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Another Look at 1930's Cyclogyro Plane Design

Posted by ryuzaki0 on from the crashlo-burno dept.

trogador writes to mention that a group of researchers is taking another swing at the idea of a cyclogyro design for a UAV. Even though the cyclogyro design was invented in the 1930's there are no records of a successful flight. "Cyclogyros have the potential to be highly maneuverable flying robots due to their method of operation, making them potentially more suitable for complex tasks than helicopters and other micro air vehicles (MAVs) with less maneuverability. The biggest challenge in designing the cyclogyros is varying the angle of attack of the rotating wings. This ability would enable the plan to change altitude, hover, and fly in reverse. To achieve this quick angle variation, the researchers introduced an eccentric (rotational) point in addition to a rotational point connected to a motor."

24 of 142 comments (clear)

  1. Like a helicopter? by MobyDisk · · Score: 2, Interesting

    The biggest challenge in designing the cyclogyros is varying the angle of attack of the rotating wings. Don't helicopters have to do this too? I think it is one of the things that makes helicopters tough to manufacture. This would be cool to build, even if it wasn't a great design, just because it looks wacky.
    1. Re:Like a helicopter? by 140Mandak262Jamuna · · Score: 4, Informative

      Yes, helicopters do it too. The advancing blade meets the air at aircraft velocity PLUS velocity due to the spinning of the blades. The retreating blade meets the air at rotational velocity Minus aircraft forward speed. Thus to produce the same lift, it has to have a higher angle of attack. This is done by the cyclic pitch control. Depending on the total lift needed the angle of attack has to be increased for all the blades by equal amount. That is called the total pitch. It does make the hub mechanism of the helicopter blades very complex.

      --
      sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
    2. Re:Like a helicopter? by ericrost · · Score: 2, Interesting

      But wouldn't a cyclo-gyro not need the cyclic pitch? the variation is above and below the "wing" not side to side, so no balance issue? Honestly a question based on the 30k ft view.

      --
      My Babylon
    3. Re:Like a helicopter? by know2much · · Score: 2, Insightful

      Drag = 3 wings
      Lift = 1 wing
      Transmission Mechanism = Very Heavy
      Support Structure = Very Very Heavy
      Pressure Center (Sustentation)= Shifts
      Vibration = More than a helicopter

      Nice Try!!!

    4. Re:Like a helicopter? by 140Mandak262Jamuna · · Score: 2, Informative
      The tail rotor is needed to "anchor" the engine. If you clamp the shaft of a motor, the motor would spin in the opposite direction. Infact most ceiling fans have a fixed shaft and the motor spinning in the opposite direction. Most other applications of the electric motor has the motor bolted down and the shaft spinning. In a helicopter, how do you "bolt" down the engine? To the airframe? The whole airframe will spin in the opposite direction. That is why you need a tail rotor to provide a counter moment to keep the aircraft from spinning. You can avoid tail rotor if you have two main rotors like in a chinook, or two counter rotating main rotors. You could create a small jet using the gasturbine's exhaust and use it instead of the tail rotor.

      Why does it not generate lift in all directions? The Lift is always perpendicular to the blade/wing surface that is true. But the magnitude of the Lift depends on the angle of attack. So when the blade is in a position where you don't want lift, you can change the angle of attack and make it zero. You do it while you are swimming. Imagine the breast stroke. To move forward you have the palm pushing water back. Then you move your arms and bring it forward, but keep the palm cutting through the water without creating any force by pushing water forward. Same thing but you need to do it using a mechanism to keep the angle of attack the precisely right.

      --
      sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
  2. This is all very nice by Mr.Fork · · Score: 4, Funny

    But will it cut my lawn? Without supervision? Can I set it to keep the neighbours dog out? Lasers? Can it have lasers? Lasers would be nice.

    --
    Management is doing things right; leadership is doing the right things. - Peter F. Drucker
    1. Re:This is all very nice by JK_the_Slacker · · Score: 4, Funny

      Lasers? Can it have lasers? Lasers would be nice.

      You must be new here. Lasers go on SHARKS. Robots with lasers are SO 1980s.

      --
      I'm waiting for a "-1 somepeoplejustshouldn'tgetmodprivileges" meta-moderation.
    2. Re:This is all very nice by gurps_npc · · Score: 2, Funny
      My nephew has this really cool toy, kind of like legos, only with more definition (i.e., less block/toy like, more realisitic). Also, t attachable things com in parts, similar to how you install them. So you get the bottom of a boat, the top of a boat, a cabin, a back deck, a gun, a mast, etc.

      One of the pieces it comes with is a shark, and it has a 'connector' hole in the shark's head. It is designed to fit a 'harpoon' type attachment, so you can 'capture' him.

      But the connector is the same standard hole type.

      When I was done with it, he quite literally has a shark with a freakin laser on top of his head.

      --
      excitingthingstodo.blogspot.com
  3. Same fuel consumption as helicopters by 140Mandak262Jamuna · · Score: 2, Informative
    In a fixed wing aircraft the engines develop enough thrust to overcome the drag. Typical Lift to drag ratio is between 10 and 12 for commercial jets. Some sail planes and gliders have achieved L/D ratio of 30 and 40. In any hovering aircraft, be it helicopter or vectored thrust machines like the Harrier, or the stupid plane V22, the engines must develop enough thrust to overcome the weight. (Weight = Lift). Thus they develop between 10 and 12 time more thrust and thus they consume that much more fuel. That can not be avoided.

    Changing the angle of attack of each foil in the wing for this aircraft is no doubt complex, but even helicopters have this quite complex cyclic pitch/total pitch changing mechanisms. Given the advancement in materials and electrical actuators, it is possible that the time has come for a horizontal axis rotating wing aircraft.

    May be this craft will transition from hover to flight with locked wings more easily and more stably than that boondongle from Fort Worth, V22 Osprey. Thus for the long haul you get the speed and efficiency of the fixed wing aircraft. But you get hover ability too. The price you pay is to haul a larger powerplant all the while. But still it might beat V22.

    --
    sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
    1. Re:Same fuel consumption as helicopters by pittance · · Score: 4, Funny

      Commercial jets are at lift/drag of around 18-20 now
      As an engineer working with fixed wings it is my firm belief that helicopters fly because they are so ugly that the ground repels them - on that basis this thing is getting to the moon.

    2. Re:Same fuel consumption as helicopters by Rakishi · · Score: 2, Informative

      Basically, its current incarnation lacks both the defensive survivability (autorotate on failure) Can't it glide, somewhat, like an airplane?

      offensive armament of helicopters (all it has is a small machine gun, pointing backwards, that you have to OPEN THE DOOR to fire), Yeah because the average CH-47 Chinook or C-130 Hercules are such massive gun ships, always used to shoot at the enemy. God forbid someone just wanted to move cargo or people with a helicopter or airplane. If it doesn't have enough firepower to level a small town it's useless period.

      The current V-22 is a cargo plane more or less, it's designed to quickly and efficiently drop people or cargo where needed. It's not supposed to stay around and shoot at the enemy, most likely trying to fight back will just make it a much better target (and helicopters in general are easy target).

      trading both for a slightly higher top speed. And longer range likely.
  4. Re:Goldberg to the Rescue... by Punko · · Score: 2, Insightful

    And there's also the safety aspects when something this complicated breaks down in mid-air...but this thing will never get man-rated.

    Complicated and heavier than air like a helicopter?
    --
    If only we could fall into a woman's arms without falling into her hands
  5. Re:Goldberg to the Rescue... by Rorschach1 · · Score: 3, Informative

    Yeah, as I recall, one of the drawbacks of this design is that it can't glide like a plane or autorotate like a helicopter. If it loses power, it's coming DOWN. For a UAV that's not a big problem, I suppose.. though I wouldn't want to be underneath it.

    For that matter, a large-scale model would be a little scary to be around during takeoff and landing. I've done hover loads on a Huey (climbing in while it's hovering about 3 feet off the ground) and it still feels like the rotor's about to take your head off. Not to mention how it blows dust and gravel everywhere. This thing would be like a whirling death machine.

    Still, for a small, agile robotic observation platform, I can see where it'd be useful. But with several decades of experience with helicopters behind us, I doubt it's going to happen unless there are some VERY compelling performance differences.

  6. Re:Seeing as the link to TFA is dead ... by colourmyeyes · · Score: 2, Informative

    http://www.networkmirror.com/fDZs3ol_RaN_NoOY/www.robotworldnews.com/100194.htm

    and here's another, a mirror of the original article.

    --
    My grandmother used anecdotal evidence all the time, and she lived to be 120 years old.
  7. Re:Seeing as the link to TFA is dead ... by fewnorms · · Score: 4, Informative

    Dammit, posting the actual link would have helped here. Anyways, for the rebound:

    http://www.dself.dsl.pipex.com/MUSEUM/TRANSPORT/cyclogyro/cyclogyro.htm

    --
    Veni, Vidi, Velcro!
  8. A different link with Video! by Xoltri · · Score: 5, Informative

    http://serve.me.nus.edu.sg/cyclocopter/

    --
    -Xoltri
  9. Re:Slashdotted? by P3NIS_CLEAVER · · Score: 2

    Here is something to look at since the site is down...

    http://www.dself.dsl.pipex.com/MUSEUM/TRANSPORT/cyclogyro/cyclogyro.htm

    --
    Please sign petition to restore sanity to our banking system!!!

    http://financialpetition.org/
  10. Flying through its own downwash = bad. by goodmanj · · Score: 3, Interesting

    So one of the reasons they try to keep airplanes separated in the sky is because of the downward flow of air they generate behind them. For every action there's an equal and opposite reaction: if the air is lifting the plane, the plane must push the air down. If one plane flies too close to another, the downwash can cause the trailing plane to crash.

    The wings of this thing generate a downwash at the top of the "paddle wheel" which flows down and strikes the wing at the bottom of the paddle wheel. Not one website discussing these planes mentions this. Maintaining control and lift in this situation sounds ... challenging.

    1. Re:Flying through its own downwash = bad. by goodmanj · · Score: 2, Insightful

      I hate to pull rank here, but I have a bachelor's in physics and a PhD in climate physics, where I specialized in fluid mechanics. I'm not an aeronautical engineer, but I *have* heard of the Bernoulli effect before.

      The bernoulli effect has a bit to do with explaining *how* the wing and air push on each other, but you can understand how a plane works without any fluid mechanics at all. Gravity is pulling the plane down. There must be a counteracting force holding it up. The air exerts this force on the wings. (How? You could mumble "bernoulli" at this point, but that's more detail than we need.) Newton's Third Law states that for every action, there is an equal and opposite reaction. The air pushes the plane up; the plane pushes the air down, with a force equal to the weight of the plane.

      Airplanes *do* fly by pushing down on a bunch of air until they leave the ground. They just do it a little more subtly than a helicopter. Whether your book talks about them or not, Newton's laws always hold: if you still think I'm wrong, answer this question: "What pushes on the plane? Where is the equal and opposite reaction to that force?"

      Wing vortexes and wake turbulence are often talked about as if they're minor inconveniences, little inaccuracies in the perfect equations for wing behavior, caused by little details like finite wing length and imperfect shape. Nothing could be further from the truth. If a wing passed through the air and left it completely undisturbed, as is usually drawn in popular science articles on aerodynamics, the wing would generate no lift. How could it? If no force has been exerted on the air, no force can be exerted on the plane, and the only force acting on it is gravity.

    2. Re:Flying through its own downwash = bad. by billybob_jcv · · Score: 2, Informative

      So... I'll pull rank back - my degree *is* in aeronautical engineering. Lift is generated by an airfoil by the pressure differential between the upper and lower surfaces of the wing. The pressure differential is caused by the higher velocity of the air molecules over the curved upper surface of the wing as compared to the lower surface. A symmetrical, uncambered airfoil at zero angle of attack generates *zero* lift because the velocity above & below the wing (and therefore the pressures) are identical. That relationship between mass flow and pressure differential *is* the Bernoulli principle. Now, a pressure differential does result in a net force - that's the lift being generated. There is also a downward deflection of the airflow that results from a airfoil when it is cambered or at a positive angle of attack. However, "downwash" is exactly what the other poster described - it is the result of air spilling from the upper to the lower surface at the tip of the wing causing a vortex at each wingtip. The wingtip vortices create the "downwash" effect that causes problems for airplanes that fly too closely behind large planes. http://www.grc.nasa.gov/WWW/K-12/airplane/downwash.html

    3. Re:Flying through its own downwash = bad. by DougWebb · · Score: 2, Interesting

      If a symmetrical object is moved through the air, there will be equal displacement on each side, and no lift will be generated. A wing is asymmetric, the air traveling underneath experiences little disturbance, the air displaced around the top becomes more spread out, spreading out a gas decreases the temperature and pressure, the differential pressure between lesser displaced air beneath the wing and the more displaced air above the wing generates lift. Again, the air beneath the wing tries to fill the void created above the wing.

      Please explain how a plane flies upside down, then. They can do so for extended periods of time.

      You might want to look at http://amasci.com/wing/airfoil.html/ for a hint.

  11. The 4:30 Autogyro by slagheap · · Score: 2, Funny

    Burns: Yes, I'd like to send this letter to the Prussian consulate in Siam by aeromail. Am I too late for the 4:30 autogyro?
    Squeaky Voiced Teen: Uh, I better look in the manual.
    Burns: Ignorance!

    ... later ...

    Squeaky Voiced Teen: This book must be out of date: I don't see "Prussia", "Siam", or "autogyro".
    Burns: Well, keep looking!

    --
    First against the wall when the revolution comes
  12. Let's See Here... by Nom+du+Keyboard · · Score: 3, Funny
    Let's see here:

    The design is seventy years old.
    It has never successfully flown during all that time.
    LET'S SPEND MONEY ON IT NOW!

    --
    "It's the height of ridiculousness to say for those 9 lines you get hundreds of millions."
  13. Re:Gyroplanes today. by querist · · Score: 2, Informative

    There is a difference between the cyclogyro and the autogyro (gyroplane). The cyclogyro uses powered rotating wings to generate the lift. The engine actively turnes those rotating wings, which rotate along the sides of the aircraft.

    An autogyro, however, uses a propeller, just like a fixed-winged prop-driven aircraft, to generate thrust. The rotary wings are on the top of the craft and are _not_ driven by the engine. They are in "autorotation", which means they rotate because of the other stuff going on around them (movement relative to air d/t thrust, etc). This autorotation (one-directional clutch) generates lift.

    They are very different aircraft. The autogyro / gyroplane is well known and understood. The cyclogyro, OTOH, is a bit of an odd design. It would be interesting to see one work.