MORE BART HARDWARE

Communications, fares collection, station design and subway construction problems are described for the Bay Area Rapid Transit (BART) system. BART's central-control room at Lake Merritt is the nerve center for its complex communications network, which includes voice, ATC, and digital transmission. More than 300 discrete communication channels are used in the wireline system and four radio channels. The network consists of more than 225 km of wirelines strung along the subway tunnels and transbay tube, in wayside trays along the aerial structures, and buried underground on the right of way at grade level. The wireline cables are all wired-air pressurized to 5 lb//f/in**2. Each circuit is interference-protected from the wayside's electrical environment by standard carbon block and fuse. At BART's facility at Hayward, a computer console directs switching, inventory and communications. By flipping a switch, BART personnel can inform the computer of a desired route to guide a train between storage, repair barn, or mainline tracks. Designed for maximum safety - as well as flexibility - the computer first checks to ensure that the route is unoccupied, then automatically performs the necessary switching and initiates safeguards to keep other trains off the route until it is again clear. The system keeps track of all rolling stock in the yard and displays its location on both the console and a separate monitor. It also governs the facility's entire communications system. The world's first fully automated fare-collection system (AFCS) has been installed throughout the BART system's 34 stations. By means of ACFS, a passenger or commuter may ride the line indefinitely without having to contact a station attendant or any other BART employee. Illustrations of stations, passenger-flow diagrams and a cross-section view of construction at San Francisco's Civic Center station are given. The article concludes with a comparative review of other ″BART-like″ systems, active in Toronto and Montreal, proposed for the metropolitan areas of Atlanta, Ga (MARTA) and Washington, DC (WMATA).