A San Antonio-based team of researchers and engineers are set to send drones roughly the length of a No. 2 pencil to the site of the damaged former Fukushima Daiichi nuclear power plant. Their mission? To assess conditions in an area too dangerous for humans to enter and too radioactive for even robots to function effectively.
Awarded a contract from Tokyo Electric Power Company Holdings, the Southwest Research Institute (SwRI) has been tasked with developing unmanned aerial systems, or drones, to collect information from the radiation-rife containment vessel, the structure that contains Fukushima’s nuclear reactors damaged in a 9.0-magnitude earthquake in 2011.
The quake and resulting tsunami rocked the northwest coast of Japan, causing three nuclear meltdowns at the Fukushima plant. Radioactivity at the site has thwarted previous efforts to collect information and gauge conditions inside the containment vessel.
Richard and Monica Garcia, who are husband and wife, led a simulated a drone flight at SwRI’s San Antonio campus on Culebra Road, showing how the tiny drones can maneuver through what will be a foggy, pitch-black, and hard-to-navigate containment site.
“This is a formidable challenge,” said Monica Garcia, who is the project manager and a senior research engineer in SwRI’s Intelligent Systems Division. “The conditions inside the containment vessel at Fukushima Daiichi are quite possibly the most challenging environment that the SwRI-Penn team has had to address. We will be pushing the envelope in terms of the technology.”
Underwater and ground-based robots previously have explored the former nuclear plant, but those robots were tethered to the containment vessel, Monica Garcia said.
“Where some of the previous robots’ investigations were on the order of hours or days, this particular system can operate on the order of minutes,” she said. “And it’s extremely beneficial because many internal components of robotic devices end up failing when there’s exposure to high amounts of radiation.”
The trial run for the SwRI’s robotic system involved exposing the devices to the same levels of radiation found inside the Fukushima reactor.
The drones are more mobile, not just because their aerial ability allows them to maneuver in more ways than the ground-based robots, but also because they are so small. Richard Garcia, the project’s technical lead, said the drones measure 15 centimeters from motor to motor.
Most of SwRI’s simulations were conducted on the institute’s campus on Culebra Road, and the team received help from researchers at the University of Pennsylvania who wrote algorithms that will automate the drones’ flight path.
Monica Garcia said although the technology was designed for a very specific purpose, it could have an array of applications in the area of unmanned aerial vehicles.
For example, the drone flight will be conducted largely without wireless communications, the Garcias said, which could prove a useful development for exploring caves and going into disaster areas with unmanned aerial vehicles.
“We can’t guarantee wireless communication inside of that environment,” Richard Garcia said. “It’s a very confined environment with lots of concrete. We expect to lose wireless communication very quickly.”
Now that the team has proven the project’s feasibility, it will meet with the Tokyo company to discuss the next steps. That meeting could help determine — among other things — a timeline for when the project could be completed, the Garcias said.
Richard Garcia said the information collected by drones will play an important part in future decommissioning and decontamination at the plant.
Visit unmannedsystems.swri.org for more information.