U.S. passenger and freight railroads are fielding GPS-based Positive Train Control (PTC) systems. PTC refers to communication-based/processor-based train control technology designed to prevent train-to-train collisions, over speed derailments, incursions into established work zone limits, and the movement of a train through a main line switch in the improper position.
PTC systems vary widely in complexity and sophistication based on the level of automation and functionality being implemented, the system architecture used including wayside systems (e.g., non-signaled, block signal, cab signal, etc.), and the degree of train control. This advanced safety technology, required by federal law, will be operational on over 60,000 miles of the national rail system in the 2018 to 2020 timeframe.
Beyond PTC, GPS-based technology gives dispatchers and passengers accurate information on train location and station arrival times. It enables the automation of track surveying, mapping and inspection systems that work much faster and more accurately than non-GPS based systems, saving time and money while improving safety.