US promotes fiber-optic sensing to boost railroad safety

08 Aug 2018

Department of Transport recommends using methods for safety and efficient operations; report endorsed by US Fiber Optic Sensing Association.

Fiber Optic Acoustic Detection (FOAD) is an emerging technology with the potential to enhance safety in the railroad industry by continuously monitoring the condition of rail, track and rolling stock. A FOAD system pulses laser light down a fiber optic cable buried near a railroad track and, using Rayleigh backscatter, can detect acoustic and seismic signals produced by such events as train movement, rail breaks, wheel impacts, and dragging equipment.

A newly-published two-year study into the potential benefits of FOAD, performed by the Transportation Technology Center entitled Fiber Optic Availability and Opportunity Analysis for North American Railroads identified multiple “priority applications” for its deployment as: broken rail detection, train tracking, monitoring equipment health and track integrity, as well as security and detection of environmental hazards.

The US Fiber Optic Sensing Association (FOSA) applauded the results of the study, which also concluded that there is significant potential for cost savings for the US railroads,” especially if fiber optic acoustical detection technology is used for multiple applications”.

FOSA Director Mark Uncapher commented, “The findings of this Federal government study confirm that fiber optic sensing can make significant cost-effective contributions to enhancing rail safety. The conclusions offer an authoritative validation of the business case for fiber optic sensing for railroads.”

George Palmer, Head of Innovation at Fotech Solutions, added, “These results underscore the cost-effective contributions that new technologies, such as fiber optic sensing, can make to make to improving railroad safety.“

“In addition to its general findings, the study contains specific data quantifying the potential savings to railroads resulting from fiber optic sensing, as compared to alternative technology approaches,” said John Williams, Regional Director for OptaSense in Houston, TX, and Vice-Chairman of the Fiber Optic Sensing Association.

About the report

The objective of this research project was to determine the viability and applicability of implementing FOAD technology in the North American railroad environment. To accomplish this objective, TTCI worked with the newly-formed FOAD task force, comprising representatives from all North American Class I railroads, National Railroad Passenger Corporation (Amtrak), AAR, FRA, and several FOAD technology suppliers.

As interest in this technology has grown, the railroad industry has recognized that FOAD has many potential uses in the railroad environment, and a single FOAD system could potentially perform multiple functions. As a result, an AAR Task Force was formed in 2016 to identify and prioritize the most important applications of FOAD in the rail industry for further research and development.

FOAD suppliers were surveyed for the cost driver information associated with their systems; the North American railroads were surveyed for the cost driver information associated with existing wayside systems used to detect flat wheels, Wheel Impact Load Detectors (WILD), broken rails, and track circuits.

This project performed a high-level analysis of cost drivers and system functionality that compared drivers associated with FOAD technology to drivers associated with current wayside systems used to detect broken rails and flat wheels. The cost analysis also indicates that railroads that use FOAD for more than one application may benefit from potential savings, and those savings would be even greater if existing fiber optic cable can be used for FOAD.

For sections of track where existing fiber optic cable can be used, the estimated costs will be from 62 percent to 72 percent less with FOAD than the combined costs of WILD and track circuits. For sections of track where existing fiber optic cable cannot be used, the percent difference in costs ranges from 3 percent to 28 percent less costs using FOAD than the combined WILD and track circuit costs.

Currently, FOAD technology cannot fully replace the functionality of other systems, particularly track circuits. For FOAD to supplement or replace existing systems, additional development may be needed, or FOAD may need to be combined with other technologies to provide future functionalities.