It can spot a potential problem 500 feet away and tell the difference between a red and green light. It can anticipate a corner even before the driver turns the steering wheel. It’s designed to prevent a crash but can also make it easier to survive a collision even as it automatically calls for help. Toyota’s Lexus luxury brand is giving the public a first look at its advanced active safety research vehicle this week. Also known as the AASRV, it is designed to test and demonstrate a variety of automated vehicle safety technologies that could be used in production vehicles in the not-too-distant future, according to Toyota officials.