Ziwen Wan, a Ph.D. candidate in computer science at University of California, Irvine, has studied why driverless cars may be acting this way.  Wan found that ordinary objects on the road can lead to dangerous driving behavior. … “The software can make the autonomous vehicle behave as conservatively as possible because a safety violation would be very serious,” Wan says. “But this may lead to concerns on the other side, like in some cases, even though it’s safe it will fail to drive normally.” That abnormal driving includes abrupt halts, swerves, erratic behavior or just stopping in the middle of the road.

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