[a_t48]

How can a combination of existing maps/car technology and LIDAR pinpoint at high resolution where a car is? Imagine a scenario where a car needs to merge across two lanes of traffic and turn into an alley. The car has to be able to plan the merges before it gets to the alley, and know that it is at the proper place to turn. Before you say "GPS" think of how often your phone's GPS messes up.

[badestrand]

Google Maps tells me a few hundred meters in advance so the car AI can know, too. The location does not need to be precise down to a centimeter, it should be enough to know "the alley is somewhat near" so it can start to get into the rightmost lane. Just as we humans do it. There are enough artifical obstacles on the road anyway (wrongly parked cars etc).