[jrd259]

The other issue is that it requires the driver to read a screen while driving. in 1988 at the MIT Media Lab I built a system called Back Seat Driver that provides spoken driving directions, allowing the driver to keep their visual attention on the road. https://www.youtube.com/watch?v=8C0V6lDKQ0Y&t=21s. It ran on a Lisp Machine, not in the vehicle. A later version ran on a Sun computer in the trunk.

The in-car nav system was also augmented dead-reckoning, like Etak. GPS was still denied to civilians at the time.