Flying Robots Made From Cellophane? 148
Roland Piquepaille writes "Researchers have discovered that ordinary cellulose is a piezoelectric and smart material that can flap when exposed to an electric field. ScienceNOW reports that electricity can give life to cellophane. When you put a very thin layer of gold on each side of cellophane, and that you apply electric current to the gold layers, one positive, one negative, the cellophane curved toward the positive side. If you switch the voltage fast enough, the cellophane starts to act as a wing. So it should be possible to use it to build lightweight flying robots carrying cameras, microphones or sensors for surveillance missions. Read more for additional references and pictures about this electroactive paper (EAPap)."
Nothing for you to see here. Please move along. (Score:3, Funny)
Comment removed (Score:5, Interesting)
Re:I'm angry (Score:2)
Re:I'm angry (Score:5, Insightful)
nowhere do I see the flying car that Popular Mechanics has been telling us is only five years away for the last several decades
It's called a "helicopter". You can buy one, or you can rent one for temporary use. If you get seriously injured, a flying car will come and take you to the nearest hospital. Hopefully you have insurance; they're expensive to operate.
Re:I'm angry (Score:3, Informative)
http://www.moller.com/skycar/
Dune (Score:2)
Artifact Creature (Score:5, Funny)
Re:Artifact Creature (Score:1)
Re:Artifact Creature (Score:1)
Re:Dune (Score:1, Interesting)
http://www.ornithopter.org/ [ornithopter.org]
Re:Dune (Score:1)
I understand the basic idea of the aerofoil. But are you overstating it? If an angled wing doesn't generate much lift, how is it that stunt pilots can fly upside-down? I thought in this case the wing angle has to overcome the downward aerofoil "lift".
Or what about all those toy rubber-band powered planes with flat wings?
Re:Dune (Score:2)
In one of the sailplanes I've flown, the elevator is a flat board with a hinge, and down near stall speed you can feel it buffet, but the primary fact is that any lift from the tail is generated purely by the angle of attack of the surface hitting the air. (Schwiezer 1-26 btw)
Actually... (Score:5, Informative)
>it generates lift almost purely because of its shape.
Actually, you are quite mistaken.
I am an aerospace engineer. I have a BS in Aerospace Engineering and 16 years experience conducting flight test on a dozen aircraft ranging from Cessna- to 707-sized. I have also published papers on the process.
A wing produces lift according to this basic equation:
Lift = 0.5 * Coefficient of Lift * Density of the Air * Wing Area * Airspeed squared
This includes a few approximations since I can't type various symbols in plain test. You can look at the properly written equation here: http://www.aerospaceweb.org/question/aerodynamics
Coefficient of lift, part of that equation, is itself a direct function of Angle of Attack - the angle at which the chord of the wing meets the air. ("Chord" is defined, roughly, as a line between the front and back edges of the wing.)
The wing curvature, or camber as you correctly call it, is a contributor, but far from the only one, to the equation of lift coefficient versus angle of attack. A flat, or non-cambered, wing will produce zero lift at zero angle of attack. Increase the camber, up to a point, and you increase the lift at zero angle of attack. Or you can increase the angle of attack at zero camber to increase the lift. For that matter, you can spin a cylinder in an airflow and generate lift - zero camber, zero angle of attack (it's a circular cross section, so there's no angle!). So there are MANY factors influencing lift - any combination of these is possible; you just need to select which ones are most beneficial to a given design requirement.
As a matter of fact, the first documented equation to describe lift included only angle of attack and speed. It wasn't until decades later that careful observation of bird wing structure revealed the importance of camber. There's an intriguing story here about the Wright brothers and their development of the theory of lifting bodies, and how they overturned decades of established wisdom: http://www.first-to-fly.com/Adventure/Workshop/li
In a very simple and small wing (like most insects, which obviously can fly), it's almost ALL angle of attack, and no camber. Consider a dragonfly. The wings are perfectly flat. And the creature must create not only lift but also forward thrust with those wings. Quick and repetitive motions (as mentioned in this article) are perfect for this requirement. Camber has nothing to do with it, and camber, in fact, would impede the dragonfly, because the wing must also be capable of generating lift while moving backwards - and any effective camber is usually detrimental while going backwards. Finally, in the case of insects, the qualities of air are different at small scales (the so-called Reynolds Number effects) and lift operates somewhat differently from in large airplanes.
Consider also a dime-store balsa wood glider. In its cheapest form, the wing is completely flat. Yet it flies just fine. Or consider the paper airplane. It flies just fine with a slab of paper for a wing.
In short, you can take this article at face value regarding simple wings and lift. There are other wishful comments, but the aerodynamic description is quite fine.
Re:Actually... (Score:1, Funny)
So I guess you think that makes you some kind of authority on the subject?
er - really? (Score:1)
Re:er - really? YES, Really! (Score:1, Insightful)
Re:Dune (Score:1)
Re:Dune (Score:2)
Re:Dune (Score:2)
Yes, I did see the movie, and yes, I know that's where the sonic tank came from. That was more of a goofy question, than something I actually expected an answer to. :)
FWIW, the "for some reason" that the sonic weapons were included in the m
Not Piezoelectric (Score:5, Informative)
Very thin on fact (Score:2)
Anything that is powered by static electricity is going to be very weak.
Re:Very thin on fact (Score:2, Insightful)
Hmm, think I'll grab a metal umbrella and go stand outside in this lightning storm to test that out.
Don't wait up, I'll be back in a flash...
Re:Not Piezoelectric (Score:5, Insightful)
Some "sheet transducers" used in ultrasonics (and the really expensive "plastic sheet" speakers) sound an awful lot like this "recent" advance. I'm starting to wonder how new this result really is.
the really expensive "plastic sheet" speakers (Score:5, Informative)
They work by putting an electrostatic charge on a mylar sheet, which is close to what the GP poster said.
And what you call cellophane wrap is not made of cellophane (or cellulose). It's regular petrochemical plastic based.
Cellophane (both wrap and tape) hasn't been in households for a long time now, at least 30 years.
Re:the really expensive "plastic sheet" speakers (Score:2)
that's interesting to know. (Score:2)
But my comments about the other stuff still stand. The clingy wrap people often call cellophane isn't cellulose-drived. Cellophane isn't clingy, in fact it is rather crinkly. When it was used as a kitchen wrap, you had to tape or rubber band it onto bowls.
Candy wrappers are sometimes still cellophane. Think of the crinkliness of the wrappings on hard candy and how non-clingy they are.
Re:Not Piezoelectric (Score:2, Funny)
Re:Not Piezoelectric (Score:2)
I for one welcome... (Score:3, Funny)
Re:I for one welcome... (Score:4, Funny)
When I first read the title, I thought it said "Flying Robots Made From Cellphone".
At least they would still be paper-thin...
Re:I for one welcome... (Score:1)
Re:I for one welcome... (Score:3, Funny)
One comment (Score:5, Insightful)
Re:One comment (Score:2)
Re:One comment (Score:2)
Re:One comment (Score:2)
Microwave power transmission /. nerds read the actual paper [acs.org] (PDF) and tell us more about what's going on. It goes into much depth and will undoubtedly scratch your itch for information.
I suggest all the turbo
Re:One comment (Score:1)
Re: Power source? (Score:1)
Speakers? (Score:5, Interesting)
Re:Speakers? (Score:3, Informative)
Surveillance missions uh (Score:2, Funny)
Read: Porn
Re:Surveillance missions uh (Score:1)
Need to get my eyes checked. (Score:5, Funny)
Re:Need to get my eyes checked. (Score:1)
Re:Need to get my eyes checked. (Score:2)
Re:Need to get my eyes checked. (Score:2)
Re:Need to get my eyes checked. (Score:4, Funny)
Especially if they were all ringing with incoming calls from telemarketers.
Re:Need to get my eyes checked. (Score:1)
A New Hitchcock? (Score:2)
Reach out and touch someone?
Re:Need to get my eyes checked. (Score:1)
Cool! (Score:4, Funny)
I am going to wait for the one that can carry the HD camera though, is it worth investing in SD parts at this point in time?
-Charlie
Re:Cool! (Score:3, Funny)
Supposing two of them carry it together?
Re:Cool! (Score:3, Funny)
What, held under the dorsal guiding feathers?
Re:Cool! (Score:1)
African or American?
Wingspans.. (Score:3, Interesting)
Re:Wingspans.. (Score:5, Interesting)
Thats correct, though people may develop lightweight payloads as well. Here in Melbourne a bunch of peoople used to (and perhaps still do) fly model airplanes in the domed reading room of the state library. This is a really big room with still air. The planes are made of small amounts of balsa and a sheet made by dripping a plastic compound onto the surface of bath of water. They were powered by a rubber band.
One of these planes would fly slowly to the roof over about five minutes and glide slowly to the floor. They flew at (I suppose 10 or 20 cm/s). One day I witnessed a disaster when the airconditioning got turned on by accident and the entire fleet got caught in a scale hurricane.
Re:Wingspans.. (Score:1)
No? Then it never happened.
Is it an African swallow or a European swallow? (Score:2)
SWAT... (Score:2, Funny)
Re:SWAT... (Score:2)
"OMG! Spy-cams!"
"Call in the SWAT-team!"
Watch out for suicide fly bombers! (Score:2, Interesting)
Re:Watch out for suicide fly bombers! (Score:1)
explain (Score:2, Insightful)
Re:explain (Score:1)
Re:explain (Score:2)
Re:explain (Score:1)
Re:explain (Score:1)
I for one... (Score:1)
Dial M for hunger (Score:1)
Bonus points if you build a Mars Lander out of AOL disks.
How is this realistic? (Score:3, Insightful)
What is the reason for one of these things? Are they more energy efficent?
The only thing I can think that these would actually hold up (if they could do anything) would be something smaller than a bumblebee. What can a fly-sized robot do? And, in 50 years when we have useful ones, won't we have another means of flight?
Re:How is this realistic? (Score:2)
Gold? (Score:3, Funny)
positive? (Score:2, Insightful)
Soooo...we can create positive currents now? *sigh* There are so many errors in grammar here, in addition to the errors in theory. Could we get some editors that actually know the language a little better? Day after day of insanely bad summaries.
Re:positive? (Score:2)
Re:positive? (Score:1)
Re:positive? (Score:2)
Yep, positive current. We generate some positrons and feed them into a a matter-antimatter reaction chamber. That's what is actually needed to power these, uh, tiny things. We didn't think it could be done until Geordi inverted the warp field and hooked up a mini-deflector dish to each of the flying cellophane wrapp... ah, 'robots'.
Now all we need to do is make these things able to carry a payload of some decription without collapsing under the strain... They should do someday in some form, but this early
But.... (Score:1)
Did enyone else read that as (Score:1, Redundant)
I'd thought the phones were taking over. I need to buy a new one now.
Rainy day... (Score:1)
Great (Score:1)
This will no-doubt... (Score:4, Funny)
Mr. Wizard of the 21st Century (Score:3, Funny)
Hey, kids, let's do a little experiment together, shall we? Don't forget your shop glasses. Let's get started.
You're going to need a few household items.
Have your mom or dad, or favorite grad student uncle, to assist you in using the equipment to achieve an even mono-molecular deposition of gold onto your cellophane tape...
Wow!! (Score:2)
dammit i dugg and now what (Score:1, Troll)
Re:dammit i dugg and now what (Score:1)
From looking at your recent deluge of Digg promoting posts it would appear either someone has been using your ID without your permission, or you're a prevaricating masochist.
Proof of concept interesting, but... (Score:2)
Right... and this is going to do so much better than my lightweight AirHogs remote control plane when the wind is over 5mph. (not) In still air, sure. But how much of that can you count on to be able to depend upon such a craft for surveillance purposes? It's way too much of a maybe.
Does Roland get a kickback from ZDnet? (Score:5, Insightful)
It's Roland the Plogger again, writing about something called EA-Pap. That's so Roland.
Piezoelectric films are not new. PVDF films like Kynar [welchfluorocarbon.com] are peizoelectric, and they've been used for hydrophones, speakers, and pressure sensors for years.
Actually, the big recent advance in pizeoelectric actuators is subminiature rotary motors like this Squiggle [newscaletech.com] device. Now, very tiny motors can be made for applications like camera lens autofocus. The initial application looks to be cramming autofocus machinery into cell phone cameras.
Laden flight velocity? (Score:2, Funny)
OMG Flying Cellphone Ponies!!! (Score:2)
millions of them? (Score:1)
We all know that there will be a lot of them that will be trashed because they got in a gust of wind and got crashed in a wall, hit by a car... or mistaken as an insect and pummeled to death by a scared lady...
Re:millions of them? (Score:1)
Well, it would explain how Kennedy and Connally were shot seven times with only one projectile. This must be old tech already ! *paranoia*
Bumblebee uses cellulose in wings structure... (Score:1)
Also perhaps could tap into radio, microwaves and solarwinds to fly using this method?
And I, for one, welcome our celluloid overlords (Score:2)
A flying robot made out of cellophane. (Score:1)
Is there nothing he can't do?
Really off base story! (Score:2)
If you're going to power an airplane, you need a Reliable, High-efficiency energy to motion converter. You can't just choose any old motor, especially a totally unproven one. Piezoelectric transducers are not very high efficiency. Then there's cellophane, which is NOT particularly piezoelectric. Even if it was, piezo transducers need hundreds to thousands of volts to really flap-- not something that's readily made from low voltage batteries. And you have the problem that a lot of the bending
Awesome display devices coming (Score:2)
Re:Wonderful (Score:2, Funny)
Re:Wonderful (Score:3, Insightful)
Re:Wonderful (Score:1)
Good for 1002 uses...
Re:Wonderful (Score:2)
This is one of the most pro-privacy forums I'm aware of. Every time some new revelation is made about NSA spying on us, a whole new raft of comments follows decrying the loss of civil liberties and personal privacy rights. Those comments are consistently modded up - so why was the quoted comment modded into trollsville for saying the same thing? Redundant I could understand - it's not very original. But troll?
I'm not c