I'm curious what happens when you have highways filled to capacity, and then more cars are added.
A busy highway moving smoothly at capacity is like a super-cooled fluid. As long as nothing goes wrong, it can last, but the second you introduce some delay, somewhere, you wind up with a rapidly expanding solid (ie traffic jam). Intelligent cars boost the capacity of smooth traffic more than they do the capacity of bumper to bumper slow traffic, and hence the transitions from "awesome" to "oh shit" should be much nastier than they are now.
The traffic jams of the future could make our current ones look tame.
I live in Seattle, and traffic during rush hour here is a nightmare.
There are perhaps 5 key routes of getting in and out of downtown. Last summer, one of these was blocked by an accident [1], leading to a complete gridlock on the highway for five hours, and downtown traffic was taking roughly ~30 minutes to travel a block.
It would be relatively easy to cause five significant wrecks on each of these corridors. Rent a moving truck and crash it into several vehicles at high speed. Traffic would be so congested, it would take hours for emergency crews to get to the scene. If you did this during morning rush hour, I imagine you could shut down a lot of the city for the day.
Traffic jams spontaneously occur before roads reach theoretical capacity. You should look up information yourself on that if you're curious (because offhand I'm not sure what to search for).
>Even better is to get the cars off the road by having good flow and not jamming it up.
This is not practical in most cases of congestion, which are caused by the number of vehicles exceeding the road's capacity. There is no other choice after a certain point, vehicles will begin to pile up and speed up and slow down creating the traffic waves.
That video is correct for only a minority of times where the road capacity has not been met, but people are accelerating and decelerating too fast causing the traffic waves.
However, during times of too many vehicles on the road, such as rush hour, there is nothing anyone can do, other than use as much of the road as possible (i.e. less empty space).
How to slow down traffic even more: dig trenches across the road. Remove bridges and culverts, use fords instead. Block lanes with ornamental sculpture. Block lanes with "DEAD END" signs. Remove navigational signs generally. Install caltrops. Remove drains. As an extension of school lunch programs, routinely issue free traffic cones to small children.
I've been in one such jam in the Netherlands where there is an upper limit at which everyone consistently (for the most part) drives their cars on the highway. So I don't know if that would help.
Nice. I've wanted to do something like this, as I have a theory about the car pool lanes being worse for traffic. When traffic is bad, car pool lanes are just as backed up typically.
When someone wants to get in the car pool lane upon entering the highway, they tend to do so fairly quickly. This can cause a shockwave as someone flies from one side of the highway to the other. The same thing can happen in the opposite direction when a carpool lane driver needs to get off, and this issue is compounded even more since you can't always (legally) exit the carpool lane.
So I thought it'd be interesting to play with a simulator like this, add/remove carpool lanes, or lanes altogether, and see what results.
They'd have a revolt on their hands in short order, around here, and I suspect in most places. You can't handle enough traffic on the parts of our highways that go through the city, while maintaining the kinds of gaps that would be necessary to avoid these sorts of wrecks (well, the later pile-ons, anyway). Commute times would shoot up and areas that don't usually experience congestion would become intolerable around rush hour, if people really started leaving that much space, consistently.
Which is, perhaps, one of many arguments against having so many people on the roads to begin with, but that's what we have.
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