yea calibration has nothing to do with it. Mine does the same. I think it only happens when you do a greater than 90 degree turn. I will have to pay more attention. Its just like DJI to give some generic answer that has nothing at all to do with what you are asking. I have a strong suspicion a lot of their reply emails are auto responses that respond based on key words.

    I have been waiting 2 weeks to find out if they received my Phantom that I sent. Tracking said it got there 2 weeks ago. Emailed a week ago and nothing. When I have 9 hours to waste I will call.

    Thank god for recources like this board!
     
  14. tcope

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    So here is DJI's follow up response:

    The issues that you're describing require for you to send in your unit for repair.

    In order to be issued an RMA (Return Merchandise Authorization) number, we encourage you to call our support staff via phone to discuss your options


    Needless to say, I'm not buying this either (I guess every Phantom they have sold needs this "repair" then). It's gone from a calibration issue to that of a need for "repair". From what I see, if I send it to them I'll be without it for at least a month. Than I suspect that they will simply return it (as I think it's an issue with the app anyway). So I wrote back to them and asked then to explain what needed to be repaired. I see this email conversation going no where fast. I don't expect that I'll ever get a good/correct answer from them but I have nothing to lose by trying to get a straight answer.

    Just wondering... does anyone _not_ have this issue?

    On a side note (teaser)... I may have a lead on 1st party coverage for drones (would exclude fly-aways and theft).
     
  15. flyNfrank

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    It's good to see you don't take them for granted. Especially the service department. They told so many lies to me I will never send them anything of mine again. If it didn't have to do with warranty I would not have sent it to begin with.

    Mine vPlus started doing the dosie-doh after the 1st update when we 1st were given the GS. When watching the compass data on my Flight Logger, it shows it jumping all over the place. This most likely has something to do with this issue in the GS as well?

    Btw, has anyone ever noticed the IMU reading differences between cold and hot? (you can't do advanced IMU calibration when hot, but you can see the current readout after doing advanced calibration and then let it sit there until after it heats up)