>> Coordinating all these programmed traffic lights to keep vehicles moving is a problem.
Is that the goal of traffic light timings? I'm not sure. I think timings are more often used specifically to slow traffic (ie "traffic calming") or to prioritize one form or direction of movement over another.
I remember watching a BBC doc about traffic control in london. The operators all talked about helping vehicles move through the cities, but the policy makers spoke only of reducing traffic by essentially making travel more painful: "The easiest trip to manage is the one that doesn't happen."
The argument that ultimately, politics is what prevents real progress here, rings depressingly true. I heard a journalist explaining that in Berlin, it took 57 administrative steps to put a new traffic light at an intersection (Berliners have a very low opinion of their administration). I guess it's indirectly a political problem because since, as the article says, nobody can agree on how to solve a problem, there isn't the necessary political momentum to reshape the administration to do what needs to be done quickly.
I was going to say that this sounds suspiciously like something someone experimented with in Germany as well (http://stefanlaemmer.de/en/), but I've noticed that he's mentioned that example himself as well.
>If you can predict when cars will cross intersections, then you can prevent them from crashing even if they never stop; you just kind of decrease their speed. They almost never crashed in my simulation, and of course it was much more efficient
That's exactly right, the brake is the enemy of efficient driving and a system that can shirk this (by say, not accelerating to let other cars pass far ahead) would decrease fuel exhaustion by a helpful coefficient.
This is how we do it in India...just that the drivers optimise instead of the cars talking to the signals for a local optimisation.
Edit: originally commented too early after reading the selfish driver part.
As much as I like this is the complexity science actually beating the traffic jams or just discussing his unfulfilled desire to do so which is currently blocked by politics
most people I know know very little about complexity, and I'll be showing them this article, thanks for sharing!
MOVA, Needs to be more than 50m or just switch to UTC. Sigh - Traffic Engineer.
Sad thing is this probably won’t work in the real world due to nimby types.
This is awesome, I built a toy ML project which ran in a simulated traffic system as a way to explore ML. Like the author, if the individual traffic lights modulate to traffic density "waves" emerge in the simulation of vehicles going through intersections. And, as noted by the author, you only have to do this at the light, it doesn't need any other inputs except an ability to recognize cars coming toward it.
One of the surprising thing is its "disaster" response. Which is to say to totally wipe out like 6 intersections to through traffic. The lights with a way around begin cycling more rapidly, this makes the flows that the lights downstream "see" have more openings in the direction of the exit so they start cycling more vehicles that way, and if the simulation is set up so that vehicles begin to diverge to open roads if enough time has passed with them sitting at an intersection. All of the cars begin to flow around the obstruction.
I couldn't get my "car model" to do an illegal u-turn (as I've seen many cars do in real life when stuck at a traffic light where they could go back the other way) so there were always vehicles that remained stuck trying to get through to impenetrable divide but it was a nice example of emergent behavior from a complex system with automaton type rulesets.