In response to the recent trend of Nitinol™ inspired innovation, I'm compelled to assert that the jacket modeled by Marty McFly in "Back to the Future- part II" is technologically feasible at present.

As prior art has dictated, clothing must be constructed with a particular size and build in mind. No more.

Nitinol has unique characteristics, which allow it to change its molecular structure at a relatively low temperature, (approximately 140 degrees F) which can be induced either by external exposure to heat, or passing a current through it, causing it to seek memory with as much as a 40% linear contraction. Nitinol's flexibility is unparalleled by other materials in a "cold" state as well. The reaction time is generally in the range of one second for full contraction.

Given these unique characteristics of Nitinol, and its availability in strand diameters readily applicable to weaving, it is possible to create a weave of fabric (probably a knit, *spandex, etc.?* which will stretch and contract to accomodate a range of states while maintaining a "tidy" appearance) with, say, perhaps a 1% or so Nitinol content, which can "shrink to fit" (not to infringe on Levi Strauss and Co.'s trademark) the wearer. This would be facilitated by a battery and microprocessor control incorporated into the lining of the garment, passing a timed-increment output of current sufficient for your needs upon demand.

If your "slightly larger friend" needs to borrow a jacket, you simply stretch the jacket back to its fully-expanded state, and re-shrink it to fit your friend.

Nitinol's memory-seeking ability actually improves with repeated stretching and contracting, so the more times the size is changed, the better the garment's ability to adapt will be, without worry of "wearing it out". I think this could be especially handy if provided in emergency survival kits, etc., eliminating the need for user-specific size requirements.
-- X2Entendre, Dec 31 2002

"The shirt that rolls its own sleeves?" http://www.abc.net....stories/s336668.htm
£2500 for the prototype. [egnor, Oct 05 2004, last modified Oct 21 2004]

"Your jacket is dry!"

140 degrees could be a bit warm...
-- RayfordSteele, Jan 01 2003


I considered that, but it's for a duration of about one second, and most jackets are insulated, so I doubt the wearer would even feel it. Probably more comfy than [UnaBubba]'s bra, no? No offense intended, [Una] <G>
-- X2Entendre, Jan 01 2003


Ok, that does it. What the hell is <G> ?
-- 2 fries shy of a happy meal, Jan 01 2003


for goodness sake, UB wears a bra? now that surprises me.
-- po, Jan 01 2003


"Never work"? Thanks for the fishbone, [egnor], but I respectfully beg to differ. The material I've suggested is a knit, something already known to have an elastic range equal to or greater than that of Nitinol, that will expand and shrink *with* the Nitinol. I *have* played with Nitinol. The material doesn't behave as you've described. When the heat is removed, the material *can* be stretched, it doesn't just naturally return to its pre-heated state. As an example, a .010" diameter Nitinol wire is able to contract with approximately 930 grams (2.04 lbs) of force when heat is applied. When the heat is removed, it remains contracted until stretched. It will take about 450 grams (.99 lbs) of force to re-stretch the .010" diameter wire (this value is hard to "nail down" as the martensitic threshold of stress is very dependent upon temperature, but this is the approximate minimum force requirement at around 50 degrees F, the actual force required will most likely be higher). When many such wires are inter-woven in a fabric at a regular interval, I am *hypothesizing* (not actually having woven this material) that the force required to re-stretch the material will be more than sufficient to give it the dimensional stability which you claim it will lack. Even if we had only 3 or 4 wires in a sleeve (which there would undoubtedly be more) can you actually imagine the sleeve just re-stretching itself? Thanks for your annotation though, it forced me to re-check a few figures.
One question... Have YOU played with Nitinol lately?
-- X2Entendre, Jan 01 2003


Obviously, I haven't got *all* the details worked out, but considering all the various types of weave, I'm not yet convinced that there exists no compatible fabric to facilitate this. Even if a bit of bunching occurs, perhaps some may find it to be fashionable? At any rate, [egnor], it's obvious that you've given some serious consideration to my idea, and I thank you for that.
-- X2Entendre, Jan 01 2003


Apparently lots of people are working on nitinol-laced fabric. There are various issues. Link, and search for "nitinol fabric" yourself if you're curious.
-- egnor, Jan 01 2003


Hey, no fair [egnor], you deleted your previous annotations. That kinda' ruins the flow of the discussion, [UB] and I appear to be talking to ourselves now.

Yes, [UB], I totally agree... even at bulk prices, it's probably going to be a few dollars per foot... but... we're not here to price things, just to dream them up, right?

Thanks for the link [egnor], I wasn't aware of that. Pretty neat though.
-- X2Entendre, Jan 02 2003


Baked.

(1) Shrink to fit jeans were common in the '70s/80's (I forget)

(2) Spandex

But none of these look good, unless you are a baywatch actress.
-- FloridaManatee, Jan 02 2003



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