The Electric Power Research Institute (EPRI) worked with manufacturer RADeCO and Exyn Technologies, a developer of aerial robot systems, to demonstrate an autonomous drone at Exelon’s Peach Bottom nuclear power station in Pennsylvania.

The drone was used to inspect components in elevated hard-to-access areas, search for temperature anomalies, and collect dose rate surveys in radiological zones — without operator intervention (ie operated autonomously).

Brandon Di Zebba, senior radiological engineer at Peach Bottom, says Exelon should see improved industrial and radiological safety through using this autonomous technology.

“What has impressed me with this technology is that it is all automated,” Di Zebba said during an EPRI video about the project. “Previous technology has required the pilot to have line-of-site of the drone… which is not always possible in the nuclear industry.”

RADeCO was EPRI’s main subcontractor for the project.

“Our focus was to demonstrate an autonomous aerial system and a ground system,” explains Keith Lovendale, president and CEO RADeCO. RADeCO teamed with Exyn Technologies, which supported navigation system design and operation.

Raghu Balasa, head of strategy at Exyn says the drone, which was equipped with a camera for visual inspections, temperature sensors and a dosimeter, was programmed for autonomous flight using a simple tablet interface.

First, the vehicle mapped the indoor area using a Lidar sensor and inertial units in the robot. Destination points were then plotted on the 3D map created by the drone’s software.

The drone travelled autonomously to the identified component inspection locations; piping where heat blankets were placed and energised; and dose rate measurement points. As the drone moved along prescribed navigation points, the system was able to display and record data such as measured dose rates on the 3D Lidar map in real-time.

A machine-learning algorithm integrated into the system enabled it to identify and avoid obstacles, including unexpected visitors in the room, a key safety feature.

“As far as deploying the technology,” Richard Bolding, senior instrument physicist at Peach Bottom, says it would be straightforward and “something that we must look at if we want to be cost-effective.”

This will be particularly important for Peach Bottom 2&3, which have recently been granted a 20-year licence renewal by the US Nuclear Regulatory Commission (NRC), extending their potential operating life until 2054.

Exelon Nuclear’s chief nuclear officer, Bryan Hanson, said in March that the Peach Bottom plant is “well-suited” to keep running but noted the difficulties of trying to compete with cheaper natural gas in the electricity market.

Exyn says is it still investigating a range of potential applications for autonomous drones in the nuclear industry, and the range of sensors they could deploy. It is also working with industry to transfer the software on to smaller- sized drones, as the current platform is too large to go into many areas that would benefit from autonomous inspection.

EPRI is also further researching uses of autonomous technology in the nuclear power industry including:

  • Smaller drones to allow access into tighter areas of the plant
  • Surface vehicles for the collecting of smears for contamination surveys.
  • Outdoor drones for collecting radiological data to support a plants’ emergency plan.

For more information contact Richard McGrath at EPRI (rmcgrath@epri.com).

A video showing the drone in use is available on EPRI’s YouTube channel https://www.youtube.com/watch?v=97lyDoAOif4