Having used a GPS satellite receiver for navigation at sea I can't
imagine that this would really work as advertised. For one thing you
aren't getting continuous data, which makes any calculations of
instantaneous speed pretty shaky. As it updates the display every few
seconds, you get varying readouts along these lines: 6.1 knots, 5.9, 7.4,
0.0, 5.5, 3.7, etc. Part of the problem is that it's redoing the whole
position calculation from scratch each time, with a 30-meter error
radius. It does compare sequential readings to plot a vector and give you
a course readout, but on a motorway that could change from second to
second as you round a curve. It takes more than one satellite to
establish position and velocity -- a minimum of three, and five is
better. Certainly, the error could be reduced with advanced technology
(actually, the reason it is as high as it is, is that the US military
doesn't want more accurate info available and "scrambles" it), but I
would think that the best it could do would be to catch you going a
steady 10-20 mph over the limit on a straight stretch of highway.
Stoplight drag racing and parkway road racing would remain unaffected. At
least that's my guess. I suspect the whole concept is just the wet dream
of some control freak in the enforcement bureaucracy.
Scotty had this to say:
>
>On Wednesday, 5 January 2000 Jordan wrote
>Subject: No More Speeding in the UK?
>
>
>>>>>snip<<<<<<<<<<<
>>Can't vouch for anything in the article but I hope it doesn't catch on here
>>in the states.
>>>>>
>
>We saw a program on the TV news tonight and it explained this system and how
>it operates. A satellite communicates with a computer in your vehicle and
>places the car on a grid map { within 1 meter accuracy } of all the roads in
>the UK. Because the speed limits on all roads in the UK are known to the
>satellite it reads the speed at which the car is travelling and if y'all are
>speeding the satellite reduces the fuel flow to the engine, slowing you down
>to the posted speed for that stretch of road. This is projected to be an
>operational system within ten years. If they told us the truth on the TV
>that is.
>
>Big Bro' is watching over you!!!
>
>The claim is it will reduce road deaths by two thousand people each year.
>
>YMMV.
>
>L8R,
>
>Scotty,
>Adelaide,Australia.
>Who has exceeded the posted speed limit a time or two, chasing Eric in
>primrose down the road, for no good reason at all. 8^) Except it was fun!
>
>
>
>
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--
Max Heim
'66 MGB GHN3L76149
If you're near Mountain View, CA,
it's the red one with the silver bootlid.
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