So what if we eliminate some of the hard problems, like steering, traffic, pedestrians, and setup guided routes specifically for automated vehicles? All you would need to control is signaling and the throttle/brakes. You could even couple multiple vehicles together for more capacity! Seems like an idea ripe for implementation. /s
What's funny is that the railroads of the US were mandated to implement this (PTC) by the end of 2018 and have almost universally blown the deadline.
Caltrain tried to roll their own implementation, got caught with their pants down, and iirc are now trying to save face by switching to one of the standard vendor developed systems