Comment by Evgeny | Hacker News Reader

Comment by Evgeny | Hacker News Reader

I want to see a smart traffic control system.

Currently I'm only aware of the traffic lights which can sense when the car stopped next to the line and switch the lights accordingly.

I would like to see more. I would like the system to identify how dense the traffic is in all directions, including the right/left turn lines.

It would then adjust the duration of the green light according to the number of cars travelling in corresponding directions. It should also identify if all the cars that were waiting for the green light have crossed the intersection, and if there are no more cars it could turn then red light earlier.

So often I see the following: a jam is on a major road. A red line turns on, and a lonely car crosses a major road. The light is still red though for some time, with dozens of cars waiting for nothing ...

It's called a roundabout. ;-) http://en.wikipedia.org/wiki/Roundabout They help traffic flow lots in the UK and elsewhere around the world. Not a panacea though.

I've never seen a roundabout work well with high traffic though (in the US anyway), it has always seemed to me that they work amazingly well with low and medium traffic, but once they are full you end up with a single inbound street hogging it since everyone else has to yield.

Well you can have roundabouts with traffic lights. They work well in Chandigarh, India.

Everyone else would have to yield only if all traffic entering from that single busy inbound road was going all the way around the roundabout and exited onto the road it entered from. Since few cars do this, the odd single car on other entrances gets a gap where they pull out, often causing the busy road to queue while they pass, which in turn lets others out, etc.

I agree though, the heavier the traffic the less they work. Especially when morons pull out onto it despite seeing the exit is jammed and without leaving room for other lanes to cross in front and behind of them. Also, in the UK, many drivers fail to signal correctly, giving less clues to other drivers as to when they can pull out, e.g. if you're not signalling left as you exit a roundabout, you're doing it wrong! :-)

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