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From: cdshaw@cs.UAlberta.CA (Chris Shaw)
Newsgroups: comp.graphics
Subject: Short-distance Ranging
Message-ID: <1990May25.192154.7565@cs.UAlberta.CA>
Date: 25 May 90 19:21:54 GMT
Sender: news@cs.UAlberta.CA (News Administrator)
Organization: University of Alberta, Edmonton, Canada
Lines: 22

I was wondering if anyone out there knows anything about short-range ranging.
Essentially, I would like to know if there are standard techniques for
getting scanned data that tells you distances of surfaces that are between
1 to 100 feet away. For example, if my ranging device is in a room full of
tables and chairs, I'd like the device to tell me the range of the scene
for each pixel.

Some people I've talked to preferred the passive approach, where you have
stereo TV cameras as the ranging device. To get the range, you do some kind
of trivial common-object finding to find the same object in both pictures,
and use trig to find their distance using the separation of cameras and the
separation of the objects in the two images.

The other approach is active, where you scan a laser or sound beam and collect
the echos.

Does anybody have any info on working (perhaps experimental) systems?
Is there a better newsgroup than this?
--
Chris Shaw     University of Alberta
cdshaw@cs.UAlberta.ca           Now with new, minty Internet flavour!
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