Path: utzoo!utgpu!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!rutgers!uwvax!puff!gumby!boettche
From: boettche@gumby.cs.wisc.edu (Michael Boettcher)
Newsgroups: sci.electronics
Subject: Hobby laser show system
Message-ID: <2110@puff.cs.wisc.edu>
Date: 6 Dec 88 18:51:40 GMT
Sender: news@puff.cs.wisc.edu
Reply-To: boettche@gumby.cs.wisc.edu (Michael Boettcher)
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Organization: U of Wisconsin CS Dept
Lines: 32


In the past I have contemplated building a laser deflection/show
system.  I would consiste of four electro-magnets(like the speaker
coils), but with the same polarity pointing towards the center.

A bar magnet, or another electro-magnet is mounted on a pivit, with a
mirror on the opposite end.  The polarity of the magnet end within the
fields of the four outer magnets would be the same.  The inner magnet,
connector, and mirror would all be very low mass, for low inertia.

The basic idea is that the four outer magnets would repel the inner
magnet.  This would force it into the center.  For  control, you would
decrease the field of one of the magnets.  This would force the inner
magnet in that direction.

Besides the problem of vibration senitivity for the overall system,
what kind of problems would there be for a system of this type.
I was wondering if the inductance of the outer magnets would prevent a
reasonable response rate.

Before responding with information that a > $500 part has more
sensitivity, realise that this is a $35 system, including scavanged 
electronics, and is intended as a hobby device.

Thanks in advance for your input.


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Michael Boettcher                 boettche@gumby.cs.wisc.edu
Student, Univ. of Wisconsin       107 N. Randall Apt. I
Applied Math, Engr. and Physics   Madison, WI 53715
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