L.B. Foster's Insight Rockfall Monitoring System Installed for Canadian National Railways

L.B. Foster’s Insight Rockfall Monitoring is a revolutionary system that actively monitors the right of way and protects rolling stock in rockfall prone areas. The safety critical system comprises multiple light detection and ranging units known as LiDAR. If a rock of sufficient size to pose a threat to a train is detected on the track, LiDAR technology remotely alerts controllers about the size and location of the obstruction without an engineer ever needing to visit site and repair a wire detector.

Insight Rockfall Monitoring also includes cameras on every other LiDAR unit that will automatically take a picture and send an email when the alarm is triggered. This allows the engineers to see an obstacle in real time and appropriately respond to alarms. The LiDARs are also equipped with motorized shutters that will close and open to protect the LiDAR from debris when a train passes.

L.B. Foster installed the system in a side-by-side trial with the existing slide fences that are currently in place on the CN. Over the course of one week, 23 LiDAR units were installed on a section of four different tracks separated by three tunnels and will cover an overall distance of 1,100 feet.

Currently, CN utilizes slide fences for rockfall protection which are a series of wires that run along the tracks. If a wire breaks, the loss of current through the wire activates a stoplight and alarm to alert the oncoming trains that something may have fallen onto the track. With the slide fences in place, false positive alarms are triggered 99.5% of the time. These false alarms can be generated by anything that breaks the slide fence such as an animal, small rock, or ice.

The false alarms signaled by the slide fences cause operational delays and problems that require attention from engineers to clear the alarm. The installation of Insight Rockfall Monitoring will reduce the number of false positive alarms that are triggered on CN tracks using its LiDAR system to optimize detection of hazardous obstacles and the journey of trains through rockfall prone territories. The LiDAR units are also able to distinguish between moving objects, such as animals and the actual threats, which are rockfall and landslides.

During the winter months, this area sees thousands of alarms along the slide fence network. Each time the alarm is activated, this high tonnage track is forced to delay the freight which is a costly and time-consuming effort.

Will Becker, Technical Sales Engineer at L.B. Foster, explained, “The way the system works is that we are scanning along a 100-foot monitoring plane. Each LiDAR scans 50% of the area that the adjacent LiDAR is scanning, which creates a redundant overlap in our scan fields. When an obstacle is detected, only one out of two LiDARs will need to detect it to generate an alarm."

Michael O’Connell, Manager of Product and Business Development at L.B. Foster, commented, “Our focus for the Canadian National Railway specifically was to provide a safety critical product that replaces slide fences and gives them the ability to reduce and eliminate interruptions and delays due to slide fence false alarms.”

Becker added, “This technology is being deployed to more reliably detect rocks and increase train speed through rockfall corridors.”

Not only is this technology more dependable than slide fences, but it also requires much less maintenance. The only maintenance required is a simple LiDAR lens cleaning with water on a microfiber towel every 6-12 months.

L.B. Foster is excited to observe Insight Rockfall Monitoring, and how we can improve the detection of rockfall hazards in our partnership with Canadian National Railways.