I know a friend of mine was working on a similar technology for Daimler Benz over 15 years ago. Considering that technology still hasn’t advanced shows how hard this much be to implement. From what I remember what he said was the hardest part is to “read the road”. Stretches where all the street signs are in the proper places and markings on the road are relatively simple to navigate, but what happens when you enter a construction zone or go off-the-beaten path?