[Fricken]

Imagine an uncontrolled intersection. The Robotaxi is approaching from one direction. In the opposite direction is a cyclist who intends to turn left across the Robotaxi. There is also a pedestrian that may or may not cross the street, and another vehicle about to cross in front of the Robotaxi from the other direction. There are a huge number of ways this scenario can play out, and any decision made by one agent can affect the behaviors of all the others, compounding it's complexity. Humans can game out these situations intuitively, but current AI cannot read deep enough into the matrix to deal with these situations quickly and reliably.

[TheSmiddy]

In Australia there are no uncontrolled intersections (that I am aware of). Every single junction clearly marks who must give way and we don't have any 4-way stops, instead using roundabouts in these situations.

It's possible that for self driving to work road systems will have to be more formalised to remove the ambiguous situations you've described. I can't imagine it working well in China or Indonesia where traffic flows much more like water in a stream and lanes are merely just suggestions.

[taneq]

There are definitely uncontrolled intersections once you get out of the cities. My understanding is that if unmarked, there’s an implied give-way at the side road in a T-junction and all roads in a four-way junction.

[fratlas]

I imagine self driving cars won't be outside of cities for years and years.

[ghaff]

Outside of cities on limited access highways seem like the much easier situation--and, frankly, a pretty significant win for both comfort and safety once people give up their dream of having a personal chauffeur for their entire lives. It's self-driving in e.g. Manhattan or Boston that I can't really begin to imagine in less than decades.

[l33tman]

Also people regularly just ignore the lane markings (and break all the other rules too...). You have to consider all those cases as well.

[nradov]

What is progress like on dealing with hand signals (or other gestures) from law enforcement or construction workers directing traffic?

[BubRoss]

There are rules to that situation. You can start there, let other cars go ahead of you if they break the rules, go slow and not hit anything. It isn't as if self driving cars can't look to the side or stop if something changes. Beyond that Jim Keller would say that not getting hit by something else is a matter of ballistics.