Newsgroups: comp.robotics
Path: brunix!uunet!news.mentorg.com!davidr!davidr
From: davidr@davidr.mentorg.com (David Ransier)
Subject: Re: Table top Hovercraft know how wanted.
Message-ID: <1992Nov30.155454.7809@news.mentorg.com>
Sender: davidr@davidr (David Ransier)
Date: Mon, 30 Nov 1992 15:54:54 GMT
References: <1992Nov23.202310.11523@hpcvca.cv.hp.com> <VNVsuB2w165w@galsci.uucp>
Nntp-Posting-Host: davidr.mentorg.com
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In article <VNVsuB2w165w@galsci.uucp>, galsci!mpearce writes:
|>  yee@edison.seas.ucla.edu (John Yee) writes:
|> > Hello robot builders, have you any experience making small, say 6" diameter
|> > maximum, hovercraft?  If so, please post/email your experiences.
|> >     jy, yee@seas.ucla.edu - "The man with no .sig"
|> 
|> I may be easier just to buy one of the pre-assembled RC hovercraft kits.
|> Tyco makes two, a large one (about 14" x 6" x $100) and a smaller one
|> (10" x 5" x $70). Both have one lift fan and two thrust fans, each
|> with forward and reverse.
|> 
|> I bought the large one and ran into two problems. First the battery charge
|> only lasts about 8 min., with a 4 hour recharge time. Not a lot of time
|> to get any "research" done. The other problem is that the lift fan is 
|> barely powerful enough to lift the hovercraft, so it only works on smooth
|> flat surfaces, like conference room tables. I tried running it out in the 
|> parking lot and the front lip of the skirt kept catching on the pavement
|> and wrapping under the hovercraft. If you start mounting sensors in the 
|> thing performance will be even worse.
|> 
|> I started to replace the electric lift fan with a .049 Cox engine, but
|> haven't touched it in a few months. Probably after Christmas...
|> 
|> 
|> -----------
|> Mike Pearce, Knowledge/Interface/ToolBook Engineer
|> Galaxy Scientific Corp., Information Division, Atlanta GA
|> (404) 491-1100 or mpearce@galsci.uucp
|> 
With just a little more money, well, maybe a little more than a "little
more money", you can over come the four hour limit.

I was playing with RC cars for a while and bought a fast charger for my
batteries.  Also I had two sets of batteries.  They will quick charge in 
about 15 minutes.  With one battery always charging and the need to tweak
a little between flights, you'll waste very little time waiting on the 
battery.

Also, you'll find the chargers that work only from a  car battery to be 
cheaper than the ones that also plug into AC (they have less circuitry
to pay for.)

David Ransier
