"Self-organizing" traffic lights that can adapt to changing traffic flow

[codyg1985]

An interesting study (PDF) about new traffic signal systems that can adapt to changing traffic conditions through a computer shows that delay can be reduced up to 30%:

At the moment, traffic engineers normally tailor the cyclic operation of lights to match known traffic patterns from the recent past. Lights on main roads stay green longer during peak hours, for example. But so far it requires supercomputers or engineers, who do the tuning.

Lämmer and Helbing wondered if traffic lights might devise better solutions on their own, if given some simple traffic-responsive operating rules and left to organise their own on-off schedules. To find out, they modelled the flow of traffic as if it were a fluid, and explored what happens at road intersections, where traffic leaving one road has to enter another, much like fluid moving through a network of pipes.

[english si]

Southampton, the traffic-light capital of the UK (and I think topping the list of European cities by signals-per-head is still Southampton) has had a semi-automated smart traffic control system for about 35 years, gradually becoming more automated as computers get better and the road network got changed more and more to hand more control to the control centre. A system of cameras and sensors look at traffic flow, and a central computer changes the cycles of the traffic lights. I'm not sure whether the system being proposed is any more advanced that Southampton's.

It kinds of works, but it's not great for cyclists (who often don't trigger the sensors) and people moan about congestion quite a bit - though I feel that's probably more to do with geography and the road layout than anything else. Then again, signalising all sorts of junctions that wouldn't be elsewhere in the UK doesn't help - turning roundabouts into complex signalised junctions is 6 of one, half a dozen of another in my book. But there are excessive amounts of traffic signals in the city to make it easier for the system.

[SidS1045]

New York City DOT tried doing something like this on Queens Boulevard many years ago.  Don't know what happened to it, however.

[roadfro]

I know the FAST system in the Las Vegas area did a study along a stretch of Boulder Highway (SR 582/old US 93-95) where they looked at both engineer-optimized network and an adaptive signal system network that adjusts on its own. Not sure what the result of that study was...

That corridor is getting BRT now, so there's probably other signal timing elements coming into play.