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Single Propeller in the Air

drone that is a single propeller flying in the air
 
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The is a single propeller flying by itself in the air, via radio control. The speed and angle of the propeller is varied to keep it in position, by eye if you are really good, or by software for those who need help.
JesusHChrist, Jan 17 2017

baked https://www.youtube...watch?v=h_zWvfvY2GU
[Voice, Jan 17 2017]

Same as above http://mashable.com...drone/#SjY2o9QmL8q2
[Voice, Jan 17 2017]

Newton's laws of motion https://en.wikipedi...on's_laws_of_motion
[hippo, Jan 18 2017]

[link]






       What will it push against to turn? I think at minimum you need 2.   

       Or is this one of those propellers on sticks you by in the souvenir shop and spin between your hands and it launches itself away, and then comes down fast stick first into the stroller of another family of tourists?
bungston, Jan 17 2017
  

       //The is a single propeller flying by itself in the air// No, it would be a single propeller, attached to a frantically spinning motor and battery pack, falling by itself in the air.   

       I have seldom met someone with such a profoundly deep depth of misunderstanding as to how things work.
MaxwellBuchanan, Jan 17 2017
  

       //No, it would be a single propeller, attached to a frantically spinning motor and battery pack, falling by itself in the air.//   

       But if you take the sycamore seed as the prototype its entirely doable. The battery could be the seed bit.   

       What is more worrying is that this is the 4th exact same idea posted by [JHC]. In Doctor Who terms, he's data ghosting.
bigsleep, Jan 17 2017
  

       Wouldn't that be //I have seldom met (Researchers at the Institute for Dynamic Systems and Control at ETH Zurich who have created a new kind of flying machine that only needs one blade to fly) with such a profoundly deep depth of misunderstanding as to how things work//.
JesusHChrist, Jan 17 2017
  

       //But if you take the sycamore seed as the prototype its entirely doable.//   

       No, it entirely isn't. A sycamore seed falls, and doing so causes it to rotate (as a whole). If you stick a motor on a sycamore seed, it will end badly. Just stop and think about the forces and reactions involved.   

       OK, now stop and think a bit more.   

       At minimum, you need a big, draggy surface to oppose the counter-rotation. Realistically, you need two propellors counter-rotating.   

       Or look at [Voice's] link. Even with a relatively massive and elongated body to reduce spin, the whole body of the drone spins in the opposite direction. This is one of the reasons conventional helicopters have tail rotors or tail thrusters.   

       As for [JHC], I think he's unplugged and these ideas are just the result of charge draining from his capacitors.
MaxwellBuchanan, Jan 17 2017
  

       I keep posting the idea again and again because the annotations make it clear that no one has understood it. This idea isn't any different from a feather floating in the air or a sphericon floating in the air, its the same thing and its already being done somewhere in the world where people are getting paid to do it, while I am sitting here behind my fucking computer trying to figure out where your psychotherapy went wrong.
JesusHChrist, Jan 17 2017
  

       //its already being done somewhere in the world where people are getting paid to do it//   

       Well, that's OK then - it should be straightforward to link a video. Who? Where? Why? When? How?   

       By reposting the same stupid idea you are, inadvertently, making it not fully impossible to confuse you with a complete twat.
MaxwellBuchanan, Jan 17 2017
  

       Rockets mounted on the tips
pocmloc, Jan 17 2017
  

       I think I understand what [JHC] has been trying to describe.   

       Imagine a large feather. Put a weight on the stem, all the way at the end, the same weight as the feather. Replace the weight with a motor of the same weight, hinged against the feather. Now if you use the motor you should get some torque against the feather. The same way a bird's muscles pull against its wing, if the bird only had one wing. you see now it has started to push against the air in one direction, with a force proportional to its weight.   

       Now before the motor is running at full speed and has run out of torque to provide, reverse the rotation direction. The feather will be pulled opposite to the engine's pull as the engine spins.   

       For an analogy stand on frictionless roller skates holding a large piece of cardboard. Move the cardboard as quickly as you can from one direction to the other. Your weight will move the cardboard a bit as you start spinning in each direction.   

       Now curl the cardboard a bit. If you were doing this on an asteroid in full air density you could possibly generate enough lift to move off the ground.   

       The laws of physics remain intact. You are, in effect, jumping between the air molecules on the left and on the right.
Voice, Jan 17 2017
  

       //Now curl the cardboard a bit//   

       That's a bit of red herring, basically you hold the cardboard at an angle, ideally at 90 degrees to the axis of rotation as if waving a stiff flag up and down. The trick to controlling altitude and direction is to modulate the flap speed as required. This is easier to envisage with the single propeller video (2nd link), than imagining a single blade with counterbalance but they are functionally equivalent. Precession is easily accommodated by air resistance, the fastest wing moves being used to correct precession.
bigsleep, Jan 17 2017
  

       Another way to describe it is a gigantic gaping opportunity where little kids all over the world will be discovering things in the field of flapping flight by just sticking random things onto and taking things off of a simple radio controlled motor/software setup with removable propeller. Little kids all over the world inventing shit by throwing random foam shapes onto a propeller and I am sitting here where I have been for the last 15 years behind my computer listening to your crap and trying to pick my self esteem off the floor.
JesusHChrist, Jan 17 2017
  

       //Now before the motor is running at full speed and has run out of torque to provide, reverse the rotation direction. // So, flapping.   

       //I am sitting here where I have been for the last 15 years behind my computer listening to your crap and trying to pick my self esteem off the floor.//   

       Well, there's your problem, [JHC]. If you had actually got off your butt and done whatever it is that these //little kids// are supposedly going to do with your gift to mankind, you might have (a) a little self esteem and (b) something to show for it and (c) even a video to post to prove us all wrong.   

       Personally, I'm an expert on breeding world-class racehorses. I've never actually done it, but I know how it's done.
MaxwellBuchanan, Jan 17 2017
  

       Max, I think you've just been schooled by a lucky video find. Humility is not your best trait at the moment, but improvement is always possible.
RayfordSteele, Jan 17 2017
  

       //Max, I think you've just been schooled by a lucky video find.//   

       With respect [RS] I posted the same response about single blade control prior to the videos on a previous idea. If we all give up and say knowledge is always a 3rd party thing then sure, lets bow to whatever fake news we get fed. My first source is usually my own brain with Google a corroboratory source.   

       I would give most [HB]'ers the same credit. Sheesh, you'll be talking about feelings next.
bigsleep, Jan 17 2017
  

       // you'll be talking about feelings next //   

       EEEEeeeewwwwww ...
8th of 7, Jan 17 2017
  

       //a lucky video find//   

       I mentioned the video, in an anno about 2 screenfuls up from here. The single-prop drone is flying because it has, and I quote none other than myself here: //a big, draggy surface to oppose the counter-rotation//. In other words, it is exactly what I said.   

       If, when [JHC] says //a single propeller flying by itself in the air//, he actually means "a single propeller strapped to a big draggy thing", then I beg his pardon and reprimand myself for failing to divine his meaning. Or if by "propeller" he means "flapping wing" (or, for all I know "helium balloon"), then ditto.   

       If you have what [JHC] describes, namely //a single propeller flying by itself in the air//, then whatever is driving it will just wang itself around in the opposite direction. Unless the body of the machine has sufficient drag, the wanging will really, truly happen. Wang wang wang.   

       You can even predict *how much* wanging will happen. If the body (which, presumably, is at least an electric motor) has little effective rotational drag, then the body will wang around very fast indeed, and the prop will do very little useful work. If the body has the same rotational drag as the propeller, then the body and the propeller will rotate at equal and opposite speeds. If the body has a lot of rotational drag, then the propeller will rotate quickly and the body will counter-rotate slowly.   

       But however you look at it, a //single propeller flying by itself// just won't. It's like trying to make lightweight scissors by removing one blade and handle.   

       //Humility is not your best trait at the moment// nor, indeed, ever. I never signed up to humility. And I have more than a reasonable share of irritability, irascibility, and many other things beginning with ir- when it comes to homeopathists, tantric plumbers, astrologers, and people who keep posting the same dumb yet simple idea without even bothering to try to prove to themselves whether it will work or not. Actually the tantric plumbers are the worst.   

       One of the joys of the HB is that people can pull apart ideas using whatever degree of rationality is available to them. If I kept insisting that an inflatable gun was the future of military hardware, I wouldn't expect [8th] to give and say "Well, OK" just because I posted it six times.
MaxwellBuchanan, Jan 17 2017
  

       FIne, it's a great idea. I'm sure I'll be hopping on a sphericon or a feather next time I head for Washington. I'll even give it a [+]. I'm out of merit badges at the moment.   

       //Sure, double down on your own blog with bullshit. But don't do a Trump or a CIA on us. We really don't need more fake news. // Sadly I have no blog. But which fake news were you referring to?
MaxwellBuchanan, Jan 17 2017
  

       // Discuss //   

       A discuss is much more like a Frisbee™ than a precessing feather, shirley ?
8th of 7, Jan 17 2017
  

       Heya, [8th], I've got this great idea for a lightweight inflatable gun.
MaxwellBuchanan, Jan 17 2017
  

       //MB] Please do not do this on the HB. Sure, double down on your own blog with bullshit. But don't do a Trump or a CIA on us. We really don't need more fake news//   

       Wait, what? What the fuck just happened? [MB] is, for what I can tell, absolutely correct, given the (vague) information made available about this "idea". If, however, [JHC]'s idea consists of a lot more features, and works in a way that simply hasn't been explained properly on this page or any of the other clones, then fine. But [MB] is not at fault.   

       It could be there's an idea in here somewhere - we just don't have enough information to know that. I could post an idea with the words : "Use strong force to cook breakfast" - but I'm not adequately describing a nuclear powerstation, distribution grid and inductive stove top, am I? Is it up to the reader to fill the gaps, especially when the concept is obviously very abstract?
Custardguts, Jan 17 2017
  

       When it gets to the point where I'm absolutely correct, we're in it pretty deep.
MaxwellBuchanan, Jan 17 2017
  

       Interesting link. I know it would mean another actuator but I think that a single flywheel spinning opposed to the propeller and offset from center would stabilize their single prop design.   

       Not if it's spinning in the same plane as the propeller - flywheels don't resist translation. If it's spinning with its axis horizontal then it might.
MaxwellBuchanan, Jan 17 2017
  

       How about a Catherine wheel with a slight propelloid twist?   

       Just refuel the thing occasionally just as if it had jet engines, or if you are feeling UFOish, ion engines(!) far from earth.   

       ... a flying propeller   

       ...t would work at least as well as [Bungston]s wood stick spinners.
beanangel, Jan 17 2017
  

       // Not if it's spinning in the same plane as the propeller - flywheels don't resist translation. If it's spinning with its axis horizontal then it might. //   

       hmm, are you s... scratch that.
This has not been my observation.
Torque on a spinning body induces precession at ninety degrees to the force acting on it. It may work better with a horizontal axis, but it will counter a propellers spin given either orientation depending on distance from center.
  

       ...oh yeah, and it needs to be spun up to speed while level before take off so that gravity acts on the lever.   

       As much as jhc's litter fouls up the place and I missed the other four postings, I expect as much from his offerings. it is ever so much more enjoyable when the arrogant take one on the chin every so often. Expect such a reaction from time to time.
RayfordSteele, Jan 17 2017
  

       Starts taking bets on m'lord Buchanan vs JHC duel.
not_morrison_rm, Jan 17 2017
  

       There's no duel. JHC is trying to express his frustration and MB is trying to deter trolls from reasoned discussion.   

       Both are excelling at their chosen tasks but are failing to hit the target.   

       ...   

       Participation pins all around!   

       Please, won't someone consider tip-mounted rockets?
pocmloc, Jan 18 2017
  

       [pocmloc] That must be what JHC was thinking of!
hippo, Jan 18 2017
  

       //This is easier to envisage with the single propeller video (2nd link), than imagining a single blade with counterbalance but they are functionally equivalent//   

       No, they're not. The drone relies on air resistance against the direction of the main rotor to allow it to keep moving in one direction. The cardboard does not need opposing air resistance at any one point. It's horribly inefficient but given a sufficiently light and strong motor it could fly without a force immediately opposing its path through the air. It borrows against its momentum with each flap of the wing.
Voice, Jan 18 2017
  

       [pocmloc], tip rockets/tipjets are a thing, normally for dodgy helicopters. In fact, you only need 1 tipjet, and your big prop blade out the other side (look up "monocopters"; working, controllable RC versions exist).
But tipjets are not what [JesusHChrist] is talking about; he's expecting a motor to flap a feather/propellor without it being attached to anything else.
neutrinos_shadow, Jan 18 2017
  

       // Please, won't someone consider tip-mounted rockets? //   

       <deploys substantial proportion of Borg Collective computational resource to consider tip-mounted rockets >   

       What a truly excellent idea, virtually flawless. Compact, economical, powerful, simple and reliable. Clearly the optimal solution to the problem*, given the problem of subjecting minaturized gas-turbine engines to severe side-loading because of g-forces arising from high speed rotation.   

       *whatever that might be.
8th of 7, Jan 18 2017
  

       //The drone relies on air resistance against the direction of the main rotor to allow it to keep moving in one direction.//   

       In simplistic terms yes, but it demonstrates well the controlability of a single propeller. I was mostly thinking of the single blade version. Which goes like this -   

       Take one large featherish blade (with the feather stripped from one side so the quill is exposed along one side for its length) and insert quill end into a motorised ball also containing the battery pack. It should look like a sycamore seed and when dropped it should behave like a sycamore seed and auto-rotate to get it to fall slowly.   

       Now imagine the ball in a frictionless support so that it can spin freely, with the feather sticking out horizontally and flat. The motor in the ball attempts to rotate the feather around the axis of the quill, but moving in a frictionless socket, it mostly just spins itself - the air resistance on the feather resists its rotation. However, to increase the angular momentum of the ball and battery pack, it must exert a rotation force on the feather and it does turn. When the feather reaches e.g. 45 degrees from the horizontal, the ball spins the opposite way and the feather turns downward. This twisting motion around the length of the quill causes a flapping effect when repeated.   

       The flapping motion should cause the system to rotate in the horizontal plane around a point (once liberated from the frictionless support) not far from where the ball and quill meet.   

       When the speed is ramped up, the thing should take-off, well almost. We have one problem to solve first - when supporting its own weight one direction of rotating the feather will be a bit harder (assuming the rotation itself is providing a lot of the lift). This can corrected by altering the rates of rotation for up and down parts of the flap - air resistance is non-linear with speed so a rapid up flap and slow down flap could correct any rotational inertia mismatches over the cycle.   

       Flight control is done similar to the single propeller video - more thrust equals up and timing up thrusts with rotational position can create a tilt so that thrust gives movement in the horizontal plane.   

       [edit: It could well be that if the ball contained a giro spinning in the horizontal plane, then the design wouldn't have to rely on inertial momentum to generate wing forces. The giro could smooth out the up and down twist of the feather at the cost of less maneuverability.]
bigsleep, Jan 18 2017
  

       //monocopters// very good, thank you.
pocmloc, Jan 19 2017
  
      
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