[AlanSE]

Even if the cars of the future won't be able to drive on all roads at all time, I don't see how it would matter all that much. Of course there will always be forms of rural driving where the terrain is unknown and there are limited options for sensor fusion available.

But that's not what's important. What's import is DC, LA, and many other metro cities that can't build more roads, but still need population and economic growth. For these cases, we're looking at something entirely different. If self-driving cars ever come to be a large share of the cars on the road, they become and unignorable option to lift the congestion ceiling on growth.

For major thoroughfares, you're looking at something close to a controlled environment. Even if there's rain or snow, you could have precision car location, relative to static beacons, and relative to other cars. There's no question where the lanes are, because all of these extremely major routes have detailed 3D models that all the algorithms have access to. I'm not saying we have that now, but compared to the other resource expenditures in self-driving technology, it's practically a trivial thing to do.

People don't need a car to drive them anywhere at any time. They need a reasonable option to get to work in the places where the jobs are. I would say that we're losing that right now, and self-driving cars are a solution, rain or no rain.

[zbentley]

> What's import is DC, LA, and many other metro cities that can't build more roads, but still need population and economic growth.

> People don't need a car to drive them anywhere at any time. They need a reasonable option to get to work in the places where the jobs are.

Mass transit. We know it works, and works well in circumstances you described. We know it increases in effectiveness in response to investment and added resources. Why bet on a long shot, if we know what works?

[AlanSE]

It works well in some circumstances, but not in those circumstances. In places where it does work, urban development had to change to accommodate transit. All of the existing development and infrastructure is so inflexible that these particular metro areas have no choice but to have the transit system change to accommodate.

The requirements seem pretty clear to me. The system has to be on-demand, able to accommodate sprawl, and lose little in terms of average speed compared to old expectations of personal car transit, and most importantly, it can't demand new physical roadway infrastructure.

I see how it's dubious that autonomous vehicles will fit this bill. Or it may be very challenging and take many decades. But let's be honest about the situation - it's the only option on the table.

[dralley]

> What's import is DC, LA, and many other metro cities that can't build more roads, but still need population and economic growth.

Mass. Transport.