Will not gain acceptance
It would be far easier to make driverless trains which have far fewer variables that need to be controlled, but apart from a few short local services (e.g. airport shuttle transport) this has not been done, mainly because of public fear & distrust.
Unmanned commercial airliners have already been flown in a few test situations, and of course the military uses unmanned drones, but what is technically possible is a far cry from what would be deemed acceptable to carry passengers.
Biting the hand that feeds IT
