The Ohio State Team presenting at the Human Lander Forum in June. Credit: Courtesy of Preston Harmon.
What began as an idea sketched out by Ohio State students has now become an award-winning prototype that could one day help astronauts refuel their way to the moon.
The students’ work was named best prototype on June 26, in NASA’s Human Lander Challenge, which was held near the Marshall Space Flight Center in Huntsville, Ala.
In the Human Lander Challenge, participants were tasked with developing in-space solutions for storing and transferring cryogenic liquids to support future long-term exploration, according to prior Lantern reporting. Used as propellants in spaceflight, gases hydrogen and oxygen must stay extremely cold to stay in a liquid state.
John Horack, project advisor and the Neil Armstrong Chair in Aerospace Policy at Ohio State, said that the fuel in space is drastically different than on Earth.
“The cryogenic fuel is basically supercooled hydrogen oxygen,” Horack said in an interview. “You take those gases and cool them down, almost, in the case of hydrogen, to about 20 Kelvin, just above absolute zero. In this case, then you have to try to figure out how to hook it up.”
Max Heil, the team project manager and graduate aerospace engineering student, said that since cryogenic liquids only last several hours in space, experts must find a solution to make the gases last several weeks or even years.
While other teams focused on categories like thermal methods to reduce boil off or refueling on the moon, Ohio State’s team chose to work on autonomous refueling to build an innovative solution in a key aspect of NASA’s missions to the moon, Heil said.
“It was really just any way you could think of to reduce that amount of thermal loss or increase the longevity of cryogenics,” Heil said.
Autonomous refueling can speed up the process of transferring fuel from a tanker to a spacecraft, Heil said.
Their prototype, Autonomous Magnetized Cryo-Couplers with Active Alignment Control (AMCC-AAC), was modeled after a Stewart Platform, which is a six-legged motion table that the International Space Station uses to dock spaceships, said Heil.
The team wanted to replicate the platform and apply it in space for the cryogenic system, where the table can be used to latch the two spacecrafts together to refuel through the port, said Heil.
The AMCC-AAC uses a computer vision system that identifies “AprilTags,” similar to how QR codes work, located on the other side of the spacecraft to make the exact movements it needs to make to connect and start refueling, Heil said.
Their functional prototype wasn’t the team’s initial idea for how they wanted to represent and build their concept.
“When we were initially thinking about the prototype, we were thinking, ‘Okay, let’s just 3D print a model or for our equipment,’ which is great to do, but a lot of other teams were going to do that, and we kind of knew that,” Heil said. “So to set us apart, I had the idea that we should kind of expand upon this whole thing, and our paper emphasizes the whole movement system, and while it’s not really a novel idea, it’s unique in space.”
Despite a large team with varying schedules, Heil said they were able to build the prototype in four months.
“I think we were all just really good at communicating, Heil said, “and when everybody communicates in that way, it makes the project move faster.”
Horack said his role as the team’s advisor was consultative rather than very directive; his job was to help them stay on track and use his resources to support them in the best way he could.
Horack also said he was pleased with the success of his students with their prototype. While their team did not place first overall, they still built something worth celebrating, according to Horack.
“For me, they didn’t win first or second or third place, but they got the best prototype,” Horack said. “I’m thinking, well, isn’t that what engineering is all about? Building something.”
Heil said that Horack supporting graduating engineers like himself can help open doors and connect with other industry experts.
“I think his support went beyond just technical,” Heil said. “It was definitely relationship building and pretty instrumental in how students can connect with the industry.”
The team will continue the project with other partners or advance related projects relevant to the space industry, Heil said. At Ohio State, there has been a lack of emphasis on the space side of aerospace, and the team is hoping to change that.
“I think this competition really boosts our awareness and the notoriety that we have in space at Ohio State and it shows that we are working on projects that are space related,” Heil said. “So it’s huge for the university. It really is huge.”
