The day is already here, Google’s self-drive cars have logged over 140,000 miles so far. Yes it’s a Prius, no it isn’t controlled using an iPhone.
GPS won’t tell you about a pedestrian trying to cross the street, or the slower car in front of you.
Hence the “sensor industry”
But we’re discussing a current state of the art Prius. Unless you’re in it or next to it you’d be driving blind.
That doesn’t mean the car wouldn’t get to the destination 
We are also discussing someone else’s solution, not mine. Mine came with an operator alongside the Prius. Maybe (probably) there is more use of the existing electronics to be made than the mythbusters approach I suggested, but keep the nearby operator and use the electronics onboard as needed and you are good to go today.
I only said the day of driverless cars is coming, not that it is here.
Relatively blind, but it has plenty of sensors. Here are the options for a current state of the art Prius:
A driverless Prius is very possible, so possible it has been done already and works well by all accounts. No accidents have happened involving the driverless Priuses(?) excepting when one got rear-ended at some traffic lights. Programming the destination into the Prius using an iphone is probably possible but not without access to the phone to install the software. The car would also need to be heavily modified at great expense.
Wow. My drunk copy cat post turned into a real thread.
Love the SDMB!
The way I see most Prius bahaving on the road they may as well be driverless.
This one ran out of gas. Closed.
samclem Moderator