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Access control curtain   (+11)  [vote for, against]
Bead curtain becomes stiff on command

It looks like an ordinary bead curtain, but with rigid rods in between bead shaped joints. The joints are filled with a fluid which solidifies in an electric field (electro-rheo-something). The curtain also incorporates conductors connecting each joint.

Maybe couple it with a video camera and PC running face recognition software ...
-- neelandan, Dec 11 2001

and why? practical joke in the curry restaurant?
-- lewisgirl, Dec 11 2001


Would this be strong enough to be rigid over a 6-foot length? It might be better just to lock the bottom of the curtain to the floor. Or buy a door.
-- pottedstu, Dec 11 2001


I see this idea more as "Prosthetic Bead Curtain" where each strand of beads is individually addressable and can be made to reach out and grab hold of things like an octopus's tentacle or just squirm, creepily.
-- hippo, Dec 11 2001


Do away with the electro-rheo-thingy, and just have hollow lines making up your curtain so that you can drop thin metal rods down to rigidify them.
-- pottedstu, Dec 11 2001


You don't even need thin metal rods. If the beads are so shaped that they fit together almost in the manner of vertebrae, then by tensioning a flexible cord threaded through them they form a rigid structure.
-- angel, Dec 11 2001


"Is that a new bead curtain you've got?"
"No, actually they're lengths of tubing filled with custard. Look what happens when I pressurize them - Ooh, sorry - do you want me to rinse out your trousers? Mind youself here - it's slippery"
-- hippo, Dec 11 2001


Get all the bugs worked out, and include that face recognition bit, and you can really tease prisoners. Make their cages out of the bead stuff, and it remains flexible until they approach. Guards walk right through, but the prisoners can't. Kind of like that Greek myth about the hell torture of not being able to drink the water you're standing in, etc. (pardon me for not having a better memory).
-- quarterbaker, Dec 11 2001


[quarterbaker]Imagine the guard's suprise when the inmate approaches while the guard is walking through the beads, causing massive injury to the guard as the beads rigidify.
-- JakePatterson, Dec 11 2001


I like this idea. Sort of a force field without the WIBNI aspect. If nothing else, it might be useful for containing pets and small children.
-- phoenix, Dec 11 2001


Threat of extreme physical violence?
-- angel, Dec 12 2001


I think solutions involving passing threads/string/cords through the beads and tightening them wouldn't be very effective, owing to the natural elasticity of the string. They might be more rigid, but they'd still be able to bend somewhat.
-- pottedstu, Dec 12 2001


[P Oak]: I remember those toys too. That's what I meant earlier when I mentioned vertebrae.
-- angel, Dec 12 2001


This was suggested by the many people including a "force field" as part of their ideas.

potts & lg: As it stands, it does not have a practical application except possibly as a practical joke.

Make the curtain two dimensional, with warp and weft lines & controlled joints - maybe that will do for a new idea, electrostatically hardening cloth.
-- neelandan, Dec 12 2001


The joints could be addressed in the same way as the old magnetic core memory devices.
-- angel, Dec 12 2001


Not if the rigid length extended into a socket-like affair recessed into the door lintel.
-- angel, Dec 12 2001


Possibly the bottom of the bead string could be magnetically drawn to a small clamp in the floor, which would grab it and prevent people from pushing the beads aside until it was released.
-- wiml, Dec 12 2001


Waugsqueke mentioned making the curtain hollow and pressurising with custard in order to make it stiff. Hippo is responding to that (deleted) annotation.

Pertinent Oak said something about toys which had articulated limbs tensioned by strings.

Electrorheological fluids (ERFs)
Scientific American September 1988 page 30:
"When several thousand volts are put across a cell containing this type of mixture, the suspension can become as solid as Jell-O within a fraction of a second."

Several thousand volts! Phew!! "Starch and transformer oil" Yuck! Sorry guys, that electrostatically hardening cloth idea is off. It would have been cool, to have a jacket you put on, which hardened into body armour, before mounting that 135 mpg bike to roar down the middle of the road, forcing ancient trucks with no crumple zones to give way.
-- neelandan, Dec 18 2001


this idea is pure genius, makes me wnat to own an establishment just for this! (+)
-- samosa_pirate, Nov 08 2008


Could you cause it to show shapes?
-- pashute, Aug 19 2010



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