Super bumpy in the wind: OK?

Discussion in 'Cinestar 8' started by Steve Maller, Jan 21, 2013.

  1. Steve Maller

    Steve Maller UAV Grief Counselor

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    I am concerned because my CS8 is really very unstable in strong winds (10-15mph+). Here is a short flight this morning. My settings are pretty generic (see enclosed pic), Radians on my 2-axis gimbal are set to 50% gain (i've used up to 120%, and the results are no different), camera is a Sony CX760V, and I've also enclosed the GPX file. Below is a video of the flight (where you can clearly see the wind) including the captured FPV video from the little security camera on board.

    The Radians did a pretty remarkable job, considering. The bird is much more stable (very smooth, really) in calm air. But it's not always calm around here.

    So my question is this: should I expect better stability in such a strong wind?
    Or should I just fly somewhere calmer? :)
    Thanks, y'all!
    Steve
    Parallels Desktop-snap001.jpg

     

    Attached Files:

  2. Josh Lambeth

    Josh Lambeth Well-Known Member

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    Try 100, 120, 21 for P, I, D, and gyro stability to 5-6 and see how it does. I had my old MK setup in winds around 20mph+ and it was still stable considering:

    - it was about 10mph wind when I took off. Then watch the trees. You will see a big bump in the footage about half way through... that is when the dust storm hit me. Then you will see how much of the booms are in the shot just trying to keep the copter in one place.

    Josh
     
  3. Pavlos Antoniou

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    The video is 0.01 :( :(
     
  4. Steve Maller

    Steve Maller UAV Grief Counselor

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    My video? It seems to work for me...does it not work for you guys?
     
  5. Josh Lambeth

    Josh Lambeth Well-Known Member

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    Worked fine for me.
     
  6. Steve Maller

    Steve Maller UAV Grief Counselor

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    Yikes. Do you guys change your FC gyro settings depending on wind strength?
     
  7. Gary Haynes

    Gary Haynes Administrator
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    Steve some folks do work out multiple settings so that they have something for high wind. And wasn't the Maverick surf championship held out there this weekend. Monster surge, 20+ foot waves, lots of wind. Surprised that your CS is still in the same county...
     
  8. Josh Lambeth

    Josh Lambeth Well-Known Member

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    I have heard some do... I do not however.

    Josh
     
  9. Steve Maller

    Steve Maller UAV Grief Counselor

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    Gary, I can see Mavericks from my bedroom window...we're exactly 4 miles as the crow flies. But not my copter. Between the real copters, the wind, the salt spray and the lack of a stable landing surface, I was quite happy to watch the webcast stream on my computer. :)
     
  10. Steve Maller

    Steve Maller UAV Grief Counselor

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    I just tried that and it was a bit less twitchy.
    I guess I'm getting bolder about flying the Cinestar when there's a wind out there. Used to be with my quad I didn't take it out of the car if there was anything more than a soft breeze.
     
  11. Josh Lambeth

    Josh Lambeth Well-Known Member

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    Try changing the ACC comp a bit as well. Somewhere in the 60-70 range. I am at 97 on mine but thats with the upgrade. I don't remember what it was before but I think it was somewhere around there.

    Josh
     
  12. kjetil tønnesen

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    hello josh
    calling from norway:))
    my cs8 is flying very well
    if i change the acc ,what will i do to the machine,will it be smoother?
    i have never change the acc before
     
  13. Brad Meier

    Brad Meier Active Member
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  14. Steve Maller

    Steve Maller UAV Grief Counselor

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  15. Andy Johnson-Laird

    Andy Johnson-Laird Administrator
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    Steve: Looks like you're right in the curl-over (the air roiling over the house and/or trees).
    The real problem is the copter is at the mercy of the airmass and curl-over can change direction and velocity so quickly, I suspect there's a good chance that it can exceed the control authority of the copter -- so you'll see turbulence that just shakes the bird like crazy.

    I've flown sailplanes in windy conditions and the curl-over near to the ground around trees and houses can be ferocious. You can go from +ve wind speed to -ve wind speed in a few milliseconds (so +20 mph to -20 mph).

    Andy.
     
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  16. Steve Maller

    Steve Maller UAV Grief Counselor

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    That's very helpful, Andy. I flew today in calmer winds in a different location, and it was super smooth and everything feels better now.
     
  17. Benjamin Rowland

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    I've found that in windy conditions, it's even more important to have props that allow you to hover around 50% throttle. So if you're currently hovering around 30% throttle, then you would want to go to props that are smaller or have less pitch. Or as an alternative, you could add another battery to add a little more weight (my typical solution). This forces your props to spin faster and the copter seems less likely to overcorrect in gusty wind.

    Please note that I'm flying with a Hoverfly flight controller and I'm no aerospace engineer. These are just my observations.
     
  18. Dan Coplan

    Dan Coplan Member

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    Do any of you use a wind meter (anemometer?) to determine whether or not conditions are ok to fly in or do you just gauge it by what you see and feel around you? Any sort of rule of thumb, like up to 10mph ok but not more (as an example)? I guess it's impossible to tell how windy it is above you without a reference like a flag or trees.
     
  19. Andy Johnson-Laird

    Andy Johnson-Laird Administrator
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    You can generally get a good idea of wind speed by how it hits your body, but I use a wind meter mainly to convince the camera op that it's too windy... ;)

    But, as you say, there is the wind speed and the amount of gusting. Ten knots steady and you can handle it without too much problem, 10 knots gusting 20 and it's really hard to fly steadily.

    Then you have to factor curl-over into the equation -- close to the ground the airflow is much more turbulent as the air wraps around and over trees, buildings etc. If it's really bad you can get situations where the winds aloft will be say, 10 knots from the North, but as you come down to the ground the wind can be 10 knots from the South. Not a good day to go flying! (In full sized sailplanes we used to land "hot" by adding half the windspeed to the normal approach speed, but I had instances where that almost wasn't enough....)

    Andy.
     
  20. Jei Swan

    Jei Swan Member

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    wel its nice to know. other are looking at this. cause i have no i dea what to change to get a smoother video after stabilization.
    i havent changed anything on the radians still running factory settings at the moment i have (red black blue) on the vibration dampeners red being closest to the centre with canon 5dmk2 and the 24m tilt shift lens. and no matter what i try i still get jumps in the video. granted the weather here has been bad. no wind below 10/15 mph and always raining.

    If im rambling ori make little sense im getting a headache trying to figure out all the little things i need to do to get my CS8 to produce smooth video.
     

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