Newsgroups: comp.robotics
Path: brunix!sgiblab!swrinde!cs.utexas.edu!uunet!hobbes!earth.armory.com!rstevew
From: rstevew@armory.com (Richard Steven Walz)
Subject: Re: Cables for robotic applications
Organization: The Armory
Date: Wed, 13 Apr 1994 12:38:41 GMT
Message-ID: <Co774K.3yn@armory.com>
References: <1994Apr4.180343.5901@aisb.ed.ac.uk> <CnuB8v.5pK@armory.com> <1994Apr12.192916.15598@osuunx.ucc.okstate.edu>
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In article <1994Apr12.192916.15598@osuunx.ucc.okstate.edu>,
Gordon Couger <gcouger@olesun.okstate.edu> wrote:
>In article <CnuB8v.5pK@armory.com>,
>Richard Steven Walz <rstevew@armory.com> wrote:
>>In article <1994Apr4.180343.5901@aisb.ed.ac.uk>,
>>Mark Wright <markwr@beryl.ed.ac.uk> wrote:
>>>Does anyone have information on the type of cables used for robotic
>>>applications such as low cost stepper motor arms or hands?
>>>Will steel do or do they need to be less elastic?
>>>Any information or advice gratefully received.
>>>
>If I were doing this I would try Kevlar you can get get it for about
>$10.00 per 100 yards at fishing tackle stores Specrta is also used for
>fishing line and also has very low strech but is a lot slicker.
>Good luck
>gordon
>
>
>                             Gordon Couger                            
>                             Biosystems & Agricultural Engineering              
>                             Oklahoma State University                         
>                             114 Ag Hall, Stillwater, OK  74074                 
> gcouger@olesun.agen.okstate.edu 405-744-9763 day 624-2855 evenings 
>    I do not speak for my employer
------------------------------
Yep, I know that kevlar is strong. But such things are usually stated by
"weight-comparison". I know that steel cable that is braided is strong and
very-low stretch, but how about the equivalent strength-mass in these
aramid fibers like kevlar. I know that strength often goes with elasticity!
Does the stuff REALLY stretch less than a strength equivalent amount of
steel/stainless steel??? Anyone know for sure? Sounds great and I'd love to
make lighter linear actuators that are cord/cable driven, if only THAT is
true. Remember that aramids are sufficiently lighter than steel that they
might take a larger diameter cord that still weighs less to achieve the low
stretch quality we want.
-Steve Walz   rstevew@armory.com

