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From: rstevew@armory.com (Richard Steven Walz)
Subject: Re: PROPOSAL: A robotic Butterlfy!
Organization: The Armory
Date: Mon, 1 Aug 1994 01:32:56 GMT
Message-ID: <Ctu1Mz.LxJ@armory.com>
References: <1994Jul28.153808.22030@msuvx2.memphis.edu> <ELEQIM.15.0009A00F@herts.ac.uk> <nagleCtpoCH.DLy@netcom.com>
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In article <nagleCtpoCH.DLy@netcom.com>, John Nagle <nagle@netcom.com> wrote:
>ELEQIM@herts.ac.uk (Ian Munro) writes:
>>>So, what does everyone think?  I've thought it out extensively (although I
>>>admit I haven't set pencil to paper and worked out the physics of it), and
>
>>I was thinking about building a time machine but I haven't worked out the 
>>physics of it :-)
>
>       Anyone ever see the Wham-O (tm) Bird?  This was a wind-up 
>ornithopter, a machine that really did fly by flapping its wings.
>A '70s toy.
>
>       Paul MacReady's company, AeroEnvironment, once built a flying
>model of a pyerodactyl, but it was several feet long.  
>
>       MondoTronics, the shape-memory-wire people, sell a "bird" that
>flaps its wings but isn't powerful enough to fly, as a demo for their
>wire.
>
>       It's not a stupid idea to want to build a flying model 
>butterfly, but it's going to be tough to do.  Probably something with
>a wingspan of about three feet would be feasible.
>
>					John Nagle
-----------------------------
I would go for 8 or 10' span! The MacReady group already made a "Solar
Challenger" which flew like 180 miles and made it to over 10,000 feet. In
cases like this it is a matter of bigger is always easier from Galileo's
law of proportions. And you can have it seek thermals as well. Put a "peep"
transmitter on the capacitors or NiCads so you can track it. See how long
it will stay up and a what altitude!!! Orthnithopters are a pain in the
ass, though. I know it sounds great for mem-wire, but I don't know if it
could flap fast enough or convert heat efficiently enough. I'd try a solar
plane that would seek thermals and send telemetry for altitude and
tracking. Get it so high that it can ride the ridge thermals after dark one
way and then the other way at sunup!
-Steve Walz   rstevew@armory.com

