In China, engineers have deployed "Autonomous Rail Rapid Transit" (ART) systems that navigate urban streets by following virtual tracks marked with painted dotted lines. These futuristic vehicles use a combination of LiDAR, high-speed sensors, and AI vision systems to "read" the road and maintain precise lane alignment without physical steel rails. The economic advantage is significant; installing these smart trains costs approximately one-fifth of the price of a traditional tram system. By elim