Crash cage or dome

Discussion in 'Cinestar 8' started by Mikko Kosonen, Jul 12, 2012.

  1. William Johnston

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  2. Andy Johnson-Laird

    Andy Johnson-Laird Administrator
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    I was thinking of writing a Java program to do some additional break out of the data. Is there any chance that I might be able to get a copy of your source code and build upon that, please? Happy to sign a non-disclosure agreement and send you back the code I produce.

    Thanks
    Andy.
     
  3. Andy Johnson-Laird

    Andy Johnson-Laird Administrator
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    By the way, here's the output from the second flight with a Maxamps 11000 battery, no camera on the gimbal but a windy day. Seems disappointingly short. Need to do some more testing:

    Flight Time 2012-10-01T22:55:46Z
    Flight Duration 7 minutes 58 seconds
    Average Current (Amps)
    3.8 6.3 4.8 8.0 6.3 8.2 5.5 5.8 0.0 0.0 0.0 0.0 Total=48.6
    Maximum Temperature (Celsius)
    50.0 58.0 59.0 79.0 74.0 81.0 67.0 61.0 0.0 0.0 0.0 0.0
     
  4. William Johnston

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    Heh, I was afraid someone might ask for the code. It's a quick hack job and so not that impressive structurally, but sure you can have it. I zipped up the NetBeans project:

    ftp://cast-ftp1.cast.uark.edu/wgj/AnalyzeGPX.zip

    Things I was thinking of adding were minimum temperatures, the standard deviation of the currents, and nice text output for all the error codes.
     
  5. William Johnston

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    Nice. If a lot of people posted this, we would have some sort of baseline to go off of.

    Did that flight take your whole battery?
     
  6. Andy Johnson-Laird

    Andy Johnson-Laird Administrator
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    Thanks!

    I'm not having any joy in getting the ftp site to prompt me for a log in or respond. Firewall?
    Any chance you could email it to me at ajohnsonlaird AT me.com please? Sorry to be a pest.

    Not entirely. I did one shorter flight before that. I flew until 14.4v. I need to analyze the previous flight -- I'll do that now.

    Andy.
     
  7. William Johnston

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    Oh I messed up the address. It's here:
    ftp://cast-ftp1.cast.uark.edu/wgj/AnalyzeGPX.zip

    I'll edit the above post to fix it.
     
  8. William Johnston

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    This page https://www.quadrocopter.com/Cinestar-8-RTF_p_627.html says the the Cinestar 8 is supposed to fly for about 25 minutes with a GoPro camera on 6200mAh 4s battery.

    That's what I was hoping I would get someday. Does anybody get that kind of time?
     
  9. Andy Johnson-Laird

    Andy Johnson-Laird Administrator
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    Hmm. For reasons unknown, I got an empty .GPX for the preceding flight. I would have expect a much longer flight with an 11000 mAH battery, especially given those current draws. It's very windy here today, so I'll have to wait until tomorrow to recharge the battery and re-test.

    Andy.
     
  10. Andy Johnson-Laird

    Andy Johnson-Laird Administrator
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  11. SteveWilson

    SteveWilson Member

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    I've never tried it with a GoPro, but 25 minutes on a single 6200 seems...optimistic, to put it politely.
     
  12. Andy Johnson-Laird

    Andy Johnson-Laird Administrator
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    With a QC6200, temp 74F, field elevation about 350 ft AMSL, 3-axis gimbal but no camera, and in 5mph, gusting 8mph wind, with the C8 on hover:

    Flight Time 2012-10-01T22:43:35Z
    Flight Duration 8 minutes 25 seconds
    Average Current (Amps)
    4.1 5.8 4.3 7.0 5.5 7.5 5.5 6.1 0.0 0.0 0.0 0.0 Total=45.7
    Maximum Temperature (Celsius)
    53.0 55.0 56.0 68.0 68.0 79.0 67.0 64.0 0.0 0.0 0.0 0.0


    Andy.
     
  13. William Johnston

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    To be fair, is does say "Max Flight Time" so we are talking about just hovering and perfectly windless conditions.
     
  14. William Johnston

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    Your #4 and #6 motors always pull more current.

    Another useful modification to the program would be to average the numbers accross multiple flights.
     
  15. William Johnston

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  16. Andy Johnson-Laird

    Andy Johnson-Laird Administrator
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    Significantly, the "dry weight" of TabbyTabb's C8 with battery was 6.8 lbs.
    The C8 RTF I have, with the 3-Axis gimbal (but no camera) is 10.94 lbs with a QC6200 and a QC1200 (gimbal lipo) included. (The QC6200 accounts for 1.28 lbs.)

    I'm having a hard time accounting for 4.14 lbs difference.
    And also I note that at 10 lbs AUW, the current draw was 78 Amps (whereas the average on mine is 45.7 Amps as you see above).

    Maybe TabbyTabb could confirm what the configuration was:
    1. Were the Radians on board?
    2. HDMI Converter on board?
    3. What was the electronic board configuration? NC/GPS/Extension PCB?
    4. What flight battery?
    5. What gimbal battery?
    6. Was the current measured peak or average and how was it measured?

    It seems like we're getting a lot of conflicting data here doesn't it? I hate the Universe when it does that....

    Thanks
    Andy
     
  17. Howard Dapp

    Howard Dapp Active Member

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    Andy, actually that's 78A at almost 17LBS. That was a 10LBS payload on an octo weighing 6.8LBS.
     
  18. Andy Johnson-Laird

    Andy Johnson-Laird Administrator
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    Ohhhhh.... I was thinking it was all up weight but you're right, Howard....Duh. It's turning into a long week....

    Still puzzled by the C8 with battery is only 6.8lbs, though when I'm starting at 10.94 lbs.

    Andy.
     
  19. William Johnston

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    His unloaded Cinestar probably doesn't have the gimbal.
     
  20. Andy Johnson-Laird

    Andy Johnson-Laird Administrator
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    That would certainly account for it, William.

    I think I might try some experiments along the same lines, but loading up the gimbal with different weights so that I can get some real-world data. Or just use different cameras from a CX760 to a Hassie H5D. No. No. What am I thinking....flying an H5D....I don't think so..... ;)

    Andy.
     

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