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Another Look at 1930's Cyclogyro Plane Design 142

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."
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Another Look at 1930's Cyclogyro Plane Design

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  • Like a helicopter? (Score:3, Interesting)

    by MobyDisk ( 75490 ) on Monday October 29, 2007 @02:43PM (#21159803) Homepage

    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.
    • by 140Mandak262Jamuna ( 970587 ) on Monday October 29, 2007 @02:55PM (#21160001) Journal
      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.
      • Re: (Score:3, Interesting)

        by ericrost ( 1049312 )
        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.
        • They do have the same issue. In a helocopter, the advancing and retreating blades are on the right and the left. In this it is on the top and bottom. That is all.
          • In a helocopter, the advancing and retreating blades are on the right and the left. In this it is on the top and bottom.

            Yes, but in a helicopter, the left-right asymmetry would flip it out of control if not corrected. This thing's top-bottom asymmetry doesn't need correction, just proper alignment with the center of gravity. If it changed with speed, it might need some correction, but it is nothing as vital as thehelo's left-right asymmetry.
            • Yes, but in a helicopter, the left-right asymmetry would flip it out of control if not corrected.

              I thought the helicopter would spin out of control without a stabilizer. The stabilizer servers to pull the tail in the opposite direction the blades want to pull the helicopter.

              Airplanes and helicopters generate lift by creating a vacuum on a wing or blade that's perpendicular to the ground of course.

              What I don't understand about this gyrocopter thing is how the spinning wings don't generate force in all directions - that is when the wing is on the bottom why doesn't it get pulled down? Or when it's on

              • Re: (Score:3, 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
                • The difference in this case is that this setup has two rotors rotating assumedly the same speed, and both sides will produce the same lift regardless, even if you DON't have cyclic controls.

                  The complex cyclic setup would be very helpful though, allowing al those neat hover/backup/banking w/o changing rotor RPM features.

                  This setup should be far more efficient at high speed as well.
          • by hey! ( 33014 )
            Well let's say its the same phenomenon, but not the same issue. A stalling retreating blade in a helicopter causes the aircraft to roll, causing a failure of controlled flight even though the advancing blade is generating enough lift to support the aircraft. In a cyclogyro, it is conceivable that stalling lower blades would not have such a catastrophic effect, since the advancing blades on both sides of the aircraft are generating plenty of lift.

            Or the whole thing might shake itself apart like a piece of
          • by mangu ( 126918 )
            But in a helicopter there are no wings moving across the airstream, like the wings do when they go up and down in the cyclogiro. Also in a helicopter the centrifugal stress is along the length of the wings, which tends to straighten them, in the cyclogiro the centrifugal force will bend the wings, they would have to be stronger (and heavier) to compensate.
    • Re: (Score:2, Insightful)

      by know2much ( 37539 )
      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!!!

      • Drag = 3 wings
        Lift = 1 wing

        More like Lift = about 2 wings average. By changing the angle of attack you can get lift on both the forward and reverse parts of the cycle. (Even if you DO bend the airfoil from a symmetrical shape to improve its lift-drag ratio for one direction at the cost of reducing it for the other - which you still might want to do if the vehicle spends most of its time going "forward".)

        A three-blade/rotor cyclogyro has about the same math as three-phase power, by the way. It's a bit les
  • by Mr.Fork ( 633378 ) <edward.j.reddy@[ ] ['gma' in gap]> on Monday October 29, 2007 @02:44PM (#21159823) Journal
    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.
  • Interesting concept. I'm wondering if they can get past the weight that the machine's complexity will add. And there's also the safety aspects when something this complicated breaks down in mid-air. Course, who cares about a robot, but this thing will never get man-rated.
    • Re: (Score:2, Insightful)

      by Punko ( 784684 )

      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?
      • Complicated and heavier than air like a helicopter?

        Looks to be an order of magnitude more complicated than a helicopter. Otherwise, this thing woulda flown already.

    • by Rorschach1 ( 174480 ) on Monday October 29, 2007 @02:52PM (#21159955) Homepage
      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.
    • by blhack ( 921171 ) *
      Yeah, good thing those helicopters never got "man-rated"...that would be a disaster!

      "man-rated"...i think I'm going to start using that in totally in-applicable situations:

      Guy: "Holy shit Ryan, this server weighs like 300 lbs!"
      Me: "Yeah, dude this thing is fucking MAN-RATED!"
  • Can Cyclogyros autorotate [] like helicopters? I suspect that they can. I have seen plans for model "airplanes" that are spinning cylinders of airfoils. This would make them a lot safer. (Or give an option for a safe recovery mode of a robot in case of engine failure.)

    Lots of Google Entries [] but no Wikipedia []
    • Or give an option for a safe recovery mode of a robot in case of engine failure.
      Parachutes and balloons, similar to what the Martian lander had, would be pretty good for aiding in a safe recovery.
      • That would be lots of additional weight. Also, if Cyclogyros can hover or fly at very low speed, this wouldn't be an option. In many cases, there wouldn't be enough time for the chutes to open. You'd want some way of utilizing the rotational energy already stored in the rotors. Throwing that away is wasting a valuable resource in an emergency.
        • I don't see why this wouldn't be a candidate for something similar, assuming autorotation isn't an option. Basically, there's a small rocket (or charge, I don't remember which--it's been a while since I was interested in the ultralight scene) that violently extracts the chute from the container and makes it possible for the chute to open even at very low speed/altitude.

          They can't be that much additional weight if they're being installed in what are essentially hang gliders.
          • For heavier aircraft, this is still not an option. Also, they still might not help for hovering at very low altitudes. I don't know of any ultralights that hover. (But let me know if I'm wrong!)
            • NASA used both to get machinery on Mars, and they had to launch the added weight out of Earth's gravity. Surely it can't weigh too much.
              • NASA? You also get into trade-offs with expense. (Especially the airbags.) I hope you're right and those things appear as safety options for small aircraft and not just ultralights, but I doubt it. It still doesn't do you that much good at fairly low altitudes where the chute has little time to open but are still high enough to be deadly.

                My coworker are doing a VTOL RC model project, and we've talked about a chute from an Estes rocket kit. But I doubt we'll be using it.
        • If you have something light and unmanned flying low, I would think it more effective to deploy airbags than parachutes...or just an explosive charge, since you would probably rather prevent than assist recovery on reconnaissance missions.
    • I think we could design a mechanism to lock the rotation out and lock the foils at specific angle of attack to make the whole contraption glide.
      • If Cyclogyros can hover or fly at very low speed, this definitely isn't an option. You wouldn't have enough forward velocity to generate lift. At low altitudes, this could easily be disastrous. You'd want some way of utilizing the rotational energy already stored in the rotors. Throwing that away is wasting a valuable resource in an emergency.
  • by 140Mandak262Jamuna ( 970587 ) on Monday October 29, 2007 @02:46PM (#21159869) Journal
    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.

    • by Anonymous Coward
      Tell us what you *really* think about the V-22 Osprey...
    • by pittance ( 78536 ) on Monday October 29, 2007 @02:58PM (#21160055) Homepage
      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.
      • they are so ugly that the ground repels them

        Oh damn! And all this time I thought levitation was my mutant super power. Turns out that it's my face that is my mutant super power. :(
      • it is my firm belief that helicopters fly because they are so ugly that the ground repels them

        It is rare that I laugh out loud while reading Slashdot. This comment made me do it. Well done! In fact... clickty-click...
      • by RM6f9 ( 825298 )
        Helicopters do not fly - they merely beat the air into temporary submission...
    • ... or the stupid plane V22, ... that boondongle from Fort Worth, V22 Osprey.

      Why the animosity against the V22? [] Is it Bell's execution of the design, or the design itself?

      Granted, making the V22's rotor large enough to support hovering leads to a vastly over sized propeller in forward flight. Other than that, it sure seems to me, executed properly, a tilt-rotor truly gives you the best of both worlds. A VTOL aircraft [] with the speed of a fixed wing has long been a dream of aviation, especially the m
      • The hatred for the v-22 isn't from the design, it is from the number of serious flaws which remained in the final project, that would have sent it back to the drawing board if there hadn't been so many pork-barrel contracts on the line. Basically, its current incarnation lacks both the defensive survivability (autorotate on failure) and offensive armament of helicopters (all it has is a small machine gun, pointing backwards, that you have to OPEN THE DOOR to fire), trading both for a slightly higher top spe
        • Re: (Score:3, Informative)

          by Rakishi ( 759894 )

          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, mo

          • Can't it glide, somewhat, like an airplane?

            It can glide just fine, if it loses power while in horizontal flight mode. The problem is that it is most likely to get hit on approach (props pointed up) -- which will make it drop like a rock.

            It's not supposed to stay around and shoot at the enemy

            Certainly true -- but it is very handy to be able to spray fire if you suddenly notice a couple of guys standing where you intended to land holding RPGs, and you want them dodging instead of aiming while you abort and

        • The design has inherent susceptibility to going into VRS (vortex ring state) asymetrically - ie. one rotor stops lifting. This is bad enough news in an normal single rotor helicopter but in a side-by-side rotor design it's seriously bad news (uncommanded, uncontrollable roll). Also, it seems that the V22 can go into asymmetric VRS very quickly with little or no warning to the pilot (much less warning than a normal helicopter).

          This is a fundamental design issue that isn't going to get worked out in the fie
      • I'm curious about your strong opinion because my brother-in-law worked on the Osprey project, but couldn't ever talk much about it due to the military angle...

        Because it is such a pork barrel project. As the cold war ended and the military aviation companies went belly and got merged, there is no real competition for technologies. V22 project should have been canceled after the first prototype and a new competitive bidding contract must have been awarded for new designs. V22 as the project was executed i

  • ... here's a link to another page describing Cyclogyros and how they (should) work.
    Best of all, it has pictures! ;)
  • The page linked in the summary is generating a 403 error.

    The front page of the main website seems ok.

    The page is returning an error, and this:-
    "This Website Is Powered by $0 Web Hosting"

    I guess you get what you pay for.
  • by Xoltri ( 1052470 ) on Monday October 29, 2007 @02:58PM (#21160067)
  • Apparently, Chinese and Japanese are way ahead... Working prototypes and all that... [] []

    It was always obvious that robotic overlords will NOT be speaking English as first language.

    Well... At least we can eliminate a few more of "in charge of Gundam potentials".
  • just wondering
  • the design looks like it would produce as much down presure as it would lift unless there were a way of inverting the scoop of the wing so on the down swing it could also still provide lift.
  • by goodmanj ( 234846 ) on Monday October 29, 2007 @03:21PM (#21160373)
    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.
    • What about biplanes and triplanes? This isn't much different.

      Even so, there is likely some loss of efficiency from the lower blade being in the downwash. The downwash "blows" across a much larger area than the lower wing. There is likely a velocity between maximum speed and hover, where the efficiency is best due to maximum downwash going between blades.

      Clearly, though, it is adequatley efficient, as the video shows.

      I think it's ingenious... although I can see why it's far easier to accomplish on very-sma
    • by tist ( 1086039 )
      Actually I think there are a lot more problems than just downwash. A wing or a helicopter blade produce that downwash from three components of their physical design:Camber, Thickness, and Angle of attack.
      If you want to be very efficient (at "low" speed), you should make use of all of these.
      For obvious reasons (the blade will be upside down when it is on the bottom and camber going the wrong way is not very efficient in producing lift) the blade cannot have any camber. That eliminates one part of the lif
    • It scares me you were moderated interesting.
      You need a lesson in the bernouli principal's_principle/ [] []

      Aircraft don't fly by pushing down on a bunch of air until they leave the ground.

      Forward motion (generated by thrust) is converted to lift. Lift is the result of air flow being split by the airfoil (wing). as the air travels over the top of the airfoil it must travel a greater distance than the air that flows beneath. The spre
      • by drew ( 2081 )
        I think the GP is yet another confirmation that Slashdot needs a "-1, Wrong" mod. Or perhaps a slightly more diplomatic "-1, Factually Incorrect".
      • Re: (Score:3, Insightful)

        by goodmanj ( 234846 )
        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 w
        • Re: (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 identic
        • Since you pulled rank, I will do the same, I only have a bachelors in geology, and currently working on a masters in hydrogeology. I was raised by a military instructor pilot, that also had 20+ years as a commercial airline pilot, and I grew up in the air capital of the world.

          When I was growing up and I asked what makes an airplane fly, I was started in a multi year discourse into aerodynamics.

          With discussion of bernouli, there was discussion of wingtip vortices, the purpose of wing fences seen on early m
          • Re: (Score:3, Interesting)

            by DougWebb ( 178910 )

            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 voi

            • Thats easy, Most high performance wings, those used for aerobatic and fighter planes produce close to neutral lift (these wings are close to symmetric), the amount of lift is then mostly attributed to speed and the angle of attack. by inverting the aircraft and pushing forward on the controls, the bottom of the wing will function as the top and lift will be generated.

              Low speed or heavy lift wings would be difficult to use inverted, most would only work during a maneuver such as a barrel roll where a positi
        • by sjames ( 1099 )

          The vortexes and turbulance are simply disturbances to the air that contribute to drag but do not contribute to lift (that is, they are wasted energy), as opposed to the other disturbances that are responsable for the lift. A perfect wing would produce a smooth simple downward displacement of air. Too bad it'll never happen, but we can at least move closer to that condition with research and good design.

    • 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.

      No worse than a darrieus wind turbine.

      Yes there's a downwash. It's velocity is small compared to the speed of the blade. Yes there's a change in the effective angle of attack when the blade goes through the downwash, and that affects l
  • 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!

  • It looks like it's very prone to cut things into small pieces - like people's heads.

    Too bad that the site referred to in the post seems to be slashdotted. Interesting thing is that the hosting service says: "Unlimited Web Hosting", but obviously it isn't. - But that is probably normal.

  • If by micro air vehicle they mean like the man-portable UAV's and smaller, why don't they experiment with ornithopter designs like hummingbirds and dragonflies? As I understand it, the flight mechanics for those animals really don't scale up well for larger vehicles, explaining why we don't see 747's with dragonfly wings, but so long as the vehicle is still within the same relative size as those animals, then the only problem is power supply density.

    The quad-rotor UAV designs appear to have an excellent mix
  • by Nom du Keyboard ( 633989 ) on Monday October 29, 2007 @03:46PM (#21160717)
    Let's see here:

    The design is seventy years old.
    It has never successfully flown during all that time.

    • by tmosley ( 996283 )
      And thus the flying wing was born!
    • The early prototypes didn't have anything to control pitch or resist the pitch rotation from the rotor drag when hovering.

      Like helicopters, cyclogryos need a tail rotor (pointed up/down) or fore-and-aft counter-rotating cyclogyro rotors to have six-axis control.

      Elsewhere on the board is a link to a video of a small cyclogyro with a vertical tail rotor that runs just fine.
  • There are cyclogyro like propellors used on a number of ships. The VSP [] is used most prominently these days on a couple of tugboats in Prince William Sound up in Alaska.

    The Flash animation at the bottom of the page linked as "Open iVSP - Interactive VSP Program" is truly amazing, and gives you a great intuitive understanding of how these machines work.

    Thad Beier
    • by Teun ( 17872 )
      Indeed the same principle but now in a place where weight is less of a problem.
      But I can see serious corrosion problems in this design, all these different metals rotating in a saline solution...
  • So why not use an auto gyro ala James Bond.

    Of course everybody knows the best UAVs look like spitfires. I'd sign up for a sortie or two, hope and glory blaring in the headphones, stiff upper lip, handle bar mustache, ridiculously fake old etonian accent etc etc. Although I would draw the line at the very spiffy Douglas Bader replacement legs.
  • Maybe they ought to look into a cyclogyro server cooling device in order to outmaneuver a slashdotting?
  • For whatever reason (unslashdoting perhaps) the actual link is one off from the link in the story.
    Here is [] the working link.
  • the fairy rotodyne was a much better design, and in the mid 50s had remarkable decent preformace metrics compared with today's v22. With modern technology the basic design should be able to surpass the v22. Why this wasn't done is anyones guess. My bet: a "jets are cool propellers are old attitude."
    • by Rakishi ( 759894 )
      The rotodyne and v-22 use rather similar main engines, if you consider one to be a jet engine then both are jet engines. The rotodyne however also used "actual" jet engines on the wing tips (as in rocket type engine).

      So by your own argument the rotodyne should be considered cooler.

      In other words thank you for showing your own ignorance and destroying your own argument.
  • I see paddle wheels fell into disfavor with ships around 1850 or so, having been replaced by the vastly superior propellor; why are there aeronautics engineers contemplating using them on airplanes in the 21st century?
  • For those who are interested in the ACTUAL paper instead of a nested summary here is the link to IEEE [] if you or your university has a subscription you can get the full PDF here: []
  • It'll make a really cool farm combine -- much better looking than the ugly monstrosities they have now...

Today is a good day for information-gathering. Read someone else's mail file.