Autonomous Rail Rapid Transit (ART) is a lidar guided articulated bus system for urban passenger transport. Developed and manufactured by CRRC through CRRC Zhuzhou Institute Co Ltd, it was unveiled in Zhuzhou in the Hunan province on June 2, 2017. ART is specifically referred to as a train or rapid transit by its manufacturer, however the public describes it as a bus. Its exterior is composed of individual fixed sections joined by articulated gangways, resembling a rubber-tyred tram.

A bi-articulated bus or double-articulated bus and sometimes train-bus, tram-bus, trackless tram or double bendy bus is a type of high-capacity articulated bus with an extra axle and a second articulation joint, as well as extended length. Bi-articulated buses tend to be employed in high-frequency core routes or bus rapid transit schemes rather than in conventional bus routes.