Autonomous cars will lead to more sprawl -- WSJ

[casscorridor]

Autonomous vehicles won't eliminate public transport for the same reason why Uber won't. Sometimes it's more convenient to have a car pick you up, and other times it's easier to take a train. Traveling across the length of a city will probably always be easier by train. There is no way autonomous vehicles will be able to replace trains in cities such as London, New York, Tokyo or other sprawling megacities. There is simply not enough room on the road, even with efficiencies gained by automation. Moreover, even if these vehicles are non-emission/electric they can still be disruptive to walkable neighborhoods [[try crossing busy street of self-driving cars)!

Yes, maybe suburbs will function much more efficiently with autonomous vehicles, but many people will always desire to live in cities, which remain the most expensive places in the world to live [[obviously Detroit is an exception). Suburbs may be a growth area, but one reason is the expense of living in cities, not to mention the ill effects [[especially in american cities) such as crime and pollution which are not inherent to cities themselves, but rather effects of a greater socioeconomic context.

[ndavies]

Autonomous vehicles won't eliminate public transport for the same reason why Uber won't. Sometimes it's more convenient to have a car pick you up, and other times it's easier to take a train. Traveling across the length of a city will probably always be easier by train. There is no way autonomous vehicles will be able to replace trains in cities such as London, New York, Tokyo or other sprawling megacities. There is simply not enough room on the road, even with efficiencies gained by automation. Moreover, even if these vehicles are non-emission/electric they can still be disruptive to walkable neighborhoods [[try crossing busy street of self-driving cars)!

It's never easier to take a train than a car. Especially if you add another person.

What you're forgetting is autonomous cars will be able to form into trains. They will take up less space than individual cars would. Since they will talk to each other they won't need the huge following distances cars need today. Think of a train where the car could separate from the train pick you up and then reform with the next train. It leads to car like door to door convenience with mass transit like bulk.

Traffic lights will disappear as the vehicle will negotiate crossings with one another.

I can envision subway systems track ripped out, paved and turned over to self driving cars. You'd end up with way higher throughput in those tunnels. Just think how fast the subway would be if you weren't worried about the line your on since the car would always go point to point.

[Dumpling]

I guess I should throw in here that back in the 80's my Dad used to love to
dream up transportation systems in his spare time but when he ran his
particular pet idea past his GM managers they pointed out to him that
reducing the number of cars in use was not one of the company goals.

[bust]

It's never easier to take a train than a car. Especially if you add another person.

What you're forgetting is autonomous cars will be able to form into trains. They will take up less space than individual cars would. Since they will talk to each other they won't need the huge following distances cars need today. Think of a train where the car could separate from the train pick you up and then reform with the next train. It leads to car like door to door convenience with mass transit like bulk.

Traffic lights will disappear as the vehicle will negotiate crossings with one another.

I can envision subway systems track ripped out, paved and turned over to self driving cars. You'd end up with way higher throughput in those tunnels. Just think how fast the subway would be if you weren't worried about the line your on since the car would always go point to point.

I like the idea of organizing cars into trains that can separate as needed. And building tunnels for them to speed unimpeded through cities. I think that will someday happen.

But today trains [[the rail sort) are much faster than cars in dense cities [[New York, London, Paris, Madrid, Tokyo, São Paulo -- the list goes on). And while most would agree it's more comfortable in a car as a passenger than on a subway, many would prefer a subway to the stress and expense of car transportation as the driver, especially in those congested cities. So it depends how you measure "easier". I find subways and other trains are much easier most of the time, but not all the time.

And rail trains greatly reduce congestion, which makes life in cities easier overall. Each New York City subway car has an advertised capacity of roughly 250 passengers [[they get more crowded than that during rush hour). Most trains have 10 cars. That's 2500 people [[or more) moving relatively quickly from place to place in a space that is approximately one street lane wide and just over 600' long. A 2016 Prius is just under 15' long and seats 5. You can string 40 of them along a space as long, bumper-to-bumper, and have the capacity to move 200 people. New York without its subway and rail systems could not be the dense, walkable place that it is.

Tomorrow's driverless cars can be smaller than a Prius and still provide a much more comfortable ride than the subway, door-to-door. But not small enough to deliver the kind of efficiency possible from a good old 20th Century metro, measured in quantity of transportation delivered. Missing from the comparison so far are all the wide gaps between today's trains we won't have between tomorrow's driverless cars. But since we're talking about tomorrow and we'll have technology to reduce the gaps between cars, shouldn't we imagine we'll have technology to reduce gaps between trains too?

That said I'm really looking forward to driverless cars and think they will play an important role in our transportation future. Eliminating the need to drive will reduce stress and recapture driving time for other activities [[like commuters on regional rail already enjoy). Maybe they'll reduce travel time and cost too [[we'll have to wait to see). But I expect rail transit will continue to play a crucial role in our dense cities fairly long into the future. At least measured in technology years. It's speed and efficiency is hard to beat and will only get better [[too). If we invest in it.

Here's an article about how crowded NYC subways have gotten recently. Embedded in it is a 1930 short film from the NYC Health Commissioner addressing the problem of overcrowded trains that existed back then. Yes, comfort can [[still) be improved:

http://www.nytimes.com/2016/05/04/ny...-to-limit.html

Here are some specs on one of today's NYC subway cars:

https://en.wikipedia.org/wiki/R160_%..._Subway_car%29