Newsgroups: comp.robotics
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From: mott@kits.sfu.ca (Jennifer Anne Mott)
Subject: Re: Opening/Closing Actuators
Message-ID: <mott.744420798@sfu.ca>
Sender: news@sfu.ca
Organization: Simon Fraser University, Burnaby, B.C., Canada
References: <mott.744001905@sfu.ca> <1993Jul31.082328.29375@osuunx.ucc.okstate.edu> <nagleCB1HGv.v8@netcom.com>
Date: Tue, 3 Aug 1993 23:33:18 GMT
Lines: 42

nagle@netcom.com (John Nagle) writes:

>>I'm trying to find some kind of actuator that could be used to both open and
>>close something shaped vaguly like the petals of a flower.
>
>      Can you say more about the application?  It's not clear whether you
>want to actuate something the size of a flower or the size of a 
>power shovel clamshell bucket.

Sorry :-)  I want to actuate something roughly the size of a flower, or
just a bit larger.  Maybe as large as a sunflower in diameter at most?
(I'm not sure yet ... it's a "small project" idea, but I wanted to see what
was potentially available to do it with before going any further with it)

>      Mondo-Tronics makes a "memory metal" actuator, and they have a
>demo unit which slowly and quietly flaps the wings of a decorative bird
>model.  That's at the low end of the power range.

Yes, I've heard of this ... Nitanol wire I believe.  Someone else has
provided me with the address for Mondo-Tronics.  This is definitly one
option ... but I can see that this would keep the application *very* small.

I'm looking for something that isn't terribly expensive ... something that
an average student type could afford (thats me :-)  I also am looking for
something with a reasonably simple method of application.

>      There are hundreds of mechanical linkages that have been designed
>for producing reciprocating motion.  This was a classic problem of the
>steam-engine era, and any book on mechanism design will have some samples.
>Many are variations on the crank, but there are some wierd ones.
>Outfits like Small Parts Inc. and Berg sell standard mechanisms for
>various motions.

Thanks for the suggestions.  You wouldn't happen to have an address for
Small Parts Inc. and Berg would you?  Perhaps somewhere to order catalogues
from?

-- 
Jenni Mott                      | When in trouble,     |  All comments are
(mott@sfu.ca)                   |    When in doubt ... |       MINE!! 
Computer Engineering Student    | Run in circles,      | So don't give THEM
Simon Fraser University, CANADA |    Scream and Shout! | any of the credit!
