I worked on a driverless backhoe system for John Deere in the early 80's. No GPS then. It was scrapped because we didn't have the technology to make it practical and Liability was also a big issue. What if a kid got in the way? Today vision systems are pretty good but I wonder how long it will take to gain trust.
I rather doubt a system like this will be used without an operator present in the forseeable future.
Reason: Liability and unions.