SDSU a NASA finalist … again! Engineering students develop design for crater-exploring rover

Building on the tradition of past student entries in NASA contests, another group of South Dakota State University engineering students has advanced to the finals of a NASA contest.

This year’s group of five mechanical engineering students will appear before NASA judges to present their idea and prototype of a rover that can explore rugged and permanently shadowed lunar south pole craters searching for water, ice and other volatiles. They are one of 14 teams nationwide that will be in Cocoa Beach, Florida, June 10-12.

NASA selects finalists for four categories in its Revolutionary Aerospace Systems Concepts – Academic Linkage (RASC-AL) competition. SDSU is competing in the large-scale lunar crater prospector category against Iowa State, Tulane, Maryland and Texas universities.

SDSU’s 2023 RASC-AL team had the best entry in the lunar surface transporter vehicle category and was honored for building the best prototype of any of the four categories. The 2024 team aims to repeat that honor as well as being selected an as overall top two entry.

State’s engineers will face two of the same competitors — Maryland and Texas — that it competed against in 2023.

This year’s SDSU team is totally new, except for Liam Murray, who transitioned from team lead to graduate adviser. The undergraduates are Delaney Baumberger, team lead, Blair, Nebraska, senior; Alex Schaar, Sioux Falls, senior; Dylan Stephens, Redfield, senior; Aiden Carstensen, Cedar Rapids, Iowa, sophomore; and Braxton McGrath, Amana, Iowa, sophomore.

The team’s entry is dubbed POSEID-N (Prospecting Observation System for Exploration, Investigation, Discovery, and Navigation rover).

A good problem to have

Continuing as faculty adviser is Todd Letcher, an associate professor in mechanical engineering.

“We will have the smallest team (at the finals) by a significant margin. That is a huge testament to everybody on the team. The amount of work didn’t decrease (from past years). This team has worked so hard. They’ve put in a ton of time conducting research, developing a concept and building a prototype,” Letcher said.

“I’m really excited for them to get to go and be able to interact with judges and other contestants and visit Kennedy Space Center. Last year was just a terrific experience.”

Ironically, because of school’s success in other NASA contests, Letcher may not be able to go. He has already committed to be in Huntsville, Alabama, for the finals of the Break the Ice Lunar Challenge on the exact same dates. SDSU is one of six finalists in that contest that includes colleges and corporations with a $1 million top prize and a $500,000 runner-up prize.

Murray shows great leadership

If Letcher isn’t able to break away from the Break the Ice contest for a day, he is confident in the leadership of Murray and the dedicated students.

“Liam understands the commitment this contest demands and set the tone for this group as well as being a great resource for them. Having Liam return here for graduate school and serve as my right-hand man has been invaluable,” said Letcher, who also teaches a full load of classes and oversees numerous senior design projects.

The contributions of Murray, of Omaha, Nebraska, haven’t gone unnoticed by the team.

Baumberger, the team lead, said, “The guidance Liam gave us from his experience last year was very helpful, especially in early design phases.” 

Schaar added, “He kept guiding us in the right direction, and the amount of hours he put in addition to helping with other students’ projects, being a grad student and swimming, it means a lot to the team.”

Three on team SDSU swimmers

Murray, who competes in sprint freestyle and backstroke, is one of three swimmers on the RASC-AL team. Carstensen is a backstroker, and McGrath specializes in the butterfly. 

They aren’t on the team by coincidence. Murray recruited the fellow mechanical engineering students because he could see that the dedication they had in the pool would translate well to the engineering lab.

“Liam extended the opportunity, and we wanted to explore it. We’re thankful they are willing to pass on their knowledge and experience to us,” Carstensen said.

McGrath said, “As sophomores, we played a much more supportive role. To watch them (the seniors) work and to be able to understand the process better is a priceless experience.” 

Potentially a patented product

However, the sophomores weren’t strictly observers. Murray said they took the lead role in simulated lunar testing, which, in simple terms, involved putting the rover prototype in a sandbox and seeing how well it could maneuver. The most innovative feature of the rover prospector is a double wishbone bogie suspension system.

A bogie system, a modular subassembly of wheels and axles (think of a rail car), are common in space applications, Stephens said.

However, the double wishbone feature (think a wheel on each end of a “V”) is unique. Rather than four wheels in traditional locations, there are double wishbones at each of the points, thus a total of eight wheels. There also are linear actuators at each of the four corners to allow for vertical movement, Murray said.

In fact, the students’ design is unique enough that they have submitted an invention disclosure, the first step in the patent process.

‘Ton of work’ remains

NASA had promised to announce on April 5 which of the 75 entries advanced to the finals. Baumberger said she started checking her email at 7 a.m. By noon she had gotten word from Letcher and a NASA official. Stephens said, “I was super excited. We didn’t want to be overconfident, but we knew we had a good project, so we weren’t shocked. However, it was still an exciting moment.”

The NASA judges also shared pros and cons on their project. “They loved our idea and said we did an amazing job in the details of the mechanical design,” Stephens said.

Between now and June 10, there is a “ton of work” to be done, he said. However, most of the mechanical work is complete. Students must write a full technical paper, create a poster board and prepare a 30-minute presentation to a panel of NASA and aerospace industry leaders, who will then pepper them with questions.

Contest a career launching pad

Baumberger welcomes the opportunity to interact with them, both formally and informally. She notes the time in Cocoa Beach includes a career fair.

She desires a career in aerospace. It’s not a pie-in-the-sky dream. Out of last year’s six-member team, five are working in the aerospace industry or in graduate school with an aerospace emphasis. Nick Stegmeier, who had a summer internship at Johnson Space Center in Houston after graduating, now has been awarded a major NASA fellowship.

Letcher said, “All (of the 2023 team) turned out amazingly well, and I would expect nothing else from this group.”

All three seniors are returning to SDSU for graduate school for a master’s degree in mechanical engineering with an aerospace engineering emphasis. The two sophomores will be back with a “roll the sleeves up” mentality.

The SDSU tradition of success in NASA contests shows no sign of stalling out. 

The video the team submitted to NASA can be seen on YouTube.