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From: rbgorbet@kingcong.uwaterloo.ca (Rob Gorbet)
Subject: Re: Synthetic Muscles
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References: <alex.olshove.177.001B5781@gjpomail.doegjpo.com> <3n19f6$736@newsbf02.news.aol.com> <3n27mi$1vr@crl3.crl.com>
Date: Wed, 19 Apr 1995 19:43:39 GMT
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In article <3n27mi$1vr@crl3.crl.com>, jeremi@crl.com (William Jeremiah) writes:
> STel 00001 (stel00001@aol.com) wrote:
> : -- Just my two cents worth...
> : That last paragraph I believe is closest to what you want, if a metal will
> : do vs. a plastic. Nickel Titanium Alloy (NiTinAl) contracts to one tenth
> : its original length when a current is applied across such a wire.  Its
> 
> isn't this supposed to be "by one tenth of its length" as opposed to
> "to ten percent of its length"?

Yes, it should be.  The recoverable strain for NiTi depends largely on the
alloy, but it's generally accepted that if you want a significant amount of
cycles (in the millions) you should restrict the strains to 5%-8%.

> : pulling force is very good.  They are available in various lengths and
> 
> And you can make the pulling force better by using more than one in parallel
> can't you?

Yes, and you can use pulleys, lever arms, or SMA springs, to increase the amount
of motion you get from the wires.

Rob Gorbet.
SMA investigator.
