[wool_gather]

There's an opportunity for them to communicate better with pedestrians than the average human driver. Drivers tend to assume that their intent to stop or not to stop is obvious and don't bother with a clear signal like flashing their lights or waving visibly.

From the pedestrian's perspective, it can be hard to see the driver at all (small movements of the hand can be invisible in sun glare; direction of gaze likewise), and also hard to tell what they're doing. Just because they're slowing somewhat as they approach doesn't mean they see you or intend to stop.

[throwaway201103]

One could imagine a standardized set of signals on the front of the car. Red = stopped/stopping. Yellow = about to start moving; Green = moving and continuing. Something like that.