Toyota fist produced it as an option in the 2003 Prius, there were some earlier types but they were experimental and not for commercial use. By 2012 Ford. BMW and Lexus have their own versions along with Ford’s various divisions like Lincoln. It uses various sensors usually radar pings or lasers distance measurement tools to determine available space. The math to chose a path is nonholonomic, meaning the number of coordinates that represent position and orientation are more than the actual number of control commands.