What order do cars go at a stop light ? ( Timing a light )

[Vman455]

https://www.youtube.com/watch?v=2ljFfL-mL70

[pete c]

I am surprised no one has come up with intelligent traffic lights yet than can look down the approach lanes with cameras and use image recognition software that would manage the lights to attempt to get cars through without stopping. There is nothing more frustrating that coming up on a deserted intersection and have your light turn red just before you get there even though nothing is coming the other way. Such a system would be very simple to design and save an enormous amount of energy and time. It would also save lives as it would reduce the number of people trying to "beat" a light.

If I were in charge, I would program it so that people approaching at wreckless speeds would have the light purposely go red on them. I would publicize this feature. The result would be people slowing to responsible speeds as they approach intersections. And there would be a whole lot less sitting at lights burning fuel, time and their patience.

The technolgy to do this has existed for a long time. Yet, we continue to use a braindead, expensive system that relies on digging up roads to bury sensors which don't change the light until after you have already stopped.

[oldtamiyaphile]

Originally Posted by pete c

I am surprised no one has come up with intelligent traffic lights yet than can look down the approach lanes with cameras and use image recognition software that would manage the lights to attempt to get cars through without stopping.

They exist, and use radar to predict traffic patterns, major interestions are sometimes monitored by humans who can adjust them to suit traffic patterns. In places with multiple lights in a row, they're usually linked (they turn green just before the traffic from the last set arrives) so as to allow blocks of traffic to move through each light unhindered.

Audi have developed a count down timer to tell you when the light is about to change.

[Fat Charlie]

Up hearabouts: Right turn treats red like a stop sign. Opposing left turns get the green together, then their respective straights. Sensors can shorten or eliminate unneeded left turn greens (when no one is there for a left), giving that green time to the straight that would have been waiting.

Whichever way it goes, even engine off I have my foot on the brake at a red so cars behind me can see brake lights. Even if I don't have the benefit of being able to see the other road go to yellow and then red, with my hand on the key I can have the engine running in the time it takes me to lift off the brake and move to the gas- so the experience is seamless to traffic behind me unless their windows are open and they hear me crank.

They see the light turn green, after a brief pause the car in front's brake lights go off and after a brief torque converter lag it starts moving. At least that's what it looks like. Like everything else in hypermiling, it works great if you can pay enough attention.

[markweatherill]

So the police officer said to me, I'm going to give you a little test, in the traffic light sequence, what comes after green, I said, I don't know, I'm usually gone by then.

[Focus-Ak]

Some places in Europe there are signs to switch off the engine, and then a light a few seconds ahead of the green light, cuing when to restart. EcoModders could lobby for this their own communities. Good for mileage, good for getting the general public tuned in, and good for the climate.

[digital rules]

Here in the DC area light sequence is all over the map at each intersection. You have to know beforehand how that particular light sequences. A few areas actually seem to care about moving traffic efficiently, but most don't seem to care.

Some areas that scream green the most generally have the most inefficient, poorly maintained systems. The libs in Arlington County, VA must do this to piss people off so they don't even want to drive anywhere. It's not like they don't have the money to make it efficient.