>From the writings of Rober A. Heinlein to the writings of Marshal
Savage, the idea of people on the Moon, inside large air-filled
volumes (domes, lava tubes, whatever) strapping on wings and flapping
off into the locked-in skies has filled many a space dreamer with
wonder. But will it really work?
1/6 G setting could flap properly-designed wings fast enough and hard
enough to generate lift. I don't have any problem with that. What
bothers me is that every artist's conception I see of this has the
wings at about shoulder level, while the human center of gravity is
between the navel and groin. So the flapping athlete will only be able
to fly about with the body in a vertical orientation. And forget about
going all horizontal and soaring. Nope, this will be more like
treading water, only with big things tied to your arms. Not quite the
graceful, eagle-like image we are used to seeing.
Indeed, with this clumsy fluffling about, it seems that all my cool
ideas for sports based on human ornithopters are right out the
airlock. Sans suit.
Anybody care to give me hope?
On 6/26/07, Xenophile wrote:
(...)
> Now, I don't doubt in the least that a lean, strong person in a 1 bar,
> 1/6 G setting could flap properly-designed wings fast enough and hard
> enough to generate lift. I don't have any problem with that. What
> bothers me is that every artist's conception I see of this has the
> wings at about shoulder level, while the human center of gravity is
> between the navel and groin. So the flapping athlete will only be able
> to fly about with the body in a vertical orientation. And forget about
> going all horizontal and soaring. Nope, this will be more like
> treading water, only with big things tied to your arms. Not quite the
> graceful, eagle-like image we are used to seeing.
(...)
story, the fly suit made the person wearing it resemble more some kind
of aquatic animal (with the big flippers of a whale, maybe) than a
bird/angel. But then that was for zero-g flight in the axis volume of
a rotating space colony, not a partial Moon gravity.
It's a problem that is not so easily analyzed, I think. There are
teams working on real ornithopters now, as well as experts in various
form of "flying suits" used by skydivers. Some of the researchers in
those fields use computational tools, which should be easily tweaked
for 1/6 G to see what happens. Those guys could design a bird suit
that would actually work, even if it means that the wings are actually
attached to the hips or upper thighs, with the arms simply forming the
frontmost edge.
hand-waving (*) analysis.
Best,
- Joe
(*) If you'll pardon the pun.
Joe Strout -- joe@...
Strout Custom Solutions, LLC
From: Xenophile
> bothers me is that every artist's conception I see of this has the
> wings at about shoulder level, while the human center of gravity is
> between the navel and groin. So the flapping athlete will only be able
> to fly about with the body in a vertical orientation.
I think this just means that, unlike the artist's conceptions, in
reality such wings will extend all the way down the sides of the body
and legs to the lower part of the ankles.
I envision these wings not only being attached via shoulder-harness and
hand grips, but additionally via a belt around the middle and straps
around each ankle.
Of course if strapped in this manner into wings which were quite stiff,
this would mean a person could neither bend at the waist nor knees. But
I suspect that such wings would be somewhat flexible, and such flexures
might become part of how one controls one's flight.
Regards,
Mike Combs
> From: Xenophile
> Anybody care to give me hope?
stretch the length of a person's body, allowing the center of lift to be
close enough to the center of mass for controlled flight to be possible.
Theoretically at least.
John
Most nodels of human wings assume using muscular arms to flap or control them. Keep in mind the recent advances in neural connectors. The wings could be plugged into ports that are directly attached to neurons in the brain. With a few weeks of practice, one could learn to flap the wings directly through these neural attachments, leaving the arms free. Also, they could be semi-motorized and battery powered. Perhaps someday, We will learn to power them off the body's own energy system. The technology for the brain to directly control the wings exists in its early infancy today. Paraplegics can control mouse cursors through their thoughts alone, and simple robotics arms and legs are hooked directly into the brains neurons allowing easy control. Perhaps in 20 years or so, the technology will be well understood enough to make brain-controlled body attachments a "no-brainer". (very poor pun, indeed!) Once we can do this, the possibilities for space settlement expand beyond our
wildest imagination.
Douglas May
CWA Local 6215 - Steward
From: "Combs, Mike"
To: spacesettlers@yahoogroups.com
Sent: Tuesday, June 26, 2007 2:25:26 PM
Subject: RE: [spacesettlers] Human Ornithopter Problem?
From: Xenophile
> What
> bothers me is that every artist's conception I see of this has the
> wings at about shoulder level, while the human center of gravity is
> between the navel and groin. So the flapping athlete will only be able
> to fly about with the body in a vertical orientation.
I think this just means that, unlike the artist's conceptions, in
reality such wings will extend all the way down the sides of the body
and legs to the lower part of the ankles.
I envision these wings not only being attached via shoulder-harness and
hand grips, but additionally via a belt around the middle and straps
around each ankle.
Of course if strapped in this manner into wings which were quite stiff,
this would mean a person could neither bend at the waist nor knees. But
I suspect that such wings would be somewhat flexible, and such flexures
might become part of how one controls one's flight.
Regards,
Mike Combs
This thread has gotten me thinking more than it did the last time it
came up. :)
and groin; it's a couple cm above the navel. (I tested this by
balancing on the edge of a peaked footrest.) And that's when my legs
are straight and my arms are at my sides. In any other pose, it's
higher.
So, imagine this: for normal horizontal flight, you have your arms
extended outward and your knees bent, so your feet are pointing
straight up. (Perhaps we attach fins to them somehow that would be
vertical in this position, helping the flight dynamics.) The wings
extend down to your hips or so to make the center of lift in this
position match your center of mass, slightly above the navel. To pitch
up, you can straighten your legs -- good for climbing or landing. To
pitch down, you raise your arms above your head -- good for diving.
Sounds pretty natural to me.
I also think that maybe we could do some useful analysis of this, after
all. Maybe not the flight dynamics itself, but at least the center of
lift vs. center of mass, for different poses. That in itself might be
interesting and helpful. We'd need a simple physics package, a model
of the human body, and a model of whatever flight suit we want to test.
Best,
- Joe
Joe Strout -- joe@...
Strout Custom Solutions, LLC
Thanks, folks. I guess it would be easy enough to attach the wings to
wherever they needed to be attached, and might even be different for
different people. The arms could still be used to provide power, even
if the wings connected to the hips. It would look different than a
lot of the pictures we see, but aerial steeplechases would still be a
doable thing.
As for the whole battery-powered, brain-controlled thing...
That's actually pretty cool, but at this point it wouldn't so much be
a "human ornithopter" as it would be a vehicle. A little less like
running and a bit more like motorcycling. Which, again, could be
pretty cool.