In an era of growing rail traffic and increased interest in high-speed rail passenger service, several ongoing projects suggest the importance of information technologies (IT) for railroad safety. IT is at the heart of many train control concepts, aimed at reducing the probability of collisions between trains while increasing track capacity and asset use. At least 13 projects are at various stages of implementation in the United States and Canada, a few of which are described below.
The states of Oregon and Washington, in partnership with the Federal Railroad Administration (FRA) and Burlington Northern Santa Fe and Union Pacific railroads, are testing new Positive Train Separation technology. The system, which uses global positioning satellites and land-based transponders, is being tested for reliability and the ability to safely provide more capacity on the existing rail infrastructure. When operational, the system may enable passenger trains to operate faster than the current 79 mph speed limit. A communications system being developed as part of the project would carry control signals between trains and railroad dispatch centers. Testing of the prototype has verified the reliability of digital communications links, automatic location systems based on the Differential Global Positioning System (DGPS), and the performance of an adaptive braking system governed by an onboard computer to determine safe braking distances.
Michigans Department of Transportation (MDOT) is installing and demonstrating an advanced communications-based train control system on an 80-mile segment of the Amtrak-owned portion of the Detroit-Chicago corridor between Kalamazoo, Michigan, and the Indiana state line. MDOT and Amtrak matched the federal funds to upgrade the track so that trains can operate at speeds of up to 110 mph and to make fencing and station improvements. As a first step, a 100 mph test of an Incremental Train Control System (ITCS) was conducted on a 20-mile section. Revenue service could begin in 2000, and will be coordinated with local freight operations on the line.
The ITCS uses digital radio to broadcast status information to the train. An onboard computer combines information from the DGPS, wayside status information, and data from an onboard route database to inform the engineer of safe operating speeds. The onboard computer acts to stop the train if unsafe operation is attempted. The onboard computer also uses the digital radio links to activate highway grade-crossing warning systems at the appropriate time for the approach of the high-speed train, and confirms the readiness of the crossing systems back to the train.
In a portion of the Chicago-St. Louis corridor, the state of Illinois, FRA, and major freight railroads represented by the Association of American Railroads are conducting a joint demonstration of a Positive Train Control system expected to cost about $60 million over four years. The program will address interoperability issues among the various railroads, as well as result in a demonstration system. The demonstration system will use DGPS onboard locomotives, digital radio, and advanced computers to monitor the location of trains in the rail system and oversee operation by locomotive engineers to prevent collisions and overspeed derailments. The system on the Chicago-St. Louis corridor will be controlled from Union Pacifics Harriman Dispatch Center in Omaha.