I assisted a team from Canada and saw some
practicle results of Differential GPS.
When it was working well it had a resolution
of 3-4 centimeters. More than enough for
mowbot applications. Novatell allowed
teams to borrow GPS equipment and allowed
a 50% discount to educational institutions.
The GPS was hard to resolve near tree cover.
Even if not directly covered overhead,
the trees could block out satellites.
RF modems were common (9600, 14200 baud)
but cost about $800 each; usually they
were borrowed from industry.
Between the cost of the Differential GPS,
the RF modem to send the GPS correction
information and the difficulty with tree
cover Differential GPS currently seems
incompatible with low cost mowbots :(
-Monta Elkins
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"And the world will be better for this: That one man scorned and
covered with scars, still strove with his last ounce of courage;
to reach the unreachable stars"
System Administrator - Blacksburg Electronic Village - www.bev.net
monta nospam at bev.net - http://www.bev.net/project/people/monta
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