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Tesla on Autopilot Smashes Straight Through Garage Door, Driver Says
(autos.yahoo.com)
This is a most excellent place for technology news and articles.
Yes, radar was found to be useless at highway speeds for stationary objects because if it responded to such events, you get sudden, emergency "ghost braking." Radar is so low resolution, it cannot tell the difference between the back of a tractor trailer and a large sign or overpass.