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From: alex@vmars.tuwien.ac.at (Alexander Vrchoticky)
Newsgroups: sci.electronics
Subject: Re: X-Y detection of moving metal ball?
Message-ID: <2409@tuvie.UUCP>
Date: 17 Apr 91 13:29:09 GMT
References: <14815@mcdphx.phx.mcd.mot.com> <2404@tuvie.UUCP> <1991Apr13.165525.24986@milton.u.washington.edu>
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whit@milton.u.washington.edu (John Whitmore) writes:

>>silhouette of a ball with a comparator. You can find the first pixel
>>that is lighter or darker than a certain threshold

>	It should be a LOT easier than pattern recognition; remembering
>that a convex mirror produces a virtual image, just use a point source
>illuminator and put the polished ball in a black environment.  The
>image of the light source will be a tiny point inside the ball.
>	

it sure is easier. but it does not solve the problem.
not unless you are willing to turn an entire lab into a dark-room.

--
Alexander Vrchoticky            | alex@vmars.tuwien.ac.at
TU Vienna, CS/Real-Time Systems | +43/222/58801-8168
"at the end of the day i guess you are what you eat" (monie love)