UAV Applications Takeoff

Unmanned Aerial Vehicles (UAVs) have numerous applications for the rail industry, ranging from track inspections and aerial mapping to detecting trespassers and creating a safer right-of-way. But a successful application requires sound engineering, sound planning and a working knowledge of rules and regulations from multiple federal agencies, including the Federal Railroad Administration (FRA) and Federal Aviation Administration (FAA).  

With this in mind, private firms such as 360 Rail Services and Zephyr Rail and regulators, such as FRA, have worked to ensure UAVs fit into solutions that not only gather needed information but ensure safe operation – because it’s more than just flying a drone in the air.

UAV applications provide in-depth datasets to help with maintenance

When it comes to track inspections, 360 Rail Services starts off with understanding what the client needs and where the latest inspections have taken place. From there, the company obtains authority from the necessary supervisors and operational entities and then facilitates a safety debrief meeting – all before the UAV is granted liftoff.

“It’s not something where we just throw a drone up in the air and get going,” explained Peyton McCain, marketing manager, 360 Rail Services. “There’s a lot of planning that goes into it initially to ensure there’s the maximum amount of safety possible.”

Once the safety and planning procedures are put in place, the company sends the UAV into the air and flies it over the center line, which can be done on any given track and can be used on traditional main line track or in a yard where there are multiple tracks running alongside one another. As the drone flies over the tracks, it collects high resolution imagery, as well as “highly accurate GPS information and highly accurate altitude information,” McCain explains.

“This gives us a data set we can feed into an artificial intelligence that we have developed alongside Adrenna, our software partner in this program, that will go through and identify a wide range of track defects,” McCain said. “For example, because we can so accurately calculate the position in altitude, we can provide gage within an accuracy of less than one inch.”

Instead of solely relying on a human to walk the track for inspections, an artificial intelligence grading UAV-collected data automates this process with machine analysis and acts as a supplemental tool to help mitigate human error. In addition to gage, the UAV can also capture a range of track defects such as tie grading; the presence of or lack of fasteners; if tie plates are cutting in; and track geometry. The company is currently working on using UAVs to assess switch points.

For the artificial intelligence to complete a track assessment, it needs accurate data and high-resolution images. This required 360 Rail Services to use a custom payload – a combination of a computer, an altimeter and a camera – built by Adrenna to be attached to the drone. The altimeter talks to the camera, that then talks to the computer integrated into the payload, which ultimately talks to the drone and is how the data is captured while the UAV is in flight. The data is then uploaded to the cloud-based artificial intelligence program for assessment.

The artificial intelligence program can accurately pinpoint defects because it was trained over thousands of pictures across hundreds of miles of track, McCain explains. The program was then trained to recognize what would be considered a defect, such as broken ties, cracked joint bars, wide gage, etc.

“That way we can really be confident in looking at [the data] and having it say this is a defect, this is not a defect,” McCain said. “We’ve done a significant number of ground walkthroughs to go back and say, yeah there’s not a false positive, there’s not a false negative.”

Once the dataset has been compiled, there’s a way to screen by defect and by track classification, explains Larry Stockton, CEO 360 Rail Services.

“We’re able to filter out some of those defects that may be applicable to a Class 5 track but not applicable to a Class 1 track,” Stockton said.

Once the dataset has been compiled according to the clients’ needs, 360 Rail Services sends the client a digital folder they log into where they can see a list of the defects. McCain notes this includes a map of the photo so the clients can easily locate defects. Instead of having someone manually scan the tracks, they can send someone to the exact coordinates of where the defect can be found, while also already knowing what the nature of the defect is.

“The intention is in the future to provide a customer portal that will allow them to look at current inspection and past inspection for their specific tracks, and be able to relate that to where problems are starting to come up,” Stockton said.

Consider regulations and the applications – is a UAV really the best solution?

Marc A. Cañas, vice president and a founder of Zephyr Rail, agrees it’s more than flying a drone in the air to capture data, noting there are multi-levels and multilayers at play with technology and regulation that need to come together in order to get a usable and accurate end product.

“It takes a lot of sound engineering and judgement and our years of railroad engineering experience, where we take the information and see if the application of the drone is correct or not,” Cañas said.

Zephyr Rail was established in 2015 as a spinoff of the company JL Patterson, which sold in 2015 to a multi-national firm. However, the purchasing firm wasn’t interested in the UAV component of the business, so Zephyr Rail was born and now provides engineering and construction management services. The company first started working with UAVs in 2013 to solve a workflow problem, Cañas says. Specifically, when it came to mapping, the company needed a solution that provided more control, higher resolution and closer-up details for a project it was working on at the time.

“As soon as everybody understands what we can do with drones, they become an [important] piece for workflow in not only engineering but also in workflow for construction management,” Cañas said. “So, we rolled them into our regular project cycles and we use them to enhance either design or inspection or construction management. It’s really another tool in our toolbelt.”

While UAVs are a great tool, it’s important to understand when it’s an appropriate application. This usually comes down more to regulations than the technology being able to perform the task, such as restrictions on where people can fly UAVs. For instance, operating a UAV in a controlled airspace, such as an active airport, wouldn’t be the best solution due to FAA regulations.

“That is not a good spot for a drone because the logistics of being able to get permission to fly in close proximity to an airport because of the controlled airspace issue makes the tool unusable,” Cañas said.

Another thing to consider is the time of day when the UAV will be used. When performing mapping or inspection services, the UAV needs to capture video or photos, which requires light. If flying at night, not only is there a lack of light to capture quality images and videos but the FAA also requires a waiver to fly at night. Even if the technology is applicable, it comes down to regulations when considering if a UAV is the correct solution.

“Usable is not always the only litmus test; you have to go beyond that,” Cañas said. “You have to have a working knowledge of what the rail operation requires versus what the air operation requires and how you meld those two together using sound engineering and construction management and inspection experience to bring that together. And then come up with a deliverable with what the client is really needing.”

UAVs bring an added level of safety at FRA

Construction management and engineering projects aren’t the only applications for UAVs. FRA is testing UAV applications concerning safety, such as evaluating UAVs’ effectiveness in detecting trespassers along the railroad right-of-way and creating accurate grade-crossing profile data.

FRA worked to determine the effectiveness of using UAVs to detect trespassers along the right-of-way in partnership with the Brunswick, Maine, Police Department (BPD), explains Francesco Bedini-Jacobini, general engineer, Train Control and Communications Research Division, noting the results from this project will be published in an upcoming technical report. FRA is also funding Michigan Technological University’s (MTU) study using UAVs with artificial intelligence and machine learning techniques to provide real-time detection of railroad trespassers.

“In the BPD project, a UAV was flown at certain times of the day and the camera mounted on the vehicle would transmit video to the operator, who in turn would take the appropriate action,” Bedini-Jacobini said. “In ongoing research, FRA is looking into developing an autonomous method of warning the appropriate authorities of a trespass event as it occurs on a right-of-way. These objectives are part of the research project with MTU.”

In another study, FRA explored the use of UAVs to produce accurate grade-crossing profile data. The results were promising, proving that the photogrammetry method produces acceptable results while being more cost effective than the light detection and ranging (LiDAR) method, says Cameron Stuart, general engineer, Track Research Division. Currently, there are two projects exploring how UAVs detect and measure humped grade-crossing conditions while detecting and locating signage and other appliances related to the grade crossing area, Stuart adds.

“Eventually we would like to mature this technology to the point where it can supplement the LiDAR system currently deployed on track-bound vehicles,” Stuart said. “Ideally, the UAV-based technology would be adopted by railroads and state departments of transportation to increase the efficiency of grade crossing inspection operations.”

While this application is still being tested, the current projects are progressing successfully, notes Stuart.

UAVs and the benefits they provide

Whether it’s executing a track inspection, creating an aerial mapping or detecting trespassers along the right-of-way, UAVs provide useful benefits.

For example, during track inspections or construction projects, UAVs can pull people off the track and minimize exposure to possible safety incidents. And UAVs allow service to continue as normal.

“The good thing about this is it allows operations to continue while a track inspection is taking place, so there’s no shut down [and] no stoppage in trains themselves,” Stockton said. “They can continue on their routes while the inspection is taking place.”

For mapping project, UAVs can offer a more cost effective-solution and provide a quicker project turnaround. Before Zephyr Rail utilized UAVs for a mapping project, it would take the company between six to eight weeks to collect a one-mile project map, says Cañas. Now that window has shrunk to three days.

“I can be onsite at eight or nine in the morning; I can fly a mile in about 25-30 minutes and get all the data that I need, and have your results and models in the next day, possibly if it’s a really complex model then maybe the second day,” Cañas said.

But while the technology is there and the benefits are proven, regulations still need to be considered, especially because technology is outpacing regulation, explains Cañas.

“Regulation is trying to catch up, but as soon as it [does], the technology is already advancing beyond that, so it’s going to be a never-ending race,” Cañas said. “We need something to keep going forward, otherwise that technology is going to die off or it's going to be over regulated. It's up to us who are in this industry to work with the regulators as much as we can to come up with a middle ground that is going to work.”