Experiments With Electric Line Shuttles

edited March 2011 in General
Brief intro....Back in the early 70's, I experimented with a "parachute powered" line messenger. I had designed it to haul out fishing bait/lures offshore, drop the tackle, and return back down the line. Simple enough, it worked sometimes when the lines didn't tangle. That whole thing got but on the back burner.... Fast forward to fall 2010, While surf fishing,I got reminded about that project again, when I saw some kids at the beach flying this real nice kite. After returning home, I did a quick search on the internet, and ran across Mike LeDuc's Shuttle/AeroKap video's on U-Tube. Mike has produced some of most informative video's that I've found in this area. Combining my original design and powering the drive pulley,(traction wheel) I came up with this prototype model. While "comparing notes" with Mike, he suggested that I check out this KAP site, thinking perhaps some of you folks might be interested in this. Here It is...

This model weighs in at around 10oz. (a little heavy), and travels about 450'/ minute.

Prototype model #.1

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Now that I know this thing works, I'm off on to building a lighter model version #.2

Comments

  • edited March 2011
    Some Video of the drive "traction wheel" and on some "slippery" Spectra #200 line.


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  • edited March 2011
    Looks lighter than what Sir Henry Wellcome was using on his kites 99 years ago!

    image

    If the image does not come through it can be seen here: http://bit.ly/grJZU8 Sir Henry Rig
  • Greatly resembles a prototype we built last year, powerful brushless motor, gear reduced transmission, programmable ESC with powerful holding brake... and it will lift several lbs vertical, rather quickly.

    You're on the right track.

    Troy
  • Mmmmm....OK, perhaps posting this thing here was a mistake. As this being my first real post here,I didn't realize this KAP site was so specific about NOT posting somewhat related content. After reading through the KAP/BAP drama thread, this might fall into that borderline category. If I offended anyone here about deviating from the "purest KAPping" theme, let me know and this will be removed. But really, there is a FF16 up there on the end of that slippery yellow line, and a S95 remotely taking the pictures/video.

    RJoe, Is that 2 lenses on the front end of that camera? Stereo 99 years ago?

    Envision, Any pictures of your "prototype"....ooops, not allowed here? (chuckle)

    Gordon
  • Gordon,
    Welcome to this discussion board! This looks like a perfectly valid thread topic to me. Nice job, I especially like your homemade carbon plate. (Thanks again for the samples ;)

    I look forward to seeing updates of your continuing progress.

    Mike
  • @Gordon,

    Excellent observation! I can't believe I missed that! I will have to do some research into that!
  • My Prototype is for kites, but completely disassemble for integration into the new pendulum design. Never took any photos, but I can tell you it most likely weighs more because of the larger electronics, but it comes in a much smaller package.

    Troy
  • FCB
    edited March 2011
    Gordon -- this forum tends to cover everything remotely related to kites and tethered things and RC aerials and manned aerials, and software, and applications, etc.. Hard to see how your work isn't relevant as it's kites and lines, etc.

    Would be good to link to Mike's thread:

    http://ostro.ced.berkeley.edu/~crisr/discuss/comments.php?DiscussionID=2330
  • A few comments in this thread will be better understood to also review this thread. (for future reference). Hard to interpret whether other forms of AP are not openly discussed here, flickr groups, or both.

    Back on topic, I was going to post a photo of the original frame but couldn't find it, when it turns up I'll add it.
  • "Hard to interpret whether other forms of AP are not openly discussed here"

    Not hard to interpret at all!

    As I just stated: "this forum tends to cover everything remotely related to kites and tethered things and RC aerials and manned aerials, and software, and applications, etc.. Hard to see how your work isn't relevant as it's kites and lines, etc"

    The discussion you linked to refers explicitly to whether you it's bad etiquette to put a BAP photo in the KAP Flickr pool instead of the BAP Flickr pool.

    I'm certain your work with RC aerial gimbals would be tolerated here -- as long as it doesn't dominate the threads. The admin and many others have posted on RC aircraft work.
  • Mike, Thanks for the welcome! I also am interested in your progress regarding the "shuttle" work and creating new lightweight bits & pieces. All of us here can benefit by using lighter components, especially when it is offset by heavier camera's/lens packages (we all love that high quality picture).

    "On the side"....As with my posts on other forums I frequent, I don't color outside of the lines and will not get into the drama threads. There are, of course subjects that need to be dealt with, and need to be discussed (as in the KAP/BAP issue,that seems to have been worked out). This site (so far) is very professional and holds lots (100's of years of experience & wisdom) of good, valuable information for anyone interested in this somewhat complex, mixed hobby.

    Thanks, Gordon
  • Don't worry too much, we are all striving to grab that low level image no matter what is takes!
  • Mike - a quick question which perhaps you have covered elsewhere:

    It appears that when you are testing the shuttles - whether mechanical or electrical - the trip upward always yields a VERY stable KAV test result, as does the trip back down the line. When the zenith is reached and the rig is not moving along the line, the camera loses 95% of that stability. Again, this travel stability appears true with the reel shuttle (which I have - THANKS to your great instructions) and the propeller shuttle as well.

    My question is, why is the image so extremely stable when the rig is traveling upward and downward?

    Thanks.
  • Phil,
    The main reason that I can think of for this is that the aerodynamics of the rig coupled with extra wind resistance as it travels quickly up and down the line tends to dampen out unwanted rig movements and string vibratons. This results in relatively stable videos when it's moving as compared to when the rig is held at a stationary point on the line. Adding a lightweight keel to the pendulum would probably stabilize it even more. Glad to hear you're having fun with the contraptions :).
  • Phil, I was wondering about the "moving" stability the shuttle offers also, (the short 2nd video shows this stability, as does Mikes video of AeroKap fpv). Part of my shuttle design, (borrowed from my original messenger) incorporates a "flag shaped body" to weather vane behind the kite line,for stability. During one of the test runs, I ran the shuttle "backwards" up the line to see if the component weight distribution had any different effect on this, it didn't appear to.

    Mike, I think your a 100% on your observation with the stability phenomenon. The moving shuttle offers a kind of "procession" to dampen the frequencies of the line in the air stream. Thinking about this "stability phenomenon" could be somewhat related to a boat at rest in a choppy body of water (bouncing around) vs. the same boat speeding along over the tops of the waves, smoothing out the boats ride.

    Gordon
  • To add to reasons for stability I think there could be also an effect of constantly changing line lenghts from anchor to rig and from rig to kite and thus constantly changing resonance frequencies of that whole line + rig system. If resonsnce frequencies constantly change particular resonances has little to no time to build up.

    Just note, that even if rig +suspension is more or less a pendulum it's not a pendulum attached at firm, steady point, it's attached to a kite line and it's fundamental frequency is somewhat different than it would be if it hung from fixed point, and is in fact dependant on the placement of it's anchor point on the line.

    rgds
    Sebastian
  • Would there be any gyro affect helping to stabilize from the rotation of any wheels?
  • edited May 2011
    Thanks, Troy. Come to think of it, that surely comes into play....a lot. Hmmmm

    My little wooden shuttle reel (which has at least a couple ounces of mass) is spinning up pretty well when I am reeling it up or down. And Mike's electric is really spinning that prop, even if this version is not directly connected to the trolley.

    The other effects mentioned above no doubt play a role, but you may have hit on the largest contributing element.
  • I'm not sure that the rotating wheels have enough mass to dampen the entire system, but it will surely help.
    Most likely the biggest dampening comes from the fact that mass traveling at any speed want's to go in a straight line. Or saying it differently: mass traveling at speed needs a (large) force to change the direction of speed.

    Think of it as you sitting in a car at 50 mph. If you make a turn you are pushed out. (actually, the car is pushing you in the turn..) It's the same effect.
  • edited May 2011
    As promised, the EPLS-2 (electric powered line shuttle #2).
    Some design advancements:
    1- Improved, integrated line guides,no more fiddling with line capture clips (inspired by frozen fingers)
    2- A lot Faster
    3- A little Lighter
    4-A more compact package
    *It seems that as long as the kite is flying, the is no problem with the line slipping on the pulley (#200 spectra hollow-ace).

    EPLS-2
    EPLS-2
    EPLS-2
    EPLS-2
    The basic frame work...
    EPLS-2
    EPLS-2
    EPLS-2
    EPLS-2
    EPLS-2
  • Impressive design and construction Gordon. The formed 3D molding around the traction pully is particularly cool, looks like a commercially built product. The frame looks like it would be very stiff given it's thickness. What core material did you use for the laminate?
  • Thanks Mike. I have some additional notes at the bottom of each clicked thumbnail picture. The core is 1/8" thick, 3lb density vinyl foam (the blue stuff used in the marine,aircraft,& composite fab industry). The basic framework weighs in @ 2.7oz.

    Phil, do you use your "LeDuc" shuttle on every outing?
  • Flash-FX - No, I have only used it a few times. It is the original reel and works extremely well on my 78" Rok, without any kind of glitch (Thanks MIKE!). More often, I have been experimenting with plain vanilla pendulums to find a great solution for stability. The result will be attached to the shuttle. However, I am intrigued with your electric trolley. Awesome.
  • edited January 2012
    @Wicherd

    Given some particular side move, the faster rig is moving the less direction change is caused by that (side) move. Both things perfectly compensate for each other. That's what Newtonian/Galilean relativity tells us. And that's the reality we experience when walking inside an even very fast train or an airplane. As we can walk and turn in an airplane, rig can swing around it's anchor point.

    Besides all that, there could be third effect: when camera is traveling in some direction our brain is less annoyed by additional swinging. Just as we walk our head moves quite a bit yet we're not bothered by that movement of our "builtin cameras" (eyes).


    rgds
    \Sebastian
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