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Another Look at 1930's Cyclogyro Plane Design

ScuttleMonkey posted more than 6 years ago | from the crashlo-burno dept.

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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Oblig (-1, Offtopic)

JK_the_Slacker (1175625) | more than 6 years ago | (#21159737)

I for one welcome our new spinny-wing robot overlords.

Re:Oblig (1)

muellerr1 (868578) | more than 6 years ago | (#21160149)

Cyclogyro is just his lame American name. When the character was originated in Japan in 1981 Cyclogyro's name was Gyro Robo.

Re:Oblig (0)

Anonymous Coward | more than 6 years ago | (#21160319)

I'd like to send this letter to the Prussian consulate in Siam by aeromail. Am I too late for the 4:30 autogyro?

Dwarf Fortress released (0)

Anonymous Coward | more than 6 years ago | (#21164241)

Mod this AC post up if you wish to promote the new Dwarf Fortress version [bay12games.com] , which has been a nine-month journey of daily marathon programming sessions. Congratulations to Toady One, now let's get a story on the Slashdot front page!

Like a helicopter? (2, Interesting)

MobyDisk (75490) | more than 6 years ago | (#21159803)

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.

Re:Like a helicopter? (4, Informative)

140Mandak262Jamuna (970587) | more than 6 years ago | (#21160001)

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:Like a helicopter? (2, Interesting)

ericrost (1049312) | more than 6 years ago | (#21160103)

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.

Re:Like a helicopter? (1)

140Mandak262Jamuna (970587) | more than 6 years ago | (#21160381)

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.

Re:Like a helicopter? (1)

A nonymous Coward (7548) | more than 6 years ago | (#21160883)

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.

Re:Like a helicopter? (1)

rainman_bc (735332) | more than 6 years ago | (#21161883)

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 the back why the vaccum doesn't pull it back.

Re:Like a helicopter? (2, Informative)

140Mandak262Jamuna (970587) | more than 6 years ago | (#21162757)

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.

Re:Like a helicopter? (1)

hey! (33014) | more than 6 years ago | (#21161139)

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 tissue paper wrapped around a stick of dynamite.

But in any case, it's a different issue.

Re:Like a helicopter? (1)

mangu (126918) | more than 6 years ago | (#21162987)

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:Like a helicopter? (2, Insightful)

know2much (37539) | more than 6 years ago | (#21160737)

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!!!

This is all very nice (4, Funny)

Mr.Fork (633378) | more than 6 years ago | (#21159823)

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.

Re:This is all very nice (4, Funny)

JK_the_Slacker (1175625) | more than 6 years ago | (#21159849)

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

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

Re:This is all very nice (2, Funny)

gurps_npc (621217) | more than 6 years ago | (#21160265)

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.

Re:This is all very nice (1)

PockyBum522 (1025001) | more than 6 years ago | (#21159957)

And sparklers taped to the sides.

Re:This is all very nice (0)

Anonymous Coward | more than 6 years ago | (#21160299)

But will it cut my lawn? Without supervision?
Depends on whether or not it sees your gladiolas as a threat.

Can I set it to keep the neighbours dog out?
I think a whirly-bladed laser-wielding flying robot hovering over your front yard will keep the dogs at bay. Not a problem.

Lasers? Can it have lasers? Lasers would be nice.
Naturally; but what about acoustic weapons? I want a robot that can cause intruders to literally sh*t themselves with a burst of 7hz subsonics. Messy, but hilarious.

Re:This is all very nice (1)

Doctor Faustus (127273) | more than 6 years ago | (#21160795)

But will it cut my lawn?
It would have to fly upside down to do that; be patient.

Cyclogyro (0)

Anonymous Coward | more than 6 years ago | (#21162089)

Anybody else think the name "cyclogyro" would be better used to mean a Greek bread-pouch sandwich make from one-eyed pig or sheep meat (cyclops)?

Re:This is all very nice (1)

Blakey Rat (99501) | more than 6 years ago | (#21164111)

But will it cut my lawn?

Take a look at the picture:

http://www.robotworldnews.com/100194b.jpg [robotworldnews.com]

It's almost a twin of this lawn mower:

http://www.edinformatics.com/inventions_inventors/226px-ReelMower.png [edinformatics.com]

So yes, I believe it will in fact cut your lawn.

Goldberg to the Rescue... (1)

jamstar7 (694492) | more than 6 years ago | (#21159843)

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:Goldberg to the Rescue... (2, Insightful)

Punko (784684) | more than 6 years ago | (#21159899)

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?

Re:Goldberg to the Rescue... (1)

jamstar7 (694492) | more than 6 years ago | (#21162899)

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.

Re:Goldberg to the Rescue... (3, Informative)

Rorschach1 (174480) | more than 6 years ago | (#21159955)

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.

Re:Goldberg to the Rescue... (1)

blhack (921171) | more than 6 years ago | (#21160053)

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!"

Re:Goldberg to the Rescue... (0)

Anonymous Coward | more than 6 years ago | (#21160511)

Your anus is "man-rated"

Can Cyclogyros Autorotate? (1)

StCredZero (169093) | more than 6 years ago | (#21159851)

Can Cyclogyros autorotate [wikipedia.org] 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 [google.com] but no Wikipedia [wikipedia.org]

Re:Can Cyclogyros Autorotate? (1)

LoudMusic (199347) | more than 6 years ago | (#21159915)

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.

Re:Can Cyclogyros Autorotate? (1)

StCredZero (169093) | more than 6 years ago | (#21160223)

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.

Ultralights use assisted chutes (1)

blueZ3 (744446) | more than 6 years ago | (#21160437)

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.

Ultralights only need light chutes (1)

StCredZero (169093) | more than 6 years ago | (#21160549)

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!)

Re:Ultralights only need light chutes (1)

LoudMusic (199347) | more than 6 years ago | (#21160645)

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.

Re:Ultralights only need light chutes (1)

StCredZero (169093) | more than 6 years ago | (#21162191)

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.

Re:Can Cyclogyros Autorotate? (1)

God'sDuck (837829) | more than 6 years ago | (#21161209)

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.

Re:Can Cyclogyros Autorotate? (1)

140Mandak262Jamuna (970587) | more than 6 years ago | (#21160075)

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.

Re:Can Cyclogyros Autorotate? (1)

StCredZero (169093) | more than 6 years ago | (#21160277)

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.

Reminds me of something similar (0)

Anonymous Coward | more than 6 years ago | (#21159865)

I can't remember who it was but someone was developing a new aircraft wing that had a longitudinally rotating turbine thing along the leading edge of the wing. It spun up and created airflow over the wing propelling it forward and allowing it to lift off on a very short runway. Only had a scale model I think.

Anyone know what the hell I am talking about??

Re:Reminds me of something similar (1)

Twisted64 (837490) | more than 6 years ago | (#21161551)

Which one of the Wright brothers are you? I mean, try to imagine what you're describing, but instead of a longitudinally mounted turbine, let's have a... propeller...

Re:Reminds me of something similar (0)

Anonymous Coward | more than 6 years ago | (#21161823)

Well, I found it eventually no thanks to you. It was called the Fanwing.

http://www.fanwing.com/pix.htm [fanwing.com]

http://en.wikipedia.org/wiki/Fan_wing [wikipedia.org]

see, longitudinal rotating thingy!

Re:Reminds me of something similar (1)

Riptexious (680172) | more than 6 years ago | (#21162103)

Wait a sec. I'm filing the patent now. Ok. Done. Read away.

Same fuel consumption as helicopters (2, Informative)

140Mandak262Jamuna (970587) | more than 6 years ago | (#21159869)

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.

Oh, come now! (1, Funny)

Anonymous Coward | more than 6 years ago | (#21159965)

Tell us what you *really* think about the V-22 Osprey...

Re:Same fuel consumption as helicopters (4, Funny)

pittance (78536) | more than 6 years ago | (#21160055)

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.

Re:Same fuel consumption as helicopters (1)

Chris Burke (6130) | more than 6 years ago | (#21163495)

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. :(

Re:Same fuel consumption as helicopters (1)

PetiePooo (606423) | more than 6 years ago | (#21161051)

... or the stupid plane V22, ... that boondongle from Fort Worth, V22 Osprey.

Why the animosity against the V22? [wikipedia.org] 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 [wikipedia.org] with the speed of a fixed wing has long been a dream of aviation, especially the military.

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...

Back on topic, autorotation [copters.com] in helicopters isn't an easily understood mechanism. I suspect this design would have something similar, as a combined lift+drag vector forward of the shaft-to-wing vector on part of the circuit could keep the main shaft spinning just like it does a helicopter's rotor... Granted, the glide angle is probably pretty abysmal, but it is in helicopters too. All that's needed is to get you close to the ground so you can use up the remaining rotor momentum in the flare.

There's also the possibility of stopping the rotor and gliding down as a fixed wing, but that's not as easy as others might make it sound... There would be issues maintaining lift during the transition, controlling the individual airfoils' AoA, plus you wouldn't normally have ailerons or elevators, so basic control could be difficult.

BTW, IAAHP

Re:Same fuel consumption as helicopters (1)

God'sDuck (837829) | more than 6 years ago | (#21161339)

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 speed. Many of the original requirements were shelved when they proved difficult to meet.

Cool idea....but probably going to needlessly kill a lot of soldiers while working out kinks in the field.

Re:Same fuel consumption as helicopters (2, Informative)

Rakishi (759894) | more than 6 years ago | (#21162777)

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.

Seeing as the link to TFA is dead ... (1)

fewnorms (630720) | more than 6 years ago | (#21159949)

... here's a link to another page describing Cyclogyros and how they (should) work.
Best of all, it has pictures! ;)

Re:Seeing as the link to TFA is dead ... (1)

Frosty Piss (770223) | more than 6 years ago | (#21160777)

Seeing as the link to TFA is dead ...
The link isn't really dead. They just are not accepting referals from Slashdot. Navigate there directly, and you can access it just fine.

Slashdotted? (1)

gigne (990887) | more than 6 years ago | (#21159975)

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 Doteasy.com $0 Web Hosting"

I guess you get what you pay for.

Re:Slashdotted? (1)

trogador (1170027) | more than 6 years ago | (#21160409)

I got the error,too...but you can still go to the homepage and click on the article from there, and it worked for me.

first post (-1)

Anonymous Coward | more than 6 years ago | (#21160023)

first post

Link slashdotted, so I googled around and... (1)

denzacar (181829) | more than 6 years ago | (#21160191)

Apparently, Chinese and Japanese are way ahead... Working prototypes and all that...

http://www.youtube.com/user/huyu0711 [youtube.com]

http://sciencelinks.jp/j-east/article/200523/000020052305A0951847.php [sciencelinks.jp]

Figures.
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".

How does it land? (1)

Werrismys (764601) | more than 6 years ago | (#21160203)

just wondering

Re:How does it land? (1)

whopub (1100981) | more than 6 years ago | (#21162549)

Real fast...

strange Design (1)

BlueshiftVFX (1158033) | more than 6 years ago | (#21160259)

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.

Flying through its own downwash = bad. (3, Interesting)

goodmanj (234846) | more than 6 years ago | (#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.

Re:Flying - downwash = bad. (1)

Miykayl (841085) | more than 6 years ago | (#21161489)

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-small craft.

Re:Flying through its own downwash = bad. (1)

tist (1086039) | more than 6 years ago | (#21161525)

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 lift producing capability of the blade. So we have lost some efficiency right there.
There is an analog to the "retreating blade stall" that helicopters suffer from - this is when the speed of the helicopter (a positive value) is added to the speed of the tip of the blade that is going backwards (a negative value). You can see that as the forward speed of the helicopter increases, the speed of the retreating tip goes down and that = less lift (the one on the other side goes faster, so it's busy making more lift - what a pain!) In the cyclogyro, the blade at the bottom would suffer a similar problem. Eventually (and pretty quickly) the bottom blade would not be contributing to lift at all and then will be going backwards through the free stream. A tremendous loss of efficiency although no real problem for roll stability like the helicopter.
Also as the plane moves forward the blades can no longer just point up and down as they go around the circle in the front down and back up parts of the cycle. They will have to be pointed more and more forward as the speed increases. This in turn will mean they have to be returned to a near flat position more quickly as the forward speed increases.
The design will have to have differential control of pitch of the blades in order to turn or a tail rotor. Part of the efficiency claim is no tail rotor, so the pitch will have to be varied for and aft to create more thrust on one side over the other to turn the plane and also on top and bottom of each side independently to roll the plane in order to make a "coordinated turn". (Not required, but makes flying feel a lot better).
I don't think a simple mechanical control system that can't vary the amount of pitch applied anywhere around the cycle would be very effective. At the time this design first came around, there were no sophisticated control systems that could do these things. Seems that now it would be a piece of cake.
(yes, I am a rocket scientist)
JW

Re:Flying through its own downwash = bad. (1)

protolith (619345) | more than 6 years ago | (#21161873)

It scares me you were moderated interesting.
You need a lesson in the bernouli principal

http://en.wikipedia.org/wiki/Bernoulli's_principle/ [wikipedia.org]
http://en.wikipedia.org/wiki/Air_foil/ [wikipedia.org]

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 spreading of the air as it travels over the top generates a vacuum. the air flowing beneath the airfoil tries to push up to fill the partial void. This generates lift.

Jetwash and wake turbulence are behind the aircraft.

Vortexes created by the wings (the most dangerous part of wake turbulence) are created by the air trying to go around the end of the wing to get to the top, Swept wings amplify this situation as not all of the air flows over the wing parallel to the fuselage, instead it sort of slides off toward the wingtip, a vortex propagates from the wingtip trailing behind the aircraft.

Re:Flying through its own downwash = bad. (0)

Anonymous Coward | more than 6 years ago | (#21162193)

I thought lift is created by the Coanda effect.

Re:Flying through its own downwash = bad. (1)

drew (2081) | more than 6 years ago | (#21162439)

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:Flying through its own downwash = bad. (2, Insightful)

goodmanj (234846) | more than 6 years ago | (#21162929)

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.

Re:Flying through its own downwash = bad. (2, Informative)

billybob_jcv (967047) | more than 6 years ago | (#21163945)

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 [nasa.gov]

Re:Flying through its own downwash = bad. (1)

protolith (619345) | more than 6 years ago | (#21163965)

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 mig fighters. The turbulence (minor) of jetwash and prop wash and the principals of supersonic flight.

There was never any mention of "downwash" from the air being pushed down to keep an airplane in the air.

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.

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.

To say that the air that lifts an airplane is pushing down is ignoring the concepts of pressure gradients and infinity. There is a pressure gradient, the air trying to go from high pressure to low pressure is exerting force in all directions, but it is a gas, not an orderly stack of connected molecules (press on the top one and the same force is felt on the bottom), the force is dispersed in infinite conditions.

What I am really trying to get at, is that the real action that makes a plane fly does not happen under it pushing down on the air beneath it, but it happens above the wing. An Airplane flies because it is sucked off the ground.

Re:Flying through its own downwash = bad. (0)

Anonymous Coward | more than 6 years ago | (#21164299)

I don't know where you got your degree, but even in freshman Physics they should have drilled into you the differences between force, work, and energy. If a plane starts out at 10,000 meters above the earth, and 1 second later is still at 10,000 meters above the earth, what work is being done on the plane? What work is being done by the atmosphere to hold up the plane?

Think about it. As I sit here on my chair, what force pushes against my butt? How hard is the chair pushing on the floor? Where does the energy my chair is using to simultaneously push upwards with 200 lbs. of force and downwards with 210 lbs. of force come from? I'm not saying that airplanes work like the "perfect" model in a 5th grade text book, but your model is complete hogwash.

You're modeling the plane like it was some type of rocket, requiring a constant 9.8 m/s^2 upwards acceleration to stay still. Planes don't fly by actively pushing the air around them down. That's simply not how planes work. If it were, even something as simple as a paper airplane would fly through the air exactly like a brick.

No (-1, Flamebait)

Anonymous Coward | more than 6 years ago | (#21162131)

"If one plane flies too close to another, the downwash can cause the trailing plane to crash."

Ever see the beginning of the movie, "Dr. Strangelove"? You know, the bombers refueling in mid air? One plane following below the other? Connected only by a few feet of hose? Sure didn't look to me like the trailing plane crashed...

You may wish to learn something about aerodynamics and exactly how lift is created before you mis-apply your equal-and-opposite-reaction "explanation" again...

Gyroplanes today. (0, Redundant)

gilgsn (239700) | more than 6 years ago | (#21160515)

Today, they are called gyroplanes. These simple aircrafts are still used today, and a lot of fun to fly. You can build one for probably as low as $8k. Here is a great short movie about present time gyroplanes:

http://planenews.com/modules.php?name=Video_Stream&page=watch&id=133 [planenews.com]

Gil.

Re:Gyroplanes today. (0)

Anonymous Coward | more than 6 years ago | (#21160793)

-1, failed to RTFA. This has nothing to do with gyroplanes.

Re:Gyroplanes today. (1)

gilgsn (239700) | more than 6 years ago | (#21160835)

The page didn't load.. Slashdot effect! I couldn't read it.

Cyclogyro != Gyroplane (1)

Tipa (881911) | more than 6 years ago | (#21161163)

Gyroplanes use unpowered rotors that rotate horizontally for lift. The cyclogyro of this article uses horizontally mounted, powered wings rotating vertically for lift. It's a different beast.

Nice video, though :)

Re:Gyroplanes today. (2, Informative)

querist (97166) | more than 6 years ago | (#21161173)

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.

The 4:30 Autogyro (2, Funny)

slagheap (734182) | more than 6 years ago | (#21160567)

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!

not at all new! (0)

Anonymous Coward | more than 6 years ago | (#21160611)

the Hiller Museum has a model of Irvin's Aerocycloid on display

http://www.hiller.org/ [hiller.org]

dating from 1909.

I'll bet Leonardo had something like it too :)

Interesting (1)

Z00L00K (682162) | more than 6 years ago | (#21160615)

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.

Seems overly complicated (1)

jollyreaper (513215) | more than 6 years ago | (#21160659)

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 of stability and maneuverability. Since the rotor blades are enclosed within their own hoops, there's not the same level of concern over blade strikes as one would have with a more conventional helicopter design. Energy densities in batteries are growing at a phenomenal rate, as revolutionary for these smaller vehicles as the development of the internal combustion engine was for moving beyond gliders to true powered flight. Electronics miniaturization is also proceeding at a phenomenal rate.

Would this eggbeater approach to flight be any more efficient or provide an advantage versus our current examples of fixed, rotary, and flapping wing designs?

Let's See Here... (3, Funny)

Nom du Keyboard (633989) | more than 6 years ago | (#21160717)

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!

Re:Let's See Here... (1)

tmosley (996283) | more than 6 years ago | (#21160885)

And thus the flying wing was born!

A lot like the Voight-Schneider Propellor (VSP) (1)

Thagg (9904) | more than 6 years ago | (#21160789)

There are cyclogyro like propellors used on a number of ships. The VSP [voithturbo.com] 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

Re:A lot like the Voight-Schneider Propellor (VSP) (1)

Teun (17872) | more than 6 years ago | (#21161695)

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...

What advantage? (1)

Usquebaugh (230216) | more than 6 years ago | (#21160919)

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.

Working Link (0)

Anonymous Coward | more than 6 years ago | (#21161033)

http://robotworldnews.com/100195.htm [robotworldnews.com]

Same site, linked on their main page. Looks like this might be the same article, just hosted more better++?

Consider this design for their server? (1)

ComputerPhreak (1057874) | more than 6 years ago | (#21161243)

Maybe they ought to look into a cyclogyro server cooling device in order to outmaneuver a slashdotting?

Missing Link . . . Found. (1)

nevermore94 (789194) | more than 6 years ago | (#21161249)

For whatever reason (unslashdoting perhaps) the actual link is one off from the link in the story.
Here is http://www.robotworldnews.com/100195.htm [robotworldnews.com] the working link.

rotodyne is the answer for v22 replacement... (1)

justdrew (706141) | more than 6 years ago | (#21161505)

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."

Re:rotodyne is the answer for v22 replacement... (1)

dwye (1127395) | more than 6 years ago | (#21163359)

> My bet: a "jets are cool propellers are old attitude."

But the V22 does have propellors, really big ones, too. The jet engines are there to provide power, only, like in most military helocopters. Or M-1 tanks, for that matter.

How can that be a viable design? (1)

Junior J. Junior III (192702) | more than 6 years ago | (#21162093)

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?

How did you folks think the feds malware got into (0)

Anonymous Coward | more than 6 years ago | (#21162299)

The PC is wide open and needs about a trillion lines of code just to catch malware how did you guys think the malware got into your PC anyway?

This is why i avoid IE.

all the technology in the world wont save you from (0)

Anonymous Coward | more than 6 years ago | (#21162591)

dumb leaders.

FanWing www.fanwing.com (0)

Anonymous Coward | more than 6 years ago | (#21162725)

www.fanwing.com

And another set of rotors on the tail? (0)

Anonymous Coward | more than 6 years ago | (#21162951)

It's nice to claim hovering capabilities, but what will really happen at low speeds with the tail fin? No lift anymore, so it drops and the entire contraption tilts back.

So they would need yet another rotor to keep the tail in the air? Or give up the hovering claim and settle for STOL.

flying motorcycle (0)

Anonymous Coward | more than 6 years ago | (#21163993)

i haven't seen any comments or previous slashdot articles about this - an amazing flying "motorcycle":

http://www.youtube.com/watch?v=BTNz6NftP34 [youtube.com]

don't worry i have nothing to do with these guys.

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