There are tons of self-driving metros in use across the world already so that idea is nothing new. https://en.wikipedia.org/wiki/List_of_automated_train_system

There are tons of self-driving metros in use across the world already so that idea is nothing new. https://en.wikipedia.org/wiki/List_of_automated_train_systems https://en.wikipedia.org/wiki/List_of_automated_train_system...