From: Keenan Crane
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Subject: Re: Designing an Input Device
Date: Mon, 14 Oct 2002 12:46:13 -0500
NNTP-Posting-Date: Mon, 14 Oct 2002 12:43:26 CDT
Organization: University of Illinois at Urbana-Champaign
Ok - I was looking at those Polaroid sensors and got another idea -
Since the sensors are unidirectional you could have three of them, one
oriented on each axis, in your controller box / "pointer." You then
have a half cube which you use your pointer in so that each of the
sensors bounces off one of the cube walls and gives you a reading of
distance. After that, it couldn't be easier - normalize your readings
by the response curve and you have your x, y, z coordinates. I don't
know yet what the refresh rate / spatial resolution on these things is,
but I expect it should be adequate for my purposes.
Now if only I knew how to build it...
Jim Pennell wrote:
> ----- Original Message -----
> "Keenan Crane" Wrote:
>>I know very little about electronics design and manufacture,
>>so please forgive me if this sounds a little trite.
>>I would like to construct an input device for a computer
>>which determines the coordinate of a point in space.
> Hmmm.... How far from the sensors, and how accurate does it have to be?
> I recall Polaroid has, or used to have, the sonar focus sensors for sale.
> They may be good enough for your purpose, but a few details as to distance
> and accuracy would be helpful.
> For example, how large is the object you want to locate?
> Jim Pennell