Flying M5 in strong winds

Discussion in 'MōVI M5' started by Thai Christen, Apr 7, 2015.

  1. Thai Christen

    Thai Christen Member

    Joined:
    Dec 22, 2014
    Messages:
    50
    Likes Received:
    4
    Hi All,

    Until now I have only flown in low wind and got decent footage with my M5 on a X8 Setup (Camera is GH4 Speedbooster with Duclos Cinemod Leica-R 19, 24, 35, and Tiffen VD ND filter).
    So today I tested my setup how it handles strong wind. Wind was constant at approx. 20-25Km/h (12.5-15.5 mph) with guts up to 50km/h (31mph). While my X8 takes the wind guts without any problems I have a stability issue with my M5. Footage is bumpy (movement in y-axis) at constant wind and super shaky (movement in all axis) with guts.
    So my question is what is the max wind speed that the M5 can handle safetely? Do you need to adjust any parameters in the software to improve stability? I pump up the gains a little bit but it didn't help. Only oscilation will kick at times (flying at higher speed or wind guts). Anything else one can do? Change rubber dampening?
    I would be glad to get some feedback.

    Furthermore, can anyone of you confirm this:
    - I get the smoothest footage if I fly with the wind (even in very strong wind)
    - worst if flying against the wind (forward or backwards)
    - usable footage (post stabilized required) when flying with nose 90 degree to wind direction

    Thanks a lot!

    Thai Christen
     
  2. Steve Maller

    Steve Maller UAV Grief Counselor

    Joined:
    Oct 30, 2012
    Messages:
    3,979
    Likes Received:
    807
    Can you post a photo of how your gimbal is configured with the camera on board?
    Aerodynamics are important on a MōVI, too.
    But the copter may be overcorrecting in the wind to the point that it's actually hard for the MōVI to keep up. I generally don't go for super high stability in the wind...I just fly it more attentively :eek: . Does that make sense?
     
  3. Thai Christen

    Thai Christen Member

    Joined:
    Dec 22, 2014
    Messages:
    50
    Likes Received:
    4
    I am sorry but I don't understand what you mean by overriding overcorrecting. And how is flying attentively?
    The only thing I want is decent footage that can be stabilized in post. Also I would like to know where the limits are so I can accommodate. I heard some operators give a 20-25km/h range as the max wind speed. No matter what setup they have.

    Sure I will upload some pics tomorrow morning.

    UPDATE: some links on my setup
    http://www.blog.thaichristen.com/?p=1641
    http://www.blog.thaichristen.com/?p=1688
     
  4. Thai Christen

    Thai Christen Member

    Joined:
    Dec 22, 2014
    Messages:
    50
    Likes Received:
    4
    No one out there who flies with the Mövi in strong wind and can give some feedback about stability?
     
  5. Chris Fox

    Chris Fox Active Member

    Joined:
    Apr 14, 2013
    Messages:
    463
    Likes Received:
    86
    G'Day Thai,
    It is all in the balance of the gimbal and the vibration isolators, 20-25km winds are not that strong, I would be expecting good results in those conditions.

    Are your vibration isolators working effectivly
     
  6. Thai Christen

    Thai Christen Member

    Joined:
    Dec 22, 2014
    Messages:
    50
    Likes Received:
    4
    Hi Chris,

    Thanks for your feedback! If 20-25km is not strong how much can you push it and still get usable footage? What setup are you using?

    At 20-25 I get usable footage (not smooth though but fixable in post) but it really depends in which direction I fly. Flying against wind makes footage not usable at all. And wind guts at 50km definitely overwhelms my setup.
    Assuming that if I get smooth footage at low wind my Mövi is well balance, or I am wrong?

    I am not sure how effectively my isolators work because I have not tried any other system. I use the adaptor plate from kopterworx
    http://kopterworx.com/shop/camera-gimbals-remote/movi/movi-m5-adapter-for-dji-s1000-frame.html

    It is basically for DJI S1000 but I can mount it on my Carboncore Cortex by using the same DJI attachment (as shown in the picture).
     
  7. Steve Maller

    Steve Maller UAV Grief Counselor

    Joined:
    Oct 30, 2012
    Messages:
    3,979
    Likes Received:
    807
    I know a lot of folks fly with retracts, but those legs on yours are huge, and I would be willing to bet that when the copter's flying in strong winds those legs will be flopping around quite a bit. They aren't attached to the gimbal, of course, but the movement that they could be creating could translate to the frame and could cause problems. That's the reason that Freefly designed the MōVI with the legs on the gimbal itself. I think that's a more stable system.

    I would mount a Mobius or GoPro to the frame itself somewhere to record a flight and see if there's a lot of movement in the frame and/or the gimbal. I've done that a few times and have sometimes been surprised at what I've seen.
     
    Dave King likes this.
  8. Thai Christen

    Thai Christen Member

    Joined:
    Dec 22, 2014
    Messages:
    50
    Likes Received:
    4
    Hey Steve,

    Sorry but the image with the retracts is misleading. I took that photo shortly before I landed (was operating myself only, so no one nearby). I fly with retracts up only (second image)
    http://www.blog.thaichristen.com/?p=1765
    I don't think that the retracts will cause much more vibrations. Retracts work similar to DJI s900/1000 or Hammer from Kopterworx.

    So if I understand it correctly, what you are saying is that the M5 can easily handle very strong wind. The vibration is mainly caused by the frame or poor isolation.
    What is your setup and what was the max. wind speed you have ever flown with usable footage?
     
  9. Andy Johnson-Laird

    Andy Johnson-Laird Administrator
    Staff Member

    Joined:
    Jul 31, 2012
    Messages:
    10,376
    Likes Received:
    1,162
    Do you have a lens hood on the camera, Thai? The image you posted doesn't show one, but that lens has a pretty large "wind sail" area.

    I've found that a lens hood can produce a lot of vibrations depending on the wind direction. Have you tried with a smaller lens just to see if that might be a factor?

    Andy.
     
  10. Thai Christen

    Thai Christen Member

    Joined:
    Dec 22, 2014
    Messages:
    50
    Likes Received:
    4
    Hi Andy,

    What you see is the Tiffen variable ND filter with standard 77mm thread. I never use lens hood. All my Leica lenses are modified to take 77mm. In fact I see a lot of folks using similar lens size (Zeiss) flying their RED Epic with Mövi (mostly M10 and few M5). So I really don't know if it is only me or do other folks don't fly when it is too windy. Which I doubt because mostly you will rather find windy situation than calm.

    The reason why I bought the M5 is because I felt limited using DJI Z15 Gimbal which only allow you certain Cam-Lens Combo. With the GH4 Speedbooster and my beloved Leica-Rs I get very creamy and cinematic images that can easily match RED MX footage. In addition they flare beautifully when not using lens hood.

    Thai
     
  11. Andy Johnson-Laird

    Andy Johnson-Laird Administrator
    Staff Member

    Joined:
    Jul 31, 2012
    Messages:
    10,376
    Likes Received:
    1,162
    Hi Thai:
    Well, there goes another of my ill-fated theories! :)

    Andy.
     
  12. Steve Maller

    Steve Maller UAV Grief Counselor

    Joined:
    Oct 30, 2012
    Messages:
    3,979
    Likes Received:
    807
    Thai,
    The physics of those long, somewhat flimsy retract legs look to me like they could cause quite a bit of skaking.
    I've flown my Cinestar-based 500mm X8 frame at 24-25lbs with a GH4 in 20mph winds and had it work OK. Certainly not as nailed down as calm air, but certainly usable. I'm using an unmodified M5 with Freefly's MR package (legs included), a Toad In The Hole, and the stock Cinestar vibration isolators with a mix of blue and black silicone bands.
     
  13. Thai Christen

    Thai Christen Member

    Joined:
    Dec 22, 2014
    Messages:
    50
    Likes Received:
    4
    Andy: No problem may I ask you what setup you are using and if you have ever encountered stability issue in strong wind?

    Steve: 20mph is a good value. Would you mind sharing a video with the footage shot at this wind speed (without post stabilization)? So I have a reference to look for.That would be kind.
    I will definitely look at the retracts and check with the manufacturer.

    Thai
     
  14. Steve Maller

    Steve Maller UAV Grief Counselor

    Joined:
    Oct 30, 2012
    Messages:
    3,979
    Likes Received:
    807
    Here's a recent shot on a windy day. MōVI was set for single operator (me) and GH4 had a .9X ND filter on the 12mm Olympus lens. All clips up to 1:00 or so are SOOC. A couple of the ones after that point were warp stabilized in Premiere.

     
  15. Thai Christen

    Thai Christen Member

    Joined:
    Dec 22, 2014
    Messages:
    50
    Likes Received:
    4
    Thanks a lot for sharing, Steve. I appreciate it.
    By single operator you mean majestic, right?

    I certainly see wind in your video, but at 20mph I would have expected it to be much stronger. The indication are the white flags. They would be much more straight and fluttering faster, I guess. Also there are not much movement in the grass and bush. Or maybe I am mistaken because I am watching from my iPad Air Retina (full screen).
    I can definitely say that the wind condition I was testing was much stronger. Maybe I can upload a video to show you.

    Here is a video of what I get with my setup in mild wind condition. Footage are not stabilized nor cropped. Piloted and operated by myself in majestic mode.
    http://www.blog.thaichristen.com/?p=1690
     
  16. Chris Fox

    Chris Fox Active Member

    Joined:
    Apr 14, 2013
    Messages:
    463
    Likes Received:
    86
    Thai, I would be expecting to get great footage through until about 35km/h ... beyond that it is usable but after about 50km/h of wind speed on the gimbal (your speed plus headwind) you are pushing the friendship.

    This is shot in a variety of conditions, the wind turbine shots the recorded winds on the tops of the turbines was around 45-50 ...

     
  17. Thai Christen

    Thai Christen Member

    Joined:
    Dec 22, 2014
    Messages:
    50
    Likes Received:
    4
    Chris,

    The turbine shot looks amazingly smooth for 40-50km/h! (well, still watching on my iPad but I can tell). Did you apply any post stabilization?
    I am wondering which setup you used for that shot.

    Thai
     
  18. Chris Fox

    Chris Fox Active Member

    Joined:
    Apr 14, 2013
    Messages:
    463
    Likes Received:
    86
    M5 and Red Epic, on one of our old copters that has been retired now. A little bit of warp to iron out one or two bumps, just what you kind of expect in that environment. All the footage looks great on a big screen.
     
  19. Thai Christen

    Thai Christen Member

    Joined:
    Dec 22, 2014
    Messages:
    50
    Likes Received:
    4
    Your reel definitely looks fantastic, Chris. :)
    Side note: did you modify your M5 (with extension tube?) and is the process complicated?

    Here is the video I shot on that windy day. Look at the grass, the tree and fir to judge how strong the wind was. As I said flying with the wind is best, against the wind worst. About half of the video wind guts messed my M5 and it was not leveled until I descend in altitude. That is strange.

     
  20. Andrew Griffiths

    Joined:
    Jul 7, 2013
    Messages:
    61
    Likes Received:
    9
    In addition to the headwind it's possible the strong downwash is impacting on the camera. The vector of the downwash changes as you fly into a headwind and could be contributing to you problems. Another possibility is the onset of a resonant frequency at certain throttle power levels.

    But I'm just speculating. As has already stated, your best bet is to throw a gopro on the frame to find out exactly what's going on.
     

Share This Page