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Another Ornithopter Takes Off
mnmn writes "Ornithopters have been around for a while, but a professor at the Toronto Institute for Aerospace Studies has made progress with his. It flew for 14 seconds and covered a third of a kilometer. However it landed with a bit of a crash. Interestingly it uses a glow jet turbine from RC aircraft."
As far as I was aware model jet turbines run on Kerosene, just like their bigger brethren. Glow fuel is Nitromethane mixed with a lubricant such as Castor or Synthetic oil.
The gift of death metal does not smile on the good looking.
Someone flapping about something worthwhile!
Task Mangler
Cool!!! Can't wait for those charter flights to America on Boing Ornithopters... I wonder what kind of drinks they offer...
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I wonder if one problem is birds wings, while they do flap, they do not have a rigid shape, they change shape durring flight.
I wonder if an ornithopter could work with a wing that could change it shape slightly.
of course I am still not sure, is there an advantage to an ornithopter or is it just a curiosity thing?
A Smith & Wesson beats four aces -- Murphy's Law of Poker
These things really didn't help Paul.
My friend invented a flapping paper airplane 20+ years ago in junior high. Of course it's not nearly the same, since it reacts to pressure fluctuations instead of creating them. There are (pdf) instructions so anyone can be an ornithoptrix.
A slashdot article that is
1) Interesting
2) NOT and infomercial or astroturf
3) Has a paragraph to page ratio of greater than 2
4) Has some modicum of detail
5) Not about SCO, Apple, Google or Mr. Bill
Congrats. Of course, the signal to noise ratio is still painfully small. But it's a start.
Faster! Faster! Faster would be better!
My friend had been an engineer on the flapper project for years and it was only recently that the booster was added. As far as I understand, the wings do flex and have successfully propeled the plane on the runway to significant (~60kph) speeds without need for a boost, however, the plane kept oscillating into the ground. More than one interesting test day was the result. All I can say is "congratulations" to those on the flapper team...its been a long time coming. :) (I hope there will be an alumni party for those who have put so much effort into this project over the years.)
The professor's website is being hammered by us, so I've only got the Star article to go from. "The R/C turbine provides thrust to get up to takeoff speed, at which point the flapping wings take over." I didn't see mention of a secondary propulsion means that causes the wings to flap. Electric motor? Pedal power? Briggs & Stratton? I'm curious how much horsepower it takes to keep his bird aloft. Anyone know?
I doubt anybody would like to sponsor it. As everyone is working on getting things cleaner, this seems like a feul gusler.
Nobody should stop dreaming though, they should open a donation page and print names on the wings!
A bird's wing is an aerodynamic lifting body, and model ornithopters were flying before the Wright Brothers. They don't "fight against the lift" of the wing, but use it in a pretty sophisticated way.
We don't have human-carrying ornithopters because scaling effects get in the way. The ability of a wing to produce lift (and the muscle power available to it, in the case of a bird) goes up as the square of the size, but the weight goes up as the cube.
This is what limits the size of birds. A hummingbird can fly all day, even hovering motionless. A robin needs to rest once in a while. An eagle can only fly under muscle power in bursts; most of the time he has to soar on rising thermal currents like a sailplane. An ornithopter big enough to carry a human is going to need a LOT of power.
rj
It flew for 14 seconds [...] However it landed with a bit of a crash
Is that their server being slashhunted that they're talking about ?
I have discovered a truly marvelous proof of killer sig, which this margin is too narrow to contain.
I suspect that this can be chalked up to the proportionatly enormous wing muscles these birds have, which is why ducks and geese are sought after game birds. They have tons of white meat compared to, say, a crow. They also have a relatively long wingspan for their weight, I think.
Also, migratory birds don't fly the whole way from Canada down south in one go. They often stop to rest and refuel (and crap on my car).
I'm no ornithologist, but these seem like logical deductions. Could be wrong.
All logical conclusions. When anything migrates, it has to stop and refuel and rest eventually. Also, it's not like there's one bird flying his ass off for 3000 miles all by himself. Ever notice the reverse V formation geese use when migrating? It's the most efficient formation for distance flying. The lead bird does most of the work, and each bird in sequence behind the lead does less and less work to stay aloft, because they're in a drafting chain. The birds at or near the back of the V are working the least while the lead works the most. They often rotate the lead bird out from one of the rear birds.
Another advantage ducks and geese have is that they are able to build up great fat reserves which is converted into energy for long endurance flight. Simply compare the meat of a chicken to the meat of a duck and it becomes obvious which one has more fat content. Ducks and geese also need these fat reserves to survive colder climates for short periods of time as well (pre-migration).
You're correct on your point of wingspan/size ratio of ducks/geese/swans. It seems the longer a bird must fly the greater the wingspan is needed. See the albatross for the best example of this. They have a wingspan of up to 11' 11" (no that's not a typo, 11 feet 11 inches total wingspan).
There are three posts describing what glow fuel is, they are all somewhat different, and they are all modded to 4 or 5 points as either informative or insightful. Who is the winner?
And is this post funny, insighful, informative, or is it just off topic?
RTFM; please, I beg you.
Incidentally, you can buy some pretty neat ornithopter kits from www.ornithopter.org. I'm not affiliated or anything, just interested in flapping-wing flight and experimenting on a small scale.
The development of flapping wing flight is interesting because it can also have other applications. I am especially interested in the use of 'flapper' designs in water craft (specifically for use in robotics). An interesting use of similar tech can be seen in these kayaks. Intersting stuff.
Real nerds thought of Dune.
Basically, white meat stays white because farmers clip their chickens' wings to keep them from exercising those muscles much.
The more a muscles is exercised, the darker the meat gets.
[Fuck Beta]
o0t!
Precisely. We already have flapping-wing aircraft, and they fly much more efficiently than birds because we know how to make a rotating joint and nature doesn't. Consequently we flap with economical rotary motion instead of energy-wasting reciprocating motion.
There's a project at Boeing to create a hummingbird-like propulsion system. It says, "Flapping flight may be the wave of the future for aviation." Their system relies on a shape-memory-metal actuator muscle. I'm forgetting at the moment who but there was another group recently that had a big announcement about simulating muscle with shape memory metal systems.
Obviously this is still R&D, but flapping doesn't seem to be down and out just yet. (BTW, I looked it up and a hummingbird wing is just shy of 180 degree rotation with 75% of the lift from the downstroke and 25% of the lift from the upstroke). Energy consumption is high, so portable fusion generators might be a necessary prerequisite for heavy craft.
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OUTSIDE_IP=$(dig +short my.ip @outsideip.net)