Real-world traffic produces more distinct scenarios than any team can pre-determine, making correct behavior in unpredictable situations the open problem of self-driving.

A vehicle travelling at 40 miles per hour covers about 60 feet every second. Within that second, software has to determine what is physically nearby, classify each object, estimate where those objects will move, select a path, and issue steering and braking commands. Doing all of this quickly is something that has been largely solved. However, doing this correctly in unpredictable and distinct traffic situations is still an open problem. This is because real-world traffic produces more distinct scenarios than any team can pre-determine. For example, Waymo describes one such case, where a vehicle is on fire on the road ahead while the drivable lanes remain physically clear. The geometry of such a scenario might permit driving straight through it. However, the real meaning of it calls for turning around or taking preventive action.

Read full article ↗excerpt · fair-use quotation