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From: a0014246@unicorn.it.wsu.edu (mark fuller)
Subject: Re: Musle wire?
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Date: Sat, 21 Jan 1995 05:38:26 GMT
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Darin L. Reed (dreed@crl.com) wrote:
: Darin L. Reed (dreed@crl.com) wrote:
: : Steve Gillen (steve@phy-server) wrote:
: : : "musle wire".  Now I've read in this newsgroup (a while ago even) about
: : : some "nicro/niob/ni(something)" wire that could be stretched and would return
: : : to its original length when heated (something on those lines).  This wire

: : I think you are referring to "nitinol". It is mentioned in the FAQ for 
: : this group. 

: What a coincidence! Some kind soul just posted a big huge info file on
<deleted>

: Mr. Tracy R. Reed
: Aerospace Eng
: San Diego State Univ.
: treed@ucssun1.sdsu.edu

: -- 
: Tracy Reed
: treed@ucssun1.sdsu.ed
: dreed@crl.com

It should work great for your application if:
1.   you have some sort of latching mechanisim. to keep the wire pulling
     you have to maintain its temperature by keeping the juice flowing.
2.   you keep the wire out of moving air, the air would tend to cool it
     and require more power to maintain its temperature.

Given the rate at which this stuff operates, it should give you some nice
scale speed retract action. Unfortunately the main drawback of using this
material is that its electrical to mechanical conversion efficiency falls
short of your aircraft servos.  The main plus is compactness and weight
savings.

Mark Fuller
TANSTAAFL
(There Aint No Such Thing As A Free Lunch) 
