Feb 16, 2020: added above video.  Comment: Density of wings, deliberate line crossings.
Topic
Kite Trains and Stacks
with an eye to serve good practical works
Jan. 22, 2020, post by Dave Santos

Here is a hasty note set that covers some thinking about kite trains in the technical kite community and its AWE understanding:
  • Open AWE has long studied how to tap lattice waves, not seeing them as undesirable "instability."  Kiters simply damp train oscillations with tails and other details, when the application is public display.

  • Dynamic Stability as a "resonant" mode has been considered ideal for tapping for energy.

  • Tapping free energy is done in crosswind plane. Longitudinal axis holds the zero-point energy.

  • Typical kite trains passively develop upward traveling waves.

  • These traveling waves can reflect by strong turbulence transients, gradient, or pilot lift.

  • Traveling waves vary according to wind velocity, but the mode is stable across a wide range.

  • Traveling waves generally entrain to the moving wind field.

  • Canonical normal modes are distinct phases. These have potential application to modulate sweep area (i.e., 1st mode sweeps most).

  • Standing wave modes develop by special design and/or conditions. Kite Arches naturally support standing waves.

  • We have been inspired by lattice wave energy in crystals as a heuristic similarity class, avoiding high-dimensional intractability in our models.

  • Does two line steering input, with canceling pull-turn push-turn constant train-segment length, ease computation issues?

  • Wubbo's SpiderMill concept, as a kite network of tri-tether nodes, has been Open-AWE's to extend and develop. TUDelft has completely neglected it.
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This sort of rough kiter's domain art could go on indefinitely, but this gives one a conceptual snapshot. Hoping others' future work can further validate empirical kite network research in AWE, dating back to 2007.
Jan. 26, 2020, post by Joe Faust
Hyperkites: some miscellaneous quotes:

  • "Hyperkites were invented by Randy Tom of the Bay Area Sundowners, and now exclusively licensed through Kites Unlimited in Atlantic Beach, NC." 
  • "Along with Randy Tom, Frederick Belloff, aka Rick Bell and John Caiazza were all responsible for the invention of the Hyperkite.I worked for Rick and was engaged to his step-son in the early 90's. I still have the original Hyperkites manual that they composed yet never published"
  • "It does seem that "Randy Tom", the designer of the original Hyperkites has long been out of business."
  • "Hyperkites (The company) closed its doors in 1998 after the dominance of the "Big Wing" took over the stunt kite community."
  • "This is a five-pack of Hyperkites, bought in the early 1980's. Made of ripstop nylon with wood spars, these were sport kites made to fly in stacks or trains. Sold in kite stores across the United States, they were popular because of their "show" potential when flown in very long stacks (30 kites +). Hyperkites have been the kite of choice for the Bay Area Sundowners, the oldest continual-performing sport kite team in the United States. Custom Hyperkites, with dynamic graphic sails were a specialty of kite artist Randy Tom. I remember them being sold in 3- and 6- packs, but this is a 5-pack, so that may be the way they were sold."

Dec. 24, 2019,   post by  Dave Santos
Best Kite-Train Lattice-Wave Video
Jim Nicholls' 685th kite review elegantly captures kite-train lattice-wave essentials-

50 Kite Train - but not for long!



Dec. 5, 2019,        post by Joe Faust


Sept. 20, 2019       Dave Santos
Kite Trains/Stacks gain Traction in AWEcademia

Note that too-close a kite stack self interferes. so looser train-spacing is the best power-to-weight-and-airspace. The hidden issue is whether active digital Optimal Control of many-body problem is not better done by embodied passive dynamic stability methods. Formal AWE theory is catching up to classic multi-kite train and stack practice long reviewed and endorsed here. Sad that Wubbo's SpiderMill is not cited as an antecedent, still, great to see the Ivory Tower again coming around to widely known informal kite art. This is a key paper to move rigorous AWE topology theory toward laterally extended kite networks interconnected aloft. Congratulations to the authors, two well known to us (Reinhart and Moritz) and two new (Johem and Thilo)-

(PDF) Optimal control of stacked multi-kite systems for utility-scale airborne wind energy   Jochem De Schutter, Thilo Bronnenmeyer, Reinhart Paelinck, Moritz Diehl, Rachel Leuthold 
 
Practical Note: Too-close a kite-stack self interferes, so looser train-spacing is best power-to-weight-and-airspace. The undiscussed issue is whether active digital Optimal Control of the hairy many-body problem is not better done by embodied passive dynamic stability methods.
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