A giant Nerf launcher
The NASA competition requires the entire system to weigh under 15 kilograms, because it’s expensive to send things to space. The Luminosity team’s solution was to create something disposable.
“Really the only data we need to collect is whether or not there is water in the crater. A device doesn't have to come back. Just the data. The data doesn't weigh anything, and we can more easily retrieve that than retrieve the whole system,” said Collin Schairer, an electrical engineering junior and the current team lead.
They decided to create a set of four small probes that would be sent out by a launcher.
“It’s basically like a giant Nerf launcher,” said Gowan Rowland, a mechanical engineering senior who worked on the design and mechanical build of the system. “It's a spring-loaded assembly. All the stored energy that launches the probe is in a compressed spring.”
Here’s how it works: The launcher, attached to the moon lander, will send out three probes at different distances from the lander in the direction of a PSR. Each probe carries equipment to measure the temperature of the surface it lands on, its acceleration as it lands and which elements are present in its surroundings. Taken together, this data will tell scientists about the environment inside the PSR, including whether it contains ice.
If the three probes are unable to send their information back to the launcher for some reason, it will send out the fourth probe, which will collect and transmit the other probes’ data as it flies above them.
Each softball-sized probe will fly at roughly the same velocity as a regular softball thrown by a person. The special electrical equipment inside them can’t stand the frigid temperatures of a PSR for very long, so the team had to find some of the best insulation in the solar system.
Surrounding the probe’s aluminum shell is a series of fabric and plastic sheets called multilayer insulation that will keep the interior warm enough to operate for as long as possible. The outermost layer is beta cloth, which NASA has used on space suits as well as the Mars Curiosity rover and the International Space Station. It’s made of Teflon-coated fiberglass and is a popular choice for outer space protection because it’s durable, insulating and fireproof.
“I jokingly refer to it as the world’s most expensive baseball sweater,” Schairer said.
Thinking beyond the BIG Idea Challenge, the team wanted to create something that could be applied to a variety of experiments and environments. Their simple, effective design is intentionally scalable and modular so that other science teams can adopt VELOS to their needs, whether that be using more probes, taking other kinds of measurements or deploying it on other moons or planets.
Testing, testing …
To make sure their system is moon-ready, the students put it through multiple tests, both in computer simulation and, leading up to their report submission, real-world experiments.
To test the heartiness of their probe design and ensure it won’t break on impact, they launched it onto a hard rubber surface that’s less yielding than the moon dust researchers have studied so far. (Although we’ve yet to examine moon dust from the polar regions, and variations exist, our present knowledge is that it’s typically very fine, somewhat like the flour in a household pantry.) The probe performed so well, Rowland said, that the team may use less material on the probe’s shell in future design iterations to make it lighter.
The students collaborated with the ASU Interplanetary Initiative to conduct two other tests that need special equipment.
“Space is obviously really cold; space is also a vacuum. So we wanted to test those very harsh conditions,” said Julia Greteman, a sophomore in material science and engineering who helped select and test the materials used in the VELOS design. “The battery is our weakest link, so we're trying to verify that it will be OK for this purpose.”
Using a vacuum chamber, the team placed their probes in a very low-pressure environment to simulate the moon (which has no atmosphere and is surrounded by a vacuum) in order to see how it impacted the battery’s performance. They also put their probes through thermal testing by using liquid nitrogen to quickly cool them and then taking them back out.
The students also made use of the ASU Drone Studio, a new, indoor motion-capture facility belonging to the Ira A. Fulton Schools of Engineering. The space is equipped with cameras that can track objects as they fly through the air — perfect for testing the launcher and calibrating the spring strength needed for the appropriate launch distance in low gravity.
On top of the pressure to create an out-of-this-world technology system, the team also faced the unforeseen hurdle of the COVID-19 crisis, which came about just weeks after NASA announced them as finalists.
“That's been a big challenge for us through this whole process, because Luminosity tends to be a very collaborative group of people,” Schairer said.
Group brainstorming sessions with students scribbling frantically on whiteboards and windows had to be replaced with virtual meetings. To keep the sense of collaboration strong, however, each sub team on the project met biweekly, ensuring that communication continued flowing. For the necessary lab testing, the team limited the number of people present and followed ASU’s preventative COVID-19 guidelines.
“It's not ideal, but we've made it work,” Schairer said. “I'm really proud of the work that we've done since February.”
Moon walk, virtually
As if designing a mission-ready space instrument during a pandemic wasn’t enough, the team included a surprise with their final report submission— an educational virtual reality application to go with their project.
The program puts viewers on the moon as astronauts. They can go to different stations on the lunar surface, where they learn about PSRs and how the system works, watch the lander touch down, see the launcher in detail, hold a probe and even hit a button to manually launch a probe. Although the actual system would operate autonomously on a real mission, this program gives a hands-on experience so viewers can better understand the design and its goals.
“I think it’s a unique opportunity for storytelling to provide someone a first-person experience of this project on the moon, given that obviously no one is going to be able to see it like that,” said Dylan Kerr, a digital culture master’s degree student who led the team that developed the VR environment.
Although he admits that they’re hoping to wow the judges, Kerr notes that it could serve as an engaging learning tool for the general public as well. A run-through of the VR experience is available to watch below or on YouTube.
All of the planning, designing, building, coordinating, testing and presenting that this complex project required has given the team a unique level of preparation for life after graduation, their mentor notes.
“Competing in a NASA project and learning about the methods, standards and traditions used by successful NASA engineers is helping to provide an important foundation for potential future careers in aerospace,” Bell said.
Taken as a whole, it’s not hard to see why this project involved over a dozen students from multiple backgrounds: industrial design, programming, robotics, materials science and electrical engineering, to name a few. That collective approach, said Schairer, made the team much more effective than any one of them could have been on their own.
“That's kind of the point of Luminosity — being able to rely on everyone's strengths and tackle a complex problem with creative solutions.”
The ASU team is scheduled to present VELOS to the competition judges on Jan. 7 at 3:10–4:10 p.m. Eastern Standard Time during the publicly livestreamed 2020 BIG Idea Forum. Any changes to the schedule will be posted to the BIG Idea livestream link prior to the forum.
This project is funded in part by the Arizona Space Grant Consortium, whose mission is to expand opportunities for Americans to learn about and participate in NASA's programs by supporting and enhancing science and engineering education, research and outreach and by delivering high-quality public education programs.
The Luminosity Lab and the Interplanetary Initiative are partially supported by Arizona’s Technology and Research Initiative Fund. TRIF investment has enabled thousands of scientific discoveries, over 950 patents, 328 startup companies and hands-on training for nearly 39,000 students across Arizona’s universities. Publicly supported through voter approval, TRIF is an essential resource for growing Arizona’s economy and providing opportunities for Arizona residents to work, learn and thrive.
Top photo: (From left) Andrei Marinescu, Tyler Smith and Gowan Rowland calibrate the launcher inside the ASU Drone Studio. Photo by Andy DeLisle/ASU