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There was a fun blog post several years ago, which has stuck with me ever since, and I think about it every time I'm stuck in a traffic jam. It was a one-man experiment in "fixing" traffic jams, by willfully slowing to the point where he no longer had to stop/start and could maintain a steady speed. He found that traffic behind him would "unkink", making the drive for everyone behind him a bit more pleasant/safe/consistent. He also found that many drivers would become angry at him, because he was going slower than the cars around him...but the cars around him were speeding up only to have to stop soon after to wait for traffic. Many people are, frankly, too stupid to be in control of a couple thousand pounds of rolling death...but, it'll be a challenge to get people to give up that control.

Hopefully, the ability to read, play games, watch TV, etc. while being driven to work will be sufficient to make people willing to let their smart cars take over the roads. As you note, traffic jams will become a thing of the past in most cases; self-driving cars can also factor in traffic data, weather information, etc. in ways that a human driver probably can't easily/effectively do, making them safer and more efficient in a lot of other regards.

s/Many people/Most people/

That's right. What you describe has been automated as an adaptive cruise control.

Almost a decade ago, traffic studies demonstrated that if only 20% of cars used adaptive cruise control, then traffic jams would be greatly diminished at then-peak carrying capacity. Or more cars could be carried on a particular road before traffic jams occurred.

Adaptive Cruise Control is currently a feature on many luxury cars, but will trickle down to mass market cars during the transition to driverless vehicles.

http://trafficwaves.org/

A similar effect is in play with 'metering light' systems - total throughput may be increased (counter-intuitively) by reducing localized traffic densities and smoothing irregularities in flow.

But people tend to perceive speed more readily than time to destination, and tend not to be very aware of total traffic throughput at all.

Not so.

When you go to driverless cars you can have higher traffic volumes on the road before you have to slow down. However the fundamental mathematical fact behind car jams is that you can pass more cars/second at high speed than at low. So if you have a road running near capacity at high speed and anything goes wrong, then you get a car jam that by necessity must travel backwards and grow in the process.

During peak commute hours, the volume of people who want to be on the road exceeds their capacity. As long as this remains the case, we'll continue to have car jams.

The idea is that automated driving, when it's good enough, increases road capacity enough that jams no longer occur. Capacity improves because all cars are now able to go much faster and with smaller distances between them, and without constant mistakes slowing other cars down.

The problem is that when you increase capacity, and decrease flow problems, you increase demand for that capacity. I find it very hard to believe that you can increase capacity enough to avoid jams in cities like Los Angeles.

This is my thought, too. I think self-driving cars are extremely cool, but I think that a lot .

Once self-driving cars are "the new normal", they'll be a lot more comfortable than regular cars. Which means that a lot of people won't think twice about a 75-minute car commute, because with internet access and the ability to read and an extremely comfortable chair, it won't be unpleasant to do so. And we will (because our reaction time is slow compared to a computer's) be able to raise the speed limits once self-driving cars are the norm: 150 mph highways where human-driven cars are banned, just as you can't take a bicycle on 65-mph highway. None of this is inherently bad, but I hope we won't be burning hydrocarbons to do it.

Ok, interesting business opportunity, time-based road pricing auctions integrated with automation. The roads keep flowing because people will pay others to defer their travel.

You can do that without self-driving cars though.

Jams are like a constant. If there are no jams, people can live further and further from their places of work and play without paying commute penalties, so they'll buy larger properties further and further out, until the congestion from the extra commuting becomes an issue again.

Whenever I'm in a traffic jam (expressway), it is usually caused by a lane closure. There are almost always signs posted alerting everyone of the closure, usually with more than enough distance from the problem area that no one should have difficulty getting over to an open lane.

What seems to me to be the problem is people follow a greedy algorithm. They cut into the closing lane because it's empty (or sparsely populated), then attempt to jet to the forced merge point then merge. At some point too many people do this, then you get two lines, one in the closing lane, one in the open lane that have to come to a complete stop and take turns.

Remove people's ability to follow a greedy algorithm and I predict you'll see a dramatic decrease in traffic jams due to lane closure.

>In a world in which every car drives "optimally", or at least without many of the human error mistakes that currently are made, many traffic jams will be a thing of the past.

Jams are not only capacity problem, but also sociological. People are willing to tolerate certain waiting time to get to fun/profitable location. If there are less jams and roads are free and gasoline is cheap, people will drive more.