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<DIV style="PADDING-LEFT: 10px; MARGIN-LEFT: 10px" align=left><FONT
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size=2>John,</FONT></DIV>
<DIV style="PADDING-LEFT: 10px; MARGIN-LEFT: 10px" align=left> </DIV>
<DIV style="PADDING-LEFT: 10px; MARGIN-LEFT: 10px" align=left><FONT
style="BACKGROUND-COLOR: transparent" face=Arial color=#000000 size=2>>I've
been hanging around DPRG stuff for several years, hearing <BR>>about
odometry, knowing that I don't do it myself when I walk <BR>>around in a dark
room..</FONT></DIV>
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<DIV> </DIV>
<DIV>Is that completely true?</DIV>
<DIV> </DIV>
<DIV>When I walk around in a familiar dark room, I have a model of the room in
my mind.</DIV>
<DIV>I use walls to help realign myself in my model of the room.
Doorways and furniture help calibrate my position. I know about how
far I move with each step which is very helpful with getting across a room in
the absence of sensor information. Of course, the assumptions are incorrect
at times, feeling the "wrong" doorway and wondering why there is a wall
where the hallway should be or why there is a sink in the bedroom.</DIV>
<DIV> </DIV>
<DIV>I wonder if I was confined to a 2 wheeled differential drive platform and
had no vision (ever), what would happen then? </DIV>
<DIV> </DIV>
<DIV>- Ron </DIV>
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