Newsgroups: comp.robotics
Path: brunix!uunet!zaphod.mps.ohio-state.edu!saimiri.primate.wisc.edu!usenet.coe.montana.edu!news.u.washington.edu!uw-beaver!fluke!oak
From: oak@tc.fluke.COM (Peter Oakley)
Subject: Re: Table top Hovercraft know how wanted.
Message-ID: <1992Nov30.191208.7825@tc.fluke.COM>
Organization: John Fluke Mfg. Co., Inc., Everett, WA
References: <8722@lee.SEAS.UCLA.EDU> <piggy.722560670@newsroom.utas.edu.au>
Date: Mon, 30 Nov 1992 19:12:08 GMT
Lines: 38

piggy@hilbert.cc.utas.edu.au (La Monte Yarroll) writes:
>I built a 12" hovercraft for operation on extremely smooth surfaces.
>Rather than a fan, I used compressed CO^2.  I used the oxidant
>regulars from two mini tourches (the butane/nitrous oxide tourches
>that Radio Shack used to sell).  The CO^2 cartriges were of the type
>used in selzer bottles.
>The base of the hovercraft was a piece of plexiglas, about 1/8" thick,
>cut into a circle and carefully polished.
>I drilled a small hole in the center, just large enough to fit the
>fine tip of the tourch.  I made a shallow indentation on the bottom of
>the base about 1" diameter around the hole in the center.
>Setting the regulators at a very low setting, the device would move
>freely accross a level lab table for several minutes.  Setting higher
>  [... etc]

My sister used something very much like this with a sheet of
plexiglas, but the gas source was an AA battery powered hobbyist's
aquarium pump mounted on the plexiglas..  It was smaller than 12" 
diameter, more like 6" to 9" in diameter.  She used it on a large 
polished granite slab, in Stanford's Aerospace Robotics Laboratory, 
to simulate the 2D motions of robots in zero gees.  I imagine it 
could run for much more than several minutes; probably a couple of hours.

Battery powered aquarium pumps are available from aquarium shops,
of course, but I've also seen them in fishing stores and catalogs
for keeping baitfish alive and healthy.

Before you invest in the battery pump, you could do some experimenting
with an AC powered pump you already have or can borrow.

 
-- 
Peter Oakley  M/S 241F			oak@tc.fluke.com
Staff Engineer				(206) 356-6254
CAE/CAD Coordinator
POB 9090
John Fluke Mfg Co Inc
Everett, WA 98203-9090   USA
