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I don't buy the raising speed limits thing because the tech is actually much easier to regulate and enforce than human drivers.

I guess the example is Uber/Lyft, but remember that those went to a vote and the vote passed. And if non-AVs are banned from cities, wouldn't our cities be much more bikeable and safe? How many pedestrians are killed again by human drivers?

Trains are not magical, they also suffer from congestion issues, in fact moreso than roadways because they generally cannot pass each other. If a city were pure AVs, you could absolutely have train-size AVs for key arteries/events and still enable much more flexible point-to-point travel.

AVs can and will have pooled ridership in the near future.






Trains can pass each other! I see it happen all the time in Japan.

It's easy to enforce speed limits on AVs, but also easy for AV proponents to argue that speed limits are obsolete and unnecessary when cars have millisecond reaction times, a legacy from back when sluggish humans piloted vehicles around. It's hard to say what the future may hold.


It's crazy that people are so pro-train. Imagine if they were invented now, the idea of building train tracks throughout cities would be laughed at. Trains cannot turn to avoid someone and their stopping distance is awful making them incredibly unsafe unless operated on tracks that completely exclude humans.

If trains were an AV they'd never be approved. The only thing they have going for them is passenger density but that is now easily achieved with battery electric vehicles.

The smart thing to do is actually pave over existing tracks and allow high-density AVs exclusive use to those thoroughfares. You could achieve much higher utilization and have routes that go more direct since they could exit the thoroughfare to load and unload rather than block it.


Trains are vital to a point that the government instantly shut down a train strike over paid sick days. They are still the best cost value for transporting cargo long distances.

Trains with current car-enabled cities would be laughed at because they are car enabled cities. Yes, you would be laughed at for using the wrong tool for the job. That's why these arguments also involve reshaping the job itself to be more efficient. It's still a popular idea for Californians to go from Los Angeles to San Fransisco three times as fast than any car ride could hope for, so it's not like people don't see the immediate benefits of how trains can bridge together cities.

>The smart thing to do is actually pave over existing tracks and allow high-density AVs exclusive use to those thoroughfares.

ignoring the details the video already counters against this: This would be a political landmine on multiple fronts. For the exact same reasons the high speed rail project above is taking decades instead of maybe 1 decade.


It's rare that I encounter such a fascinatingly different viewpoint to my own that I'm staggered to consider how it could have been arrived at.

Trains don't need to turn to avoid people because their motion is entirely predictable. You can stand one meter away from a passing train with no fear, because you know exactly what its trajectory will be -- it's built into the track under your feet. This is why people are comfortable walking next to trams in crowded areas, whereas they have to give cars a wide berth -- you don't know if they're about to steer into you. For this as well as several other reasons, trains are orders-of-magnitude safer than road vehicles. Especially when weighted by passenger-miles, because then we're comparing the collision frequency of one train against that of hundreds of cars (or even a thousand -- one shinkansen train comfortably carries about 1300 riders).

And yes, because the passenger density is so high, noise level is low, and the traffic is so intermittent and predictable, this does allow the construction of both separated-grade tracks (whether elevated or subway), and also protected crossings for at-grade trains. The safety level is so high that people rarely get hit by a train by accident -- more often suicide or crime is involved. And better safety features, like barriers at stations, can go along way to reducing these remaining risks. It's hard to imagine these kind of safety features being feasible for AVs.

Battery electric vehicles do not and will not come close to the passenger density of trains. Trains also afford higher comfort (it will probably be a long time before robovans provide washrooms with running water!).

By moving between fixed stations, investments in fixed infrastructure can be made with confidence to accommodate the high throughput of people. The routes naturally become direct not because trains stop at every single block, but because travel destinations naturally move close to the stations rather than sprawling out. And because people stepping off a train don't bring a car with them, these areas are intrinsically walkable and pleasant, and don't need to be cris-crossed with high-traffic roads that consume much of the available space.

If you ever have a chance to visit Japan or the Netherlands, let me know if you update your ideas about trains.


I haven't been to the Netherlands yet, it's on my list, but I was just in Japan a few weeks ago.

The thing that surprised me most about Tokyo was actually how generally crowded the trains were. It seems obvious that they should be running near twice as many trains in general and especially during rush hour. The tracks were still mostly empty compared to streets. While everyone was super considerate, it was still relatively low comfort traveling with a kid because of the uncertainty around getting a seat.

Why couldn't we build barriers along AV roadways and code them to drive an exact path? It's actually much easier to code an AV to act like a train than this freeform driving that they are doing. They could go into train/convoy mode to utilize the train infrastructure then back into car mode to take a side street.

You can easily put bathrooms and running water on AVs if it makes sense.

I do agree about having the nice walkable areas near stations, but was somewhat surprised that car right-of-way was still super dominant in Japan. Like the Shibuya Crossing, you have thousands of people all scrambling across then cramming onto the sidewalks while vehicles get 70% of the right-of-way timeslice. I'd actually flip that so that peds are the primary street users and AVs must yield.




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