Newsgroups: comp.robotics
Path: brunix!news.Brown.EDU!noc.near.net!howland.reston.ans.net!usc!cs.utexas.edu!convex!constellation!osuunx.ucc.okstate.edu!olesun!gcouger
From: gcouger@olesun.okstate.edu (Gordon Couger)
Subject: Re: Opening/Closing Actuators
Message-ID: <1993Jul31.082328.29375@osuunx.ucc.okstate.edu>
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Organization: Oklahoma State University, Stillwater
References: <mott.744001905@sfu.ca>
Date: Sat, 31 Jul 1993 08:23:28 GMT
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In article <mott.744001905@sfu.ca> mott@malibu.sfu.ca (Jennifer Anne Mott) writes:
>Hello
>
>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.
>
>I'd prefer something that would move from one state to the other (i.e. from
>opening to closing) WITHOUT having to "reverse" or change the inputs.  (sort
>of like the auto reverse on a tape deck automatically starts to play in the
>other direction without human intervention.  Here I want something that does
>that without "electronic" intervention ... if that makes any sense)

The level wind mechinsim of a conventional bait casting reel (fishing reel) willdo exactly what you need. I has a double thread one running in each direction and changes direction when it comes to the end. One to two or maby a little more ttravel is common. I would thing that the petals should be open in the normal 
state and pulled down through a ring to close them.

I hope this helps,
Gordon
Gordon Couger 
Agriculture Engineering Oklahoma State University
114 Ag Hall, Stillwater, OK  74074
gcouger@olesun.agen.okstate.edu 405-744-9763 day 624-2855 evenings  
