Weather Information and

Intelligent Railroad Systems

Steven R. Ditmeyer

Director, Office of Research and Development

Federal Railroad Administration

FRA - AAR - NCAR Symposium on

Enhanced Weather Information for

Improved Railroad Safety and Productivity

Boulder, Colorado

October 17-18, 2001

Secretary of Transportation Norman Mineta has spoken often about the need for all modes of transportation to make use of “intelligent systems,” that is, sensors, computers, and digital communications, to collect, process, and disseminate information to improve transportation safety, security, capacity, and operational effectiveness. Intelligent Transportation Systems (ITS) for highways and mass transit are based on these technologies, as are the new air traffic control and maritime vessel tracking systems. The military services, the major parcel delivery companies, pipeline operators, and police, fire, and ambulance services also use these technologies.

The Federal Railroad Administration and the railroad industry are working on the development of Intelligent Railroad Systems that would incorporate the new sensor, computer, and digital communications technologies into train control, braking systems, grade crossings, and defect detection, and into planning and scheduling systems as well. The FRA believes that these technologies will prevent collisions and overspeed accidents, provide greater security, increase railroad capacity and asset utilization, improve service to railroad customers, improve railroad energy efficiency and emissions, enable railroads to measure and manage costs, and increase railroad economic viability and profits.

The systems can be implemented as independent systems, in which case their benefits will be limited, or they can be implemented as integrated systems, in which case the benefits will be compounded. FRA urges the railroad industry to adopt an integrated approach when implementing these systems.

Following is a description of some of the technologies, programs, and systems that have been developed or are under development:

Digital data link communications networks provide the means for moving information to and from trains, maintenance-of-way equipment, switches and wayside detectors, control centers, yards, intermodal terminals, passenger stations, maintenance facilities, operating data systems, and customers. Data link communications will replace or supplement many of today’s routine voice communications with non-voice digital messages and will effectively increase the capacity of available communications circuits and frequencies.

The Nationwide Differential Global Positioning System (NDGPS), an augmentation of the GPS, provides one-to-two meter positioning accuracy to receivers. NDGPS receivers will be placed on locomotives and maintenance-of-way vehicles, and their locations will be transmitted back to control centers over a digital data link communications network. NDGPS is now operational with single-station coverage over 80 percent of the continental US, and complete dual-station coverage is expected in 2004. The National Oceanic and Atmospheric Administration uses the data from NDGPS sites to determine the amount of precipitable water vapor in the atmosphere.

Positive Train Control (PTC) systems are integrated command, control, communications, and information systems for controlling train movements with safety, precision, and efficiency. PTC systems bring together digital communications networks, continuous and accurate positioning systems such as DGPS, on-board computers on locomotives and maintenance-of-way equipments, in-cab displays, throttle-brake interfaces on locomotives, wayside interface units at switches and wayside detectors, and control center computers and displays. PTC systems will improve rail safety by significantly reducing the probability of collisions between trains, casualties to roadway workers, damage to equipment, and overspeed accidents.

Electronically-controlled pneumatic (ECP) brakes use an electronic signal along an on-train communications network to initiate brake applications and releases and, thereby, permit the simultaneous application of all brakes on a train, substantially shortening braking distance. They are an advance over current train braking systems that use air to both power the brakes and initiate brake applications and releases. As with PTC, this technology already exists, but is not yet widely deployed.

Automatic Equipment Identification tags have been installed on all U.S. and Canadian freight cars and locomotives since 1995. Electronically reading these tags, and combining it with information from NDGPS receivers on locomotives, enables railroads to know the precise location of every locomotive, car, shipment, and train crew member at all times.

Wayside equipment sensors can identify defects that can occur on passing trains so they can be stopped for necessary repairs. Among the defects that can be detected by wayside sensors are overheated bearings and wheels, deteriorating bearings, cracked wheels, derailed wheels, and excessively high and wide loads.

Locomotive health monitoring systems consist of sensors mounted on locomotive engines; electrical, air, and exhaust systems, and fuel tanks. These sensors communicate over the digital data link network to permit real-time monitoring of locomotive performance at control centers and maintenance facilities.

Car onboard commodity and component sensors can monitor the status of the commodities being carried and identify a number of car defects. This information can be transmitted over the ECP brake communications channel and digital data link to train crews, control centers, and maintenance facilities.

Intelligent grade crossings use information gleaned from PTC systems to provide information on train presence and arrival times to motorists and information on a vehicle stalled in the middle of a grade crossing to railroad control centers. This information could dramatically reduce grade crossing accidents nationwide.

Tactical traffic planners produce plans showing when trains should arrive at each point on a rail line, where they should meet and pass, and which trains should take sidings. These plans complement the activities of PTC systems.

Strategic traffic planners serve as the highest-level real-time control system in the PTC control hierarchy, analyzing schedule and performance data to maximize safety and efficiency.

Freight car reservation and scheduling systems allow customers to reserve freight car capacity and routing, allowing railroads to better schedule their cars. These systems, similar to airline reservation systems, reduce shipping of empty cars, and reduce delays to loads and empties at intermediate yards. They also reduce fleet size requirements and improve asset utilization.

Last, but not least, in this listing of major Intelligent Railroad Systems are intelligent weather systems that consist of networks of local weather sensors and instrumentation - both wayside and on-board locomotives - combined with national, regional, and local forecast data. They will alert train control centers, train crews, and maintenance crews of actual or potential hazardous weather conditions. Intelligent weather systems will provide advance warning of weather-caused hazards such as flooding; track washouts; snow, mud, or rock slides; high winds; fog; high track-buckling risk; or other conditions which require adjustment to train operations or action by maintenance personnel. Weather data collected on the railroad will also be forwarded to weather forecasting centers to augment their other data sources. The installation of the digital data link communications network is a prerequisite for this activity.

Other systems that enhance or contribute to Intelligent Railroad Systems are:

· Knowledge display interfaces

· Crew registration and time-keeping systems

· Crew alertness monitoring systems

· Track forces terminals

· Wayside and vehicle-borne track sensors

· Energy management systems

· Work order reporting systems

· Train, locomotive, and crew scheduling systems

· Travelers advisory systems

· Yield management systems

In order to show how all of the previous systems and initiatives fit together, and to help identify the key interfaces for standardization, an architecture for Intelligent Railroad Systems is being developed. A first step in this direction is shown in the following figure, which is a top-level interconnect diagram that identifies the key elements of Intelligent Railroad Systems and the communications link interfaces between them. It is based on conventions developed by the Architecture Development Team for the National ITS Architecture. This type of diagram is known as a “sausage diagram” in which the “sausages” represent the various types of communications links that move information between vehicles, fixed installations along the transportation right-of-way, control and management centers, and customers.