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Birds Give a Lesson to Plane Designers
Roland Piquepaille points out a news release from the University of Michigan where researchers are looking to birds and bats for insights into aerospace engineering. Wei Shyy and his colleagues are learning from solutions developed by nature and applying them to the technology of flight. A presentation on this topic was also given at the 2005 TED conference. From the news release:
"The roll rate of the aerobatic A-4 Skyhawk plane is about 720 degrees per second. The roll rate of a barn swallow exceeds 5,000 degrees per second. Select military aircraft can withstand gravitational forces of 8-10 G. Many birds routinely experience positive G-forces greater than 10 G and up to 14 G. Flapping flight is inherently unsteady, but that's why it works so well. Birds, bats and insects fly in a messy environment full of gusts traveling at speeds similar to their own. Yet they can react almost instantaneously and adapt with their flexible wings."
Current aircraft performance is limited by what the occupants can survive. Try to roll a human at 5,000 degrees per second and things would get messy.
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a barn swallow, yes, but an African swallow...
Why haven't they been looking at this all along?
Submarine designers look to fish for ideas on how to move in water.
Obviously, we're talking about a non-sustained roll rate of 720 degrees per second, or we'd have to consider an unmanned aircraft. If they do get anywhere close to the barn swallow's (African or European?) 5000 degrees per second, then it's definitely unmanned.
Other than this text, there is no discernible information contained in this sig.
So does this mean we will soon of ornithopters to defend our spice from the evil Harkonnen?
I'm sick of following my dreams. I'm just going to ask where they're goin' and hook up with 'em later.
(...and what if you're allergic to feathers? )
Quo usque tandem abutere, Nimbus, patientia nostra?
I hate commenting on another annoying stupid Roland article.
.. what's up with that?
Birds and insects have very low mass. As mass increases components have deal with more stress etc.
Post another annoying stupid Roland article when birds flying at high speeds weigh as much as an aircraft (or even a human) and then we'll see how they handle things.
Btw, I could have sworn i saw the "ohnoitsroland" tag and then it disappeared
Smaller things turn faster!! What a concept.....I'll bet if they studied flies they would find out that they turn even FASTER!!
Tolerance does not tolerate intolerance, or hypocrisy.
"...they can react almost instantaneously and adapt with their flexible wings." And they can hatch eggs and eat rocks to aid digestion.
And the problem with making a machine similarly perform is.....?
Didn't Da Vinci study birds? How is this news? Oh, wait...RP needs the ad revenue, of course.
The fact that the current crop of planes is limited to about 8-10 Gs is because that's all the pilots can withstand.
Well, if one want to survive in the nature needs to learn lessons, get experienced and live because other factors do affect one's living. So, there is no special thing in birds giving lessons to plane designers!
Perhaps they can roll that fast, and take that many G's, because that's what they have done for thousands (if not millions?) of years. Their bodies have adapted to it, as they do it almost 24/7.
And haven't we already used bernoulli's principle watching birds, and applied that to planes, getting us in the air in the first place. Has it really taken us this long to realize that we can learn how to fly better from watching the things that fly naturally every day?
I = (sum) m r^2
E = (1/2) I omega^2
It takes alot more energy to get a plane into a roll with angular velocity omega than a bird, because I is so much larger. Also, the centrifugal force dF = dm omega^2 r on the outer parts of the bird's wings and body is alot less because r never gets to be very large. Whereas the plane has to have the tensile strength to withstand this force at its outermost points with large r, and this places an upper limit on omega.
So? The Vympel R77 Air-Air Missile has a 12G limit, because it is unmanned. Humans don't really deal too well with 9+G (blackout).
We can make planes capable of doing 14 Gs but it doesn't make any sense if the pilot blacks out and crashes at 10Gs the limit for most humans. Random U
...why do so many Trekkies dress like Captain Kirk, but they never get lucky with all the beautiful alien girls?
I've calculated my velocity with such exquisite precision that I have no idea where I am.
They do make a point about the roll rate, but a Skyhawk is much more useful for migrating coconuts. An African swallow could carry one coconut at most, but they are non-migratory, so it is uncertain what sort of range they would have. European swallows are generally thought to be unable to carry even one coconut, unless two of them carried it together, but that increases the risk of mid-air collisions.
A Skyhawk, on the other hand, could carry a large number of coconuts. However, unlike with the swallows (where the main issue is not the grip but the weight ratios), the Skyhawk would be limited by the number of coconuts that could be attached. The Skyhawk is an attack aircraft with a payload of close to 10,000 lbs, which would make for a lot of coconuts. But, the only reasonable place to attach large numbers of them without causing aerodynamic interference would be the wing pylons, where the bombs usually go. If they were to fit, these coconut packages could not be much bigger than the bombs. As there are only five hardpoints, I can't imagine there being room for more than about 50 coconuts.
Still, this is a significant improvement over the swallows, and if you had to choose between the two, the Skyhawk would be a much better choice for migrating coconuts into temperate climes. Of course, something like a C-17 would be even better, but those have an even lower roll rate.
"Smaller things turn faster!! "
Geeks must get some great RPMs with their "tools".
"researchers are looking to birds and bats for insights" I, for one, am shocked.
Well, one would be that a submarine made out of meat wouldn't taste too good.
FTA: "A-4 Skyhawk plane is about 720 degrees per second. The roll rate of a barn swallow exceeds 5,000 degrees per second. "
Duh!
I'll bet that if I made a model of the A-4 the size and weight of a barn swallow, I could make it roll that fast, too.
-jcr
The only title of honor that a tyrant can grant is "Enemy of the State."
The above comment is actually insightful as it takes in the energy consideration in relation to the size into the equation.
Sometimes they come back.
Roland is off in bogosity land, as usual. The wingspan of a barn swallow is about 0.3m. The wingspan of an A-4 Skyhawk is 8.1m, which is 27x larger. So, scaled for size, an A-4 Skyhawk actually has about 4x the roll rate of a sparrow.
Historically, aircraft that looked or worked like birds have been spectacularly unsuccessful. Little ornithopter UAVs do work, but the ornithopter concept does not scale up well.
on how to recycle old news.
If you double the length of an animal (or anything else), the bird's weight increases as the cube (EIGHT times heavier). The strength-to-weight ratio decreases dramatically as it gets bigger. A bigger animal is much less strong per unit of weight.
That is why ants are able to carry so much more than their body weight. THEY ARE TINY!
You can make small buildings out of stone, but once you get to a certain size, stone is not strong enough to support the weight of the building. You need to use other building materials. This is also why the world trade center fell down. Skyscrapers are made of steel-reinforced concrete (because regular concrete isn't strong enough). Due to the fire from the fuel, the reinforcing steel began to soften, leaving only regular concrete (the steel didn't need to melt, only to soften). Once enough of the steel-reinforced concrete softened and lost its strength, it could no longer support the weight, and it collapsed.
I can't remember the source, but several years ago, a researcher in his twenties saw how owls' wingtips point upward on their downstroke. This cuts down on vorticies at the wingtips, making for a more efficient and quiet flight.
Airplane designers then took that idea and applied it to most commercial jets you see today.
Automobile manufacturers look to humans on ideas to make cars move on land...
You want fun, go home and buy a monkey!
[sarcasm] laugh...it was a joke [/sarcasm]
Looking to nature for ideas isn't exactly a lightbulb moment normally associated with professionals. 5th graders, maybe. Thus your comment, right?
Sub designers, aircraft...cars...chairs...these guys/gals are supposed to have studied things like fish, birds, trees and insects for reasons why, and why not, long before they were hired to actually build things.
http://pbskids.org/wayback/flight/feature_wright.html
This is exactly how the Wright brothers started.
Isn't an A-4 Skyhawk a bit bigger than a barn swallow?
I mean, what about the maximum load that the material can withstand?
An RC helicopter like a T-Rex 450 may run its main rotor (diameter of 70 cm == 28 inch) at 3000 rpm. Try that with a blackhawk helicopter, the wingtips of the main rotor blades would go faster than 9000 km/h (about 5600 mph), several times the speed of sound, and certainly more than the material could ever withstand...
"The roll rate of the aerobatic A-4 Skyhawk plane is about 720 degrees per second. The roll rate of a barn swallow exceeds 5,000 degrees per second. "
But can the swallow do those rolls while travelling straight up at 500mph?
Anyway the Skyhawk is a fairly old aircraft, designed in the 50's. Although they were a manouverable plane in the Vietnam war, that didn't stop them from being shot down and their pilots captured (as we will hear a lot about between now and the 1st tuesday in november...)
Couldn't they have used a modern, computer aided designed plane for a comparison?
You know how many people would throw up if they did make a 100% sucessful winged aircraft? Ignoring how messed up takeoff would be, current aircraft handle turbulence by cutting through it and minmizing it through the smallest possible air resistance and a small wing area compared to a bird. Birds just slow down and speed up and in strong gusts and float around with the wing instead of fighting it. They even go from coasting along to a dead stop in a sudden wind gust by putting their wings up and absorbing the backwards force. All that bobbing up and down and moving around and speed changes would be awful! People would be throwing up left and right! I can see it now..."Bat Airlines: For your next vacation, take the plane ride from hell...through hell!" And they could even paint on one wing "from hell" and "through hell" on the other wing. Genius! I should patent that and sit on it so nobody tries it.
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Forget making the planes act more like swallows, what they really need to work on is getting the flight attendants to swallow...
if you have curiosity of course.
Will these new planes have large talons?
This is really amusing, but least I laugh to hard allow me to enlighten some...
The mighty Peregrine Falcon, THE fastest animal in the skies, bar none, have been clocked in dives exceeding 200mph, with radar. Now that is pretty damn fast for anything made of bone, muscle and sinew and covered in something as delicate as feathers. But one has to examine the actions of the animal when it accomplishes these seemingly impossible feats of speed.
Fist of all, much like the famous ( or infamous depending on your POV, especially if you were a pilot in the early very underpowered versions ) F-14 Tomcat Naval Jet Fighter, it makes maximum use of variable wing geometry. When a Peregrine stoops ( the technical term for diving from altitude in the bird world ) its 39 to 43 inch wings fold in very tightly making the outline of the bird look pretty like a "W", leaving just enough airfoil hanging out to effect control. This reduces stress on the main wing spar ( their bones and joints ) by a huge margin thus allowing it to accomplish this feat without tearing its wings off.
Now I don't have an actual measurement of their wing span in a full speed stoop, but from photo's I estimate that it reduces wing span by a good 75% or more. The area of the wing that would comprise the distance between a human elbow and the tips of our fingers goes parallel to the body and the upper wing ( the area from a human shoulder to the elbow ) then are pulled in close to the head, further reducing wing span.
Transition from this "clean" configuration to a "Dirty" configuration after either missing or hitting its prey can be quite rapid and causes the bird to bleed off speed at a very high rate. A Falcon cannot make a "pylon" ( a turn in an airplane in which one rolls the airplane from straight and level flight by nearly 90 degrees and then applies maximum UP elevator ) turn, the force on the wings would quickly overcome the bone, tendon, muscle and joint strength. Now this is not to say the are not maneuverable in a stoop but as you would surmise their maneuverability is greatly reduced at speed. Another very interesting feature of the bird is its nostrils. Small bony tubercles in a falcon's nostrils guide the air and shock wave to prevent over pressuring the lungs and giving the bird the ability to breath while diving.
so while looking to nature can be inspiring for aeronautical design there are very real limitations in duplicating the ability of a bird with mechanical devices. Another instance would be the original Wright Flyer. It did not have ailerons, it used what is called "Wing warping" which is what birds do, but it was found to be quite impractical since the amount of wing warping required to provide the same effectiveness as a bird required that the wings be so flexible to the point of losing to much strength. Now birds do Wing warping one better as they can not only warp their wings but they can dip a wing, decrease span, warp, move their tail in all axes, and do this all at the same time, providing maneuverability that airplane designers can only dream of.
On whales and submarines. If it were not for the requirement that we a) Keep the water out of the people tank and b) be able to stay submerged for months on end, and c) carry weapons that are stand-off capable, perhaps a Blue Whale would be a decent model to study in submarine development, but not as much as one would think. One must remember that a whale of any kind is a completely articulated bit of construction. It can bend and twist in any direction thus altering its hydrodynamic profile at will. Careful study of its means of propulsion reveals that it is a "whole body" movement, not simply a movement of the flukes in an up and down motion. It was also discovered some time ago that whales overcome friction in the water by way of their blubber. Careful examination revealed that hydrodynamic pressure is relieved by the blubber and skin actualy undulating in concert with the pressure waves to facilitate their movement dow
Hey KID! Yeah you, get the fuck off my lawn!
"LIBELLE G-Multiplus® The Next Generation of Aircrew G Protection The LIBELLE G-Multiplus® The effects and advantages of the LIBELLE G-Multiplus® System Physiological effects in LIBELLE G-Multiplus® Design advantages of LIBELLE G-Multiplus® Tactical advantages of LIBELLE G-Multiplus® The LIBELLE G-Multiplus® The Dragonfly (German term: "Libelle"). The insect has extraordinarily hyper agile flying capabilities at its disposal. It protects and stabilises its organs by means of a liquid coating - and that at accelerations of 30 g. LIBELLE G-Multiplus® is a system which improves the physical power of endurance of pilots flying modern combat aircraft - making it now at all possible to exploit the aircraft in terms of the technical feasible flight characteristics. System development has been completed, tested in detail and is now on the verge of being launched on the market. The versatility of modern military jets presents maximum physical stress on pilots. With each change in direction the crews are exposed to forces corresponding to a multiple of the normal gravitational force on earth (equalling 1 g). The current generation of military jets already exposes pilots to 7 to 9 times the normal gravitational forces. As a result of these enormous forces the pilots blood is pulled into the lower half of the body. The consequences: the higher the load, the greater the danger that the pilots brain, as well as his eyes, will not be provided with sufficient oxygen; that leads to Grey-Out (loss of the ability to identify colours), followed by tunnel vision (limited vision). The next step is Black-Out, a complete loss of vision. The most extreme consequence due to insufficient oxygen supply to the brain is g-LOC, the gravity induced loss of consciousness. This circumstance is fatal for the aircrew in the majority of cases. Last but not least, high or long accelerations lead to extreme pain in the arms and legs which can be hardly tolerated. The performance potential of modern combat aircraft of the third and the fourth generation (e.g. Eurofighter Typhoon, F22 Raptor, JAS 39 Gripen) cannot be fully exploited, as they expose the pilots to an extremely high g-load. In particular, g-onset rates in combat aircraft of the fourth generation can be as high as 20 g per second, i.e. the pilot and the aircraft reach the maximum permissible acceleration of for example 10 g in less than half a second. The physiological threshold and stress level of the pilot therefore currently represents the weakest link in the man/machine interface. Thereby he is unable to fully exploit the combat effectiveness of modern military jets."
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I'm wondering where the DoaBarrelRoll tag is.
It is interesting research, and no doubt useful; millions of years of in-the-field generic trial and error can't be dismissed.
However, unless we're talking unmanned vehicles, I'd think a serious limitation in any design is the not-designed-for-flight blob of human goo sitting in the cockpit. You can strap pressure pants on to stop them from blacking out in higher G's than normal, but in general, our physiology is not tailored to the stresses of flight that birds can achieve daily. We're a ground-based entity rattling around inside a rigid hole inside the flying machine; it hardly could ever compete to with an entity whose every organ and tissue has evolved with millions of tweaks towards better flying (and thus better survival through preying, mating, escape, etc.)
Another factor is that almost all of our successful (but relatively brief) engineering history has been based upon solid, fixed objects (with the odd hinge, wheel, sliding groove, where motion is required). Okay, we need the plane to change course, we'll add a couple of hinges between rigid parts on the wings and tail (a pale imitation of the flexibility of a bird's wing). We have very little in the dynamic, flexible materials that are as strong, lightweight, and controllable as birds possess. It's amazing we do as well as we already do, considering the inflexibility and weight of our materials. (On the other hand, it always amazes me how efficient birds are; with what little they seem to eat, they can fuel incredible amounts of flight time; I guess they only have to keep a few ounces aloft, although it still impresses me.)
Love many, trust a few, do harm to none.
Round my way, they call them a babymother - if you're lucky, you get one as a wife.
What's with the sudden outbreak of 'nigger' trolls, anyway?
Was about 2001 when the last one happened - have the trolls got a 7 year itch, or what?
One swallow does not a fellatrix make
if mother nature was a patent house she would sue most of today's technology company's. we scientists have made so much "inventions" based on things found in nature (helicopters, synthetic oil, camera's, walking robots, and so on). I guess if she filed all patents when the patent system started she would be filthy rich, then again ...greed and the use of money are our inventions ;)
Ornithopters are 0/2 Flying Artifacts, so they don't have any offensive capability as they are...
Ah, sorry, wrong geek-culture.
Meta will eat itself
I'm not a plane designer but bird's gave me a lesson once, it was about not parking under trees.
I will have a sig when the market demands it.
...presumably those birds from which said lessons about flying were obtained did not include any ostriches?
Gentoo Linux - another day, another USE flag.
Birds Give a Lesson to Plane Designers
By crapping on their freshly washed cars?
Shop as usual. And avoid panic buying.
wings?
N.
Electronic Music Made Using Linux http://soundcloud.com/polyp
Bad economic situation. Unable to criticize current economic system since it's taken as god-given. Scapegoat needed to blow off steam.
People have been learning about Aerospace Engineering from birds for centuries. What do you think was the inspiration for the Wright brothers "wing warping" technique? The perfect aircraft has always been a bird. The only think I see that's new here is exactly why that is.
Efficiency is almost always more unstable and stability is almost always achieved at the expense of efficiency.
Take for example forward swept wings. More efficient, but less stable.
More common concepts like dihedral, the higher the angle the more stable, but the less efficient.
Guess what those "inert bombs" were
[oh, and to answer your question: empty weight is about 11000 lbs; max takeoff weight is 24500 lbs.]
Cats have a smaller turning radius than an F1 car.
It's a bird! It's a plane! It's...it's...ohnoitsroland.
Repeat after me: mass increases as a cube of size (LxWxH), while strength increases only as a square of size (cross-section, LxW). Double the size of something without using stronger materials and it won't be able to withstand the same things as the smaller version. Since there's some limit to the strength of materials, at some point the larger one cannot be made as strong as the smaller.
Of course with the mongoose you would get quicker reflexes...
We're in college now. There's girls here. They do stuff....
This entire entry makes me think of the Douglas Adams (RIP) bit on the sperm whale falling towards the planet surface..
"I wonder if it will be friends with me?"
"Birds Give a Lesson to Plane Designers"
So, we've been flying planes for around 60 years and finally we've turned to the fucking BIRDS for design tips...
PS: NO, I haven't read TFA, or even TFSummary for that matter. I'm just pointing out that this might be a case where the headline could have stood to be a little more descriptive... or accurate or something.
Weren't birds the ORIGINAL inspiration for flight, which means that we have ALWAYS looked to "birds and bats for insights" in aerospace engineering? This fact makes this article outdated by centuries. There is sooo nothing to see here - move along.
In other news, a 45 kg karate expert gives lessons to a 485 pound Midwesterner. It isn't going too well.
The accelerations experienced by birds and planes alike are not "gravitational" as TFA suggests, but due to curved flight. "Gravitational" acceleration stays more or less constant at 1G.
is Cats' Paws and Catapults: Mechanical Worlds of Nature and People, which compares and contrasts the mechanical principles behind natural and human mechanisms. One important point is that these principles very often do not scale very well at all. Comparing a swallow with a jet fighter is just silly. A swallow as large as a jet fighter would never hold together at the rotational rates a standard version could achieve, and a wee tiny jet fighter would have a much easier time of spinning faster. The article might have said this, and it's only a misleading summary, but that's the way it goes on slashdot :)
Those people who think they know everything are a great annoyance to those of us who do. (Isaac Asimov)
I'd say it's much easier to accelerate the swallow to Mach 2 if you throw it *into* the jet engine.
Scientists have been looking to birds for thousands of years to figure out how to fly. Most of the time, it didn't help them.
"posts" from folks like Roland are getting more and more common. It's often a stretch to come here, as it is. I find as my respect for /. lessens, I come here less often.
So how much DO you have to pay to get your dumb post onto slashdot's front page? Seriously.
expandfairuse.org
Each pylon is capable of being fitted with an MCBR - the Multiple Coconut Bomb Rack (later re-named by some pencil-pusher to the Multiple Carriage Bomb Rack.)
Well, it makes sense... Much as an African swallow can grip a variety of fruits by their husk, so to can a variety of fruits be carried by the A4's bomb racks. The original name was from before they made use of this fact and were only carrying coconuts.
The enemies of Democracy are
Why can birds, bats and insects do all those crazy thing a plane can do? It has nothing to do with their design, its a common phenomenon often called "Scale Effect". Its like why I can do loops, rolls, stalls, inverted-flight in a remote-control Model DC-10, that could never, ever be done in a real one. Or why smaller animals have higher heart rates, and blink faster than larger ones.
Things like momentum, angular momentum, and "scale" speed do things you wouldn't intuitively think.
One of my favorite thought experiments involves a ten-thousand foot-tall giant. If he jumped down from a platform that was only "knee-high" - his entire body would crumple like a demolished building on impact.
Experiment: Take a matchbox car, pick it up in the air - let's say 10 times its normal height, and drop it on its roof. What happens? Do the same with a real car. What happens then?
Conclusion: Automotive engineers need only to look to the good people designing Matchbox cars to learn how to improve safety and strength of vehicles
May be a redundant post. I don't have time to read hundreds of posts. Sue me. :)
These sorts of numbers are completely bogus. You can study swallows, but the lessons will
only apply to flying vehicles about the same size as swallows. You can't rationally compare
a swallow to an A4 skyhawk any more than it makes sense to study ants to learn about Elephants.
Both pairs of objects move in similar ways, but when you change the scale, the square cube law applies