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Flying Robots Made From Cellophane?
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)."
Bah, I'm too late, it flew away already! :(
So today on Slashdot we've got flying robots and cars that drive themselves, but nowhere do I see the flying car that Popular Mechanics has been telling us is only five years away for the last several decades.
Soon, we will have our promised ornithoptors!
Cellophane isn't piezoelectric. It is just very amenable to carrying a lot of static charge, which is what is being employed in this case.
I am becoming gerund, destroyer of verbs.
....our new paper thin flying overlords.
As per usual; the powersource ?
Religion is what happens when nature strikes and groupthink goes wrong.
Anything that is powered by static electricity is going to be very weak.
Engineering is the art of compromise.
Could this be used for speakers? Aren't there some speakers that use a membrane instead of the normal speaker cone?
Send email from the afterlife! Write your e-will at Dead Man's Switch.
And given that they have a casting cost of 0, we'll have a ton of them.
Read: Porn
The first time I read that, I read it as "Flying Robots Made From Cell Phones". That would be seriously scary, getting attacked by a bunch of flying cell phones could ruin your whole day.
It's good to use your head, but not as a battering ram.
Wow, featherweight sub-gram flying things! I wonder if they can lift the the 23 kilo car battery needed to power it? Still, way cool.
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
Wouldn't the wingspans needed to support even a light payload with flapping wings be too large for the cellophane wing to even support it's own weight?
Gotcha
No kidding. If they're going to spy on me, at least let me pay them less to do it.
If they make them with nitrocellulose, then swarms of tiny exploding fly drones could be the new terror weapon. Don't say I didn't warn you!
One line blog. I hear that they're called Twitters now.
What does cellulose have to do with cellophane? Aren't trees and plants made of cellulose? Is cellophane modeled after cellulose? Could a plant eater eat cellophane?
Attack of the killer BigMac cartons! Directed by Ed Wood.
Bonus points if you build a Mars Lander out of AOL disks.
Table-ized A.I.
Ok. We have some gold-plated cellophane. How is that a "flying robot"? Not meaning to troll, but isn't that a bit of a leap? I understand how, possibly, that would be useful. But there are other things to a wing than just flapping. There's aerodynamics, and flapping, and such. Aren't there more efficent means of flight than cellophane wings, even if they were feasible? No, I havn't RTFA but I'd be willing to guess that nobody has actually built one of these wings.
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?
I have developed a truly marvelous proof of this comment, which this signature is too narrow to contain.
Why's it gotta be something rare and expensive, like gold? Why not old butter? I've got lots of old butter.
Care about electronic freedom? Consider donating to the EFF!
Are not piezoelectric and do not use cellophane.
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.
http://lkml.org/lkml/2005/8/20/95
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.
This would easily fail if you used it for any period of time; enviromental interference would be enough to disrupt or overcharge the current.
And on a rainy day, the robots will stay at home. Don't buy if you live in U.K!
So we're not going to have to worry about alien invasions, we're going to invent the Autons ourselves . . .
...cause quite a flap.
Cloned foods give the statement "We had that last week!" a whole new meaning.
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...
[
Just think -- it should now be possible to recycle the giant ball of candy wrappers that I've accumulated over the last thirty years...
The contest for ages has been to rescue liberty from the grasp of executive power. -- Daniel Webster
Don't worry; any time now, they'll be outsourcing the contract to spy on you to the lowest bidder. They'll make up their profit margin by cutting corners on insignificant things like accuracy.
"Ladies and gentlemen, my killbot features Lotus Notes and a machine gun. It is the finest available."
Raid may not work on such critters, but I bet this spray would: http://www.hobbylinc.com/htm/mmm/mmm77-17.htm
Good for 1002 uses...
Excuse me, but please get off my Pennisetum Clandestinum, eh!
So it should be possible to use it to build lightweight flying robots carrying cameras, microphones or sensors for surveillance missions.
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.
You don't use science to show that you're right, you use science to become right.
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 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 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.
Are these things african or european?
You know, this would have been a great April Fool's story.....
Huh?
I really wonder how many winshields will be trashed by flying gold plated cellophane insects... you know.. it's like a bullet... and if you're on the highway and hit one, they might think that it was a lost bullet... or a drive-by if there was a bunch of them :P
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...
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.
I went to the city because I wished to live without deliberation.
Surely the bumblebee could be using this concept to fly then?
Also perhaps could tap into radio, microwaves and solarwinds to fly using this method?
When shit hits the fan get some of these https://youtu.be/pY-GncsZ-UE
Really small hamsters. Of course, designing the wheel that small might be a problem.
It's a simple question of weight ratios! A five ounce bird could not carry a one pound coconut.
The pain was excruciating and the scarring is likely permanent, but that just means it's working.
>An airplane wing does not produce lift because it is angled downwards,
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f t_and_drift.htm
>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.
--Brandon / Split Infinity Music
Oh, great. So now, when Skynet launches its attack on the human race and needs raw materials to build additional attackbots, all its androids have to do is to raid the nearest hardware, grocery, or stationery store for some Scotch® Tape? Curse you, Inha and Texas A&M Universities! You have betrayed the human race!
So how do planes fly upside down then?
"Cats like plain crisps"
I just had a terrible vision of a new Hitchcock movie based on those flying cellphones--a remake of The Birds as The Telemarketers.
:-]
Reach out and touch someone?
I'm not complaining - seriously. I don't really give a damn about karma. Not understanding something bugs the hell out me though, and this leaves me baffled.
Lost: Sig, white with black letters. No collar. Reward if found!
By having the correct angle of attack regardless of camber, READ what he wrote... Jeeez!
McGyver strikes again.
Is there nothing he can't do?
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 force is going to be dissipated as friction in bending the material.
Bottom line is, this material isnt a particularly good for this application.
Nobody seems to have picked up on the fact that this means we will may be able to get things like large lightweight, cheap mems arrays of mirrors powered by a watch battery. I'm looking forward to real nice looking ebooks, tiny passive image projectors, and maybe some inexpensive holography. This stuff sounds great! Only problem is now we definitely will have a spypest(TM) problem, though mostly only in dry climates I imagine (rain will absorb all the microwaves I hope).
as the first manual voltage switcher on the first high altitude trial of an aircraft which flaps its wings using this technique. Good if we could get pictures too, especially when the inevitable occurs.
How many beans make five, anyhow ?
Since trees are made of cellulose, does that mean the branches waving in the breeze are generating electricity and could it be harnessed?
In the US, Cellophane tape is not common anymore. Plastic tape is more common.
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.
http://lkml.org/lkml/2005/8/20/95