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Da Vinci's Ornithopter Prepares For a Test Flight

Dirak writes "Over 500 years ago, Leonardo da Vinci conceptualized a self-powered flying machine that would achieve both lift and thrust with flapping wings alone and named it the "ornithopter". Hot on the heels of the 100th Anniversary of the Wright Brothers flight, and the recent X prize, a team of scientists from University of Toronto's Institute for Aerospace have taken on this challenge to make Leonardo's dream a reality."

24 of 213 comments (clear)

  1. Yesterday's tomorrow? by semifamous · · Score: 4, Interesting

    I remember reading the Dune series a while back and I had to pull out a dictionary to look up what an ornithopter was. Wouldn't current technoloy be a lot more efficient?

    1. Re:Yesterday's tomorrow? by Anonymous Coward · · Score: 4, Funny

      Handy things dictionaries. That's the last time I'll go to a ornithologist for a check-up!

    2. Re:Yesterday's tomorrow? by moniker · · Score: 5, Interesting
      from the site:

      However, the challenge of achieving both efficient lift and thrust with flapping wings was far greater than simply using the wings for lift and providing thrust with a separate propulsor.

      Isn't current technology all about brute forcing things? Efficiency takes time. It's easier to just throw power and money at a problem. Like the excellent example I saw somewhere about how Arches are more efficient, but most of our construction (except for bridges and the like) are based on stronger materials and shapes that aren't as likely to give us headaches.

    3. Re:Yesterday's tomorrow? by Anne+Honime · · Score: 5, Informative
      Wouldn't current technoloy be a lot more efficient?

      Probably, but you never know... plus carftsmen of the past had shared secrets which got mostly lost over time (blame wars, plague, etc.) as how to build very light and yet solid structures out of wood (and eventually, stone). Think about european cathedrals. Most of them were made without any blueprint. That's truely wonderful. Re-building a working replica sometimes is the only way to go to get back that knowledge. I once saw a documentary on our Discovery channel's sibbling, about the making of a middle-age catapult. The first real life attempts broke themselves into pieces until they managed to understand archeological evidences and set all ratios back to what they once were, and then put the thing on wheels which were not used to carry the weapon around (as was unanimously beleived), but to handle the recoil. Then, they achieved pretty nice accuracy out of what was thought to be a primitive device.

    4. Re:Yesterday's tomorrow? by nine-times · · Score: 4, Insightful

      True. The beliefs that people of the past were primative know-nothings and that we are now on the verge of knowing everything are both highly overrated.

    5. Re:Yesterday's tomorrow? by kfg · · Score: 5, Interesting

      . . .are based on stronger materials and shapes that aren't as likely to give us headaches.

      Or backaches. You can make an arched bed from a sheet of quarter inch plywood. Very efficient use of materials, but you aren't likely to want to sleep on it, and efficiency in materials is not the most important parameter of a bed.

      Sometimes the shape itself is the most important factor. That's why domes never took off for personal housing. It's an efficient shape for everything but living in.

      You'll note that cars, boats and airplanes all use the arch extensively (the panels on your car all have at least a slight curve to them for a reason), because in the case of these structures efficient use of materials is a critical factor.

      And as it turns out seperate systems for thrust and lift in a flying machine are more efficient than using one system for both, that's why it's so hard to build an ornithopter and why aerotecnology didn't get "off the ground" until that was realized.

      The reason nature has adopted the flapping wing is simply because it cannot emulate a shaft unidirctionally rotating in a bearing in a biological structure, so it had to "make do."

      A wheel on an axle is notoriously more efficient than these "legs" things.

      KFG

    6. Re:Yesterday's tomorrow? by Merkuri22 · · Score: 4, Insightful

      A wheel on an axle is notoriously more efficient than these "legs" things.

      Until you try to go up stairs. DARPA is working on building dog-like robots with legs to carry a soldier's gear. Wheels are good only on flat surfaces. Ever try to push a wheelchair up a rocky slope? They make wheelchair ramps for a reason. Sometimes nature DOES get it right.

    7. Re:Yesterday's tomorrow? by kfg · · Score: 4, Interesting

      Oh, nature almost always "gets it right" within the parameters of the problem, or at least right enough to get the job done, which is not always the most efficient in engineering terms (the tail of the peacock works, in part, because it is not efficient).

      I did not in any way mean to denigrate the solutions that nature finds, only to point out that the solution set is inherently limited.

      An airplane only needs to fly, a duck has to perform many more functions (such as making more ducks), thus rigid wings may prove to be unworkable over all, despite the fact that the rigid wing is more efficient when one looks strictly at the issue of flying.

      However, thank you for your post. It has given me pause and I may have to go back and redsign my "most fearsome killing machine in the universe."

      KFG

  2. About time by BlueThunderArmy · · Score: 5, Interesting

    Wow, I'm actually rather shocked nobody's tried this before. It's a famous bit of trivia that da Vinci "invented" the helicopter, it was only a matter of time (~500 yrs) before somebody set his theories into practice.

    1. Re:About time by semifamous · · Score: 4, Interesting

      They have tried it. Lots of people tried making planes that flew by flapping their wings instead of using flaps and rudders to control their direction. You'll generally find clips of these attempts in the comedy section...

    2. Re:About time by BlueThunderArmy · · Score: 5, Funny
      Why is it so shocking? There is really no need for this.
      This is a pretty shocking reaction from a member of Slashdot community, which likes to do useful things like installing Linux on a Gamecube.
  3. Some limitations that have to be worked out by Anonymous Coward · · Score: 5, Funny

    Currently, only pilots made of balsa wood can fly this thing.

  4. Buy your own right now. by G4from128k · · Score: 4, Informative

    We have one of these toy ornithopters and it flies quite nicely. Its use of a leading-edge rigid spar and loose mylar wing material make the wing form a semi-efficient shape on both the up and down stroke.

    --
    Two wrongs don't make a right, but three lefts do.
  5. Whaa? by The-Bus · · Score: 5, Funny

    Why bother even casting it? Sure, it's 0 Mana, but it's still a 0/2 Flying Artifact. Give me a break. What are you gonna do? Enchant it? Oooh, don't hurt me.

    Oh wait, you mean in real life. Ahhhh.... *whistling*

    --

    Small potatoes make the steak look bigger.

  6. Is it going to work THIS time? by Anonymous Coward · · Score: 5, Informative

    Back in September, they tried to make it work but it didn't get very far at all...

  7. Leonardo, not Da Vinci by bickle · · Score: 5, Informative

    The proper name to use is "Leonardo", or "Leonardo Da Vinci", not "Da Vinci". That's like referring to someone as "of Dallas".

    1. Re:Leonardo, not Da Vinci by Anonymous Coward · · Score: 4, Funny

      This is very true. My buddy Ralph Da Vinci goes on rants about this all the time.

    2. Re:Leonardo, not Da Vinci by The+One+and+Only · · Score: 4, Insightful

      You name another notable historical individual known as "Da Vinci" and I'll grant your point.

      --
      In Repressive Burma, it's not just your connection that dies. slashdot.org/comments.pl?sid=314547&cid=20819199
  8. This group has tried before, IIRC by jd · · Score: 5, Insightful
    The machine nearly shook itself to pieces. Since the attempt was covered by Slashdot, I'm surprised no posters have mentioned the earlier attempt. If they've fixed the structural issues, this should be a fascinating demonstration.


    Yes, "modern" technology is more efficient, but this does a great deal to teach us about structural engineering in highly unconventional designs. I doubt Ornithopters will ever be popular (except maybe as a sideshow at larger fairs and airshows) but as a case study for engineers... It would be superb!


    Engineers at schools, colleges and even some Universities tend to build "nice, safe" projects. Stuff that teaches you how to bolt things together - if you're lucky. A good project should be hard enough that engineers are going to fail at least once, because you learn far more by failing - and more again by catching problems before they turn into failure.


    It is obvious now that Ornithopers are hard engineering problems. As such, even if they have no other value, they would make superb educational devices.


    Inventions like this are never wasted - only opportunities can be wasted.

    --
    It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
    1. Re:This group has tried before, IIRC by jd · · Score: 4, Insightful
      Exactly. And while a lot is known about both theory and practice of conventional aircraft wings, rather less is known about, say, insect wings. It's only recently that people started putting butterflies in wind-tunnels, for example. And those are vastly simpler than, say, a dragonfly, which can hover or fly backwards perfectly well.


      Our understanding of larger animals isn't a whole lot better. Sure, we know the muscles involved in a hummingbird's amazing flying abilities, or those of kestrals. (Again, both of these can hover and fly backwards.) We can run simulations on computers to see air-flow. Well, if you happen to have a spare super-computer in the attic, that is.


      But the actual mechanics of such systems? To the point where an engineer could go out and build a duplicate? Even a small robotic device, such as the spy drones you mentioned? Maybe, but I'd be impressed if they could achieve a fraction of the efficiency of nature, at this point, or a fraction of the aerodynamic flexibility.


      Even if the DoD or some other TLA'ed Government agency could do it, I believe that these are perfect engineering problems for all engineers at all educational levels, precisely because of the "weird mechanisms" involved. Low-altitude hot air balloons are trivial. Straight-wing gliders are nearly trivial, once you know the shape of an aerofoil.


      Insects and some of the stranger birds... Ah, now that kind of engineering is really tough.

      --
      It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
  9. I've seen this thing on Discovery before by asoap · · Score: 4, Interesting
    I've seen this thing on Daily Planet. It's a Discovery Canada science news show. They did a little piece on this thing. When I saw it like 4 months ago, the thopter was almost ready to get off the ground. The showed it running down the runway, and it was bouncing off the ground. As the wings came down, it would actually pull the wheels up, and as the wings went up, the wheels came down. It was pretty funny, but you could tell that this thing just needed a little more balls to get into the air.

    Also when they interviewed the professor, he was saying that a thopter could potentionally be much more manuverable then a traditional air plane, which was one of the reasons why he was building it.

    -Derek

    --
    Treat me like a marketing stat, and I'll treat your movie like a series of ones and zeros
  10. Nature HAS developed a rotating shaft in a bearing by xmark · · Score: 4, Informative

    (From the previous post...) "The reason nature has adopted the flapping wing is simply because it cannot emulate a shaft unidirctionally rotating in a bearing in a biological structure, so it had to make do."

    Au contraire. Mother Nature is one hell of an engineer. I remember reading about the design of bacterial rotary flagellae in Scientific American a few years back, and marvelling at the elegance of the motor.

    Here's an article from Wikipedia that describes it pretty well (excerpted below).

    The filament is composed of the protein flagellin and is a hollow tube 20 nanometers thick. It is helical, and has a sharp bend just outside the outer membrane called the "hook" which allows the helix to point directly away from the cell. A shaft runs between the hook and the basal body, passing through protein rings in the cell's membranes that act as bearings.

    The bacterijjkklellum is driven by a rotary engine composed of protein, located at the flagellum's anchor point on the inner cell membrane. The engine is powered by proton motive force, i.e., by the flow of protons across the bacterial cell membrane due to a concentration gradient set up by the cell's metabolism (in Vibrio species the motor is a sodium ion pump, rather than a proton pump). The rotor transports protons across the membrane, and is turned in the process. The rotor by itself can operate at 6,000 to 17,000 rpm, but with a filament attached usually only reaches 200 to 1000 rpm.

  11. Re:Insect Flight = More efficient... by mks180 · · Score: 4, Informative

    The method employed by an orthithopter to generate lift and propulsive force is very different than what an insect uses. This is how I understand it: because of the small Reynolds numbers or ratio between the aerodynamic forces and inertial forces of the wings, the air seems a lot more viscous to an insect. It doesn't produce lift in a traditional sense that a bird or an airplane does. As its wings flap, the motion generates a vortex and the spinning motion of the air produces low pressure inside the vortex. During each stroke of a wing, the flapping motion of the insect is such that the vortex moves across the upper surface of the wing. This vortex imparts a large pressure differential between the lower and upper surface. At the scale of an insect, the amount of lift produced is much larger than what you could produce by having a stationary wing with an airfoil-type cross-section. But it doesn't efficiently scale up to anything larger than a humming bird, at least not in air. You'd need a denser, probably more viscous gas/fluid. I've seen mineral oil used as a medium to study mechanical equivalents of insect wings since it's density and viscosity lets you slow down the time scale.
    I've been to a presentation by the professor in charge of the ornithopter program. They did some amazing research to figure out how to make this concept work. It has to do with correctly coupling the elastic flapping motion of the wings with twisting motion. But unlike an insect, lift is produced by the forward motion of the aircraft, just like in a normal airplane. The thrust is produced by the flapping and twisting motion pushing the air back.

  12. This is incorrect! by THESuperShawn · · Score: 4, Informative

    From the FA..."However, until now, most attempts to fly by flapping wings, either using human muscle or mechanical power have failed." OK, argue "most" with me if you want, but..... There are readily available R/C kits that do just this. I am not talking about those stupid "TIM" birds that you wind up and they flap around like they are having a seizure, I mean a real "R/C ORNITHOPTER". Here is a link to videos of one of the MANY models available. http://www.jgrc.biz/en-us/pg_25.html While the full-size project is definately cool, I think they are overstating it a bit. This design HAS been made mechanically possible well before now.

    --
    Repant. Thy end is sheer.