"Neil Williams" wrote in message
...
On Tue, 01 Jun 2004 21:03:10 GMT, "mookie89"
wrote:

Inductions loops, yes. But.....
Here in Illinois, IDOT (Illinois Department of Transportation) may set
the
control device(s) for peak/non-peak hours. So even though there is a
loop,
it may take up to two minutes to cycle through depending upon what time
of
day it is. Two minutes, 120 seconds, when no one is on the cross street
is,
as you know, an eternity. snip

This is rather silly. Applied properly, induction loops will override
the cycle and give right of way to the road on which there are
vehicles over the one where there are not. Only if there are vehicles
on more than one of the roads feeding the junction is it necessary to
revert to a traditional pre-programmed cycle.

This kind of thing is also used to give buses priority at certain
junctions, for example. If a vehicle is detected in the bus lane, the
lights are automatically changed in its favour so it shouldn't even
need to brake. This has been going on for a while - the intersections
on the 1970s Runcorn Busway are so fitted, I believe.

Neil

--
Neil Williams in Milton Keynes, UK
To e-mail use neil at the above domain

Silly, I agree. And very frustrating. Just last night it happened to me.
Again. I went in to the city to catch a night baseball game (Chicago Cubs,
of course) and the train got back to my community at midnight. As I pulled
up to cross the major road, my light was red but the opposing traffic had a
left turn light. I had to sit through the entire cycle which allowed a
green on the cross street but not one vehicle was there! I finally got my
green light. It would just seem that with today's technology they could do
a better job.

Also, our emergency vehicles have what's known as an OptiCon System on
board. Basically it is a very specific white high intensity strobe lamp
aimed slightly upward. At many USA intersections a little periscope
appearing apparatus is mounted just above the traffic light. That's the
OptiCon sensor. When the police car/ambulance/fire truck emits the strobe
pulse, the signals quickly favor the emergency vehicle.

Rich