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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)."
As per usual; the powersource ?
Religion is what happens when nature strikes and groupthink goes wrong.
Not so sure about that. According to the article, *cellulose* IS piezoelectric, which may or may not be due to some small-scale movement of otherwise static charge. Cellophane is made from processed cellulose (I'm not sure of the details). I agree that cellophane is amenable to carrying static charge (thus the success -- and frustration -- of cellophane wrap). On the other hand, piezoelectricity is also caused by interactions of (mostly) static charges, usually in certain symmetry classes of crystals.
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.
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.
it's a blue bright blue Saturday hey hey
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.