https://groups.yahoo.com/neo/groups/AirborneWindEnergy/conversations/messages/25759
This monocopter seems to have a suitable configuration for an AWES.
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This is one of the historic roots of AWE rotors. Practical conversion to wind power has some interesting complications. The motor position is not where wind acts unless attached to a tensioned pilot-lifter line. The original design was not good at translational flight, and its hard to set this up with the rotor plane crosswind. Gravity causes the asymmetric rotating mass to pump the line. It then becomes a KiteLab/kPower looping-foil.
Seems a bit difficult to control. But it is not actually very different to a looping rigid wing, except center of rotation is inside the wing.
kPower looping foils (rigid and soft) are passively controlled. Active control is hard; best relegated to supervisory passive-stability exception-handling, like basic failure-sensing and kite-killer function.
No control, only using a lifting kite?
The propeller goes up the apparent wind. If we prefer down apparent wind position, putting the propeller in the opposite side then working on balancing.
Reminds me of Shepard’s original Australian prototype leading to SkyWindPower well over a decade ago, maybe two. Shepard used a single blade opposing a small counterweight. Back then I was just beginning to notice the symptoms characteristic of “The professor Crackpot Syndrome”… It amazed me how inventors would just come up with stuff that, to me, made no sense. The symptom I saw was what I call "ruining a perfectly good invention by adding other inventions that are unnecessary and spoil the performance, seemingly “just to be different”. I was trying to figure out why someone would use a counterweight instead of another blade for a propeller. Especilly for an airborne application, since a) the weight contributes no lift, and b) it is located tight to the hub so must be heavier than the blade. “Why?” I wondered. Does Shepard have a method to his madness, or is he just kind of nuts, hooked on “new” nd “unexpected” features. The only reasons I could think of were raising the Reynolds number and increasing RPM for the generator, but I remained unconvinced. My thought was that I could not think of a single successful single-blade-with-counterweight flying device or propeller of any kind, airplane, helicopter, nothing. So why would Shepard want to RUIN a perfectly-good invention by adding a crackpot unproven (probably inadvisable) feature? Or was he just such genius, so far ahead of the curve, that this all made sense and I just could not see it? I had an open mind. I decided either this guy Shepard was really ahead of the curve, with extremely advanced knowledge, or he was introducing me to a major symptom of “The Professor Crackpot Syndrome”. The years rolling by have sorted it all out for me. “The syndrome” remains alive and well. But I wondered back then, what does this inventor know that I don’t? I was like “Uh-oh, I’d better get going with my airborne wind energy ideas, because others are starting to figure it out.” I figured Skywindpower or whatever they were called back then would have something flying and making power in a year or so. It seemed like and emergency to get my stuff flying before Shepard took over the flying wind energy space. That was way back when I was naive like all the newbies today, believing every press-release, thinking the coverage represented people who really knew what they were doing. Silly me, I thought when a magazine said someone would have a product on the market next year, it was really true. I had never noticed that the press-releases almost universally turned out NOT to be true. Heck I was still using the space elevator people as a role-model back then. It was years before I figured out that "Space Elevator was just hype for now, better suited for the moon at some distant future date than Earth anytime soon. So I had little doubt that the Shepard single-blade-with-counterweight flying windmill was going to make a big splash. Of course today, so many years later, even with the crackpot-counterweight gone, the Shepard effort seems to have stalled, or at least changed to something much more low-key, back-burner at best, possibly mostly just abandoned. The early renderings got people excited, but I don’t remember seeing too much from them lately. This particular version looks like fun, especially if you have to run to avoid being hit by that .049 engine, but I think what it really shows is there are almost unlimited configurations of wings and weights and engines that could potentially remain airborne. A good example is the RC “flying lawnmower” often seen at little airshows and demos. So many years into it, AWE is still looking like “land of the lost”. Funny I got a call from Dr. Peter Harrop’s organization the other day, inviting me to attend some event. I told the lady they should take a tally of all the predictions of Dr. Harrop over the years, and see how many have come true. I told her I did not think he had any particular special insights or knowledge above what everyone else was aware of, and that I did not see that his pronouncements had any specific veracity. I seem to remember his multi-thousnd-dollar AWE report predicting a 100 kW product on the market this year, for example. Wow, thanks Dr. Harrop. Ever heard of “The Professor Crackpot Syndrome”? Maybe you should charge $3000 to teach people about that! Imagine being in a land where, if lost, you could ask anyone for directions, but never get a valid answer. That is the land of AWE, land of the perpetually-lost. Sounds like a repeating bad dream when you have a fever. Yet this “dream” is real…
Shepard never did a monocopter AWES as far as the public record seems to show. He was an executive, not a prototype engineer. Niether did the actual pioneer of AWES autogyros, Brian Roberts, ever do a monocopter version, as far I know.
Can Doug please cite a real source behind his reasoning? As for-
Doug "My thought was that I could not think of a single successful single-blade-with-counterweight flying device or propeller of any kind, airplane, helicopter, nothing.
There is obviously the the Maple Seed every aeronautical expert thinks of, that’s worked for millions of years-
There is also lots of tradition in advanced aeromodelling, which continues-
https://www.bigbruceracing.com/product-page/2016-f5d-single-blade-reverse-rotation-props
kPower solved “monocopter” reaction-mass for looping foils by replacing the mass with a tether, and it works well.
In fairness to friends, PJ and David Shepard, whom I hold in good esteem, Doug’s ST driveshaft is more mass-challenged by excess “weight (that) contributes no lift” compared to dubious Sky Windpower monocopter case implied.
Here a turbine with a propeller is used as counterweight, so it makes sense.
I’d modify that statement of “makes sense” to “could possibly be rationalized, but remains unproven and unverified”. In general, either it’s a better way to do wind energy, or it’s not.
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