In the part of the Phoenix area where I live, three various companies have been testing self driving cars for about two years .
On my way home from work today, I was behind one from WAYMO, the division of Google .
The vehicle now used, is a Fiat / Chrysler Pacifica, large van .
Most of the exterior sensors are hidden behind fairings, so it doesn't stick out in traffic as much as the Lexus RX350's did with all their sensors exposed .
I was on a low speed, 30 mph street going through residential neighborhoods .
There was construction on this street, replacing concrete curbs that had buckled due to the heat here .
This street is one lane both directions with a center turn lane .
When you came up one a construction area on your side of the street, there were cones and signs directing traffic into the center turn lane .
This self driving car did not know what to do when it came up on this, it turned left, then right, then came to a stop, had the look that it was confused .
Driver was doing something in the vehicle with the controls .
Finally after 30 seconds the vehicle started moving this happened at each lane change with the cones and signs .
Got onto a major surface street, speed limit 45 mph .
A pick up truck about 150 yards/ meters pulled out from a side street and merged into the opposite direction traffic .
This self driving vehicle braked heavily and slowed to around 20 mph, even though the truck was travelling quickly no where near a threat of a collision .
Looks like there is still a lot of work to go before this will become mainstream .
I have seen three different company vehicles in my neighborhood, WAYMO, Intel and Uber .
Next time I'm next to one, I'm going to mess with it and see what it does !!!

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As of 28 August 2014, according to Computer World Google's self-driving cars were in fact unable to use about 99% of US roads.[57] As of the same date, the latest prototype had not been tested in heavy rain or snow due to safety concerns.[58] Because the cars rely primarily on pre-programmed route data, they do not obey temporary traffic lights and, in some situations, revert to a slower "extra cautious" mode in complex unmapped intersections. The vehicle has difficulty identifying when objects, such as trash and light debris, are harmless, causing the vehicle to veer unnecessarily. Additionally, the lidar technology cannot spot some potholes or discern when humans, such as a police officer, are signaling the car to stop.[59] Google projects plan on having these issues fixed by 2020