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  • Stuck at an intersection, you always watch unfold the fundamental problem of traffic.

  • On green, the first car accelerates, and then the next, and then the next, and then the next, and then you, only to catch the red.

  • Had the cars accelerated simultaneously you would have made it through.

  • Coordination - not cars - is the problem because we are monkey drivers with slow reaction times and short attention spans.

  • Even if we tried getting everyone to press the pedal on 3-2-1-now would be challenging.

  • This dis-coordination limits how many cars can get through an intersection.

  • And when one backs up to the next, that's when city-sized gridlock cascades happen, taking forever to clear.

  • In general, more intersections equals more dis-coordination which equals more traffic.

  • This is the motive behind big highways: no intersections.

  • Splits and merges, yes. Intersections, no.

  • No stopping, no coordination problems, no traffic.

  • Well that's the theory anyway.

  • Intersections outside of a highway will back up onto it.

  • Again, because human reaction times limit how many cars can escape the off-ramp when the light changes.

  • But, even without intersections, there would still be traffic on the highway.

  • Traffic can just appear.

  • Take a one lane highway with happy cars flowing until a chicken crosses the road.

  • The driver who sees it brakes a little.

  • The driver behind him doesn't notice immediately and brakes a little harder than necessary.

  • The driver behind him does the same until someone comes to a complete stop.

  • And, oh look, cars approaching at highway speeds must now stop as well.

  • Though the chicken is long gone, it left a phantom intersection on the highway.

  • This is what's happened when you're stuck in traffic for hours thinking, "There must be a deadly pile-up ahead."

  • And then suddenly, the traffic's over with no wreckage in sight, to your relief if you're a good person and mild annoyance if you aren't.

  • You just pass through a phantom intersection, the cause of which is long gone.

  • And this phantom intersection moves.

  • It's really a traffic snake slithering down the road eating oncoming cars at one end and pooping them out the other.

  • On a ring road, a single car slowing down will start an Ouroboros of traffic that will last forever, even though there's no problem with the road.

  • If the drivers could coordinate to accelerate and separate simultaneously, easy driving would return.

  • But they can't, so traffic eternal.

  • On highways, traffic snakes grow if cars are eaten faster than excreted.

  • And they shrink if excreted faster than eaten, dying when the last car accelerates away before the next car must stop.

  • Now, in multi-lane highways, there needs be no chicken to start gridlock.

  • A driver crossing lanes quickly with cars too close behind is enough to birth the traffic snake that lives for hours and leaves.

  • It's this quick crossing that causes drivers behind to over brake and begin a chain reaction.

  • But we can make traffic snakes less likely by changing the way we drive.

  • Your goal as a driver is to stay the same distance from the car ahead as from the car behind at all times.

  • Tailgating is trouble.

  • Not just because it makes accidents more likely but because you as the tailgater can start a traffic snake if the driver ahead brakes.

  • Always in the middle!

  • This gives you the most time to prevent over-braking but also gives the driver behind you the most time as well.

  • And when stuck in traffic, this rule would get all cars to pull apart the snake faster.

  • That's the simple solution to traffic: getting humans to change their behavior.

  • Perhaps by sharing this video to show how and why traffic happens, why tailgaters are trouble, and how we can work together to make the roads better for all.

  • The End.

  • Except, yeah...wishing upon a star that people are better than they are is a terrible solution. Every time.

  • Instead, what works is a structurally systematized solution which is exactly what self-driving cars are.

  • Self-driving cars can just be programmed to stay in the middle and accelerate simultaneously.

  • They'll just do it.

  • The more self-driving cars at an intersection, the more efficient the intersection gets.

  • A solid lane of self-driving cars vastly increases throughput.

  • Hmm, actually!

  • If you ban humans from the road (which we should totally do anyway), you can get rid of the intersection entirely.

  • After all, a traffic light is just a tool for drivers on one road to communicate with drivers on another, poorly and coarsely.

  • Red equals "Don't go now, we are coming through the intersection."

  • Green equals "good to go."

  • But self-driving cars can talk to each other at the speed of light.

  • With that kind of coordination, no traffic light necessary.

  • Just as with the highway, the best intersection is no intersection.

  • Humans will never drive this precisely.

  • At the intersection, the fundamental problem with traffic that you watch unfold, as well as everything, is people.

  • So the real simple solution to traffic: is no more monkeys driving cars.

Stuck at an intersection, you always watch unfold the fundamental problem of traffic.

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B1 US traffic intersection highway driver coordination driving

The Simple Solution to Traffic

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    噹噹 posted on 2019/04/09
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