Autonomous Rail Rapid Transit
Autonomous Rail Rapid Transit (ART) is a lidar (light detection and ranging) 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.
The system is labelled as "autonomous" in English, however, the models in operation are optically guided and feature a driver on board.
Automated Rapid Transit systems (ARTs) can operate independently without the need for a guiding sensor and as a result, they fall under the classification of buses. Consequently, vehicles deployed on these routes are mandated to display license plates.
Background
Before the announcement by CRRC, optical guided buses have been in use in a number of cities in Europe and North America, including in Rouen as part of Transport Est-Ouest Rouennais, in Las Vegas as a segment of Metropolitan Area Express BRT service (now discontinued), and in Castellón de la Plana as Line 1 in TRAM de Castellón network
Description
An ART vehicle with three carriages is approximately 30 m (98 ft 5 in) long.
The 6.5 km (4.0 miles) long ART lane was built through downtown Zhuzhou and inaugurated in 2018.
Sensors and batteries
The ART is equipped with various optical and other types of sensors to allow the vehicle to automatically follow a route defined by a virtual track of markings on the roadway.
The ART is powered by lithium–titanate batteries and can travel a distance of 40 km (25 miles) per full charge. The batteries can be recharged via current collectors at stations.
Benefits and limitations
A 2018 article by a sustainability academic argued trackless trams could replace both light-rail and bus rapid transit due to low cost, quick installation and low emissions.
Proponents have argued the lack of rails means cheaper construction costs.
However, because the ART is a guided system, ruts and depressions could be worn into the road by the alignment of the large number of wheels, so reinforcement of the roadway to prevent those problems may be as disruptive as the installation of rails in a light rail system. Researchers in 2021 found evidence of significant road wear due to trackless tram vehicles, which undermined claims of quick construction, with the researchers finding significant road strengthening was required by the technology.
A few abandoned proposals for light-rail lines have been revived as ART proposals because of the lower projected costs. However, a different report, by the Australian Railways Association, which supports light rail, said there were reliability questions with ART installations, implying the initial suggested capital cost savings were illusory.
The Government of New South Wales considered the system as an alternative to light rail for a line to connect Sydney Olympic Park to Parramatta. However, concerns were raised that there was only one supplier of the technology,
The Auckland Light Rail Group, in its studies of trackless trams for the City Centre to Mangere line, found that trackless trams would have a lower capacity than claimed. The official specifications for the ARRT assume a standing density of eight passengers per square meter, whereas many transit systems have more typical standing densities of four passengers per square meter. Based on that, the 32-metre (105 ft 0 in) long ARRT would more realistically have a capacity of 170 passengers, rather than the claimed 307.