Jim, one of the problems with the non military versions of GPS is the update
time. For a grain harvester it makes little difference because the distance
travelled in an update period is probably only a few short feet. However
with a car travelling at 200 mph (about 300 feet per second) the update time
of about 1/2 second means that you are going to go half the lengeth of a
foot ball field before you know yo are offf course. Add the drivers reaction
time of looking at the information to the update time with some time to reac
thrown in and you could have travelled a loooonnnnnngggg way before anything
actually changes. They make a GPS speedometer which needs only voltage to
work and works well...in a boat up to about 100 mph or so. Then the update
time becomes important again and the utility goes away. Now the military
version is fast enough to program inflight air to air anti aircarft missiles
to sneak up behind enemy aircraft without them knowing...the AWACS aircraft
can program way points in flight based on radar returns. Us civies don't
have that speed though...
mayf out in hicksville, Pahrump
----- Original Message -----
From: "Jim Dincau" <jdincau@qnet.com>
To: "land Speed List" <land-speed@autox.team.net>
Sent: Wednesday, September 01, 2004 7:30 PM
Subject: Navigation at Bonneville
> Hi all,
> I just read an article in the Sept. issue of Racecar engineering
about
> the Buckeye bullet electric streamliner. They have a GPS based system
> designed for use in grain harvesters to keep them running straight across
> huge Kansas grain fields. They take the GPS unit to the starting line and
> program the A coordinate. They then drive to the end of the track and
> program in the B coordinate. The unit goes back in the car and drives a
> display that has green LED's for on course and red LED's that tell you
which
> way to steer to get back to center. Works kind of like flying a localizer
> approach, its all in the drivers peripheral vision and they claim it works
> neat.
> Jim in Palmdale
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