Designing Tools and Tech for Future Space Exploration with LunaMOTH
At Embry-Riddle Aeronautical University, undergraduate students studying Spaceflight Operations, Engineering, and Human Factors are using their brilliance to design and prototype tools for space exploration. Pretty out of this world, right? The Protolabs Cool Idea Award manufacturing grant funded prototyping for CNC-machined components comprising the bulk of their Lunar Modular Operations Tool Holster (LunaMOTH).
A Call to Action: Solving a Space Exploration Challenge
As part of NASA’s Micro-g NExT program, the students in the university’s Spacesuit Utilization of Innovative Technology (SUIT) Lab spend the academic year conceptualizing, prototyping, and testing a solution to a specific space exploration challenge. These efforts culminate with rigorous testing in NASA’s simulated microgravity environment, the Neutral Buoyancy Laboratory (NBL).
The Micro-g NExT challenges vary from year to year and undergraduate students from colleges across the country submit proposals to develop real tools to be used in space. While research for shorter spacewalks has been the priority in years past, there’s been a sizeable shift to focus on longer and more routine space missions for the Artemis program (slated to return astronauts to the moon by 2024), including new infrastructure to live and work in space more permanently. “Those challenges are all centered around real problems that NASA is trying to solve for real space flight missions,” said Thomas Burghardt, engineer and 2022 graduate of ERAU.
Facilitating Lunar Research with LunaMOTH
For their 2021 Micro-g NExT project, the SUIT Lab team created LunaMOTH to help astronauts easily remove and replace a tool on the spacesuit utility belt during work on the lunar surface. The attachment system has two interlocks. The tool-side interface is a protruding knob on an oblong neck that slides into a slot on the suit-side interface. Spring plungers installed in the sides of the slot add resistance to help keep the tools in place when not removing the tools from the holster. Tools that astronauts may use in conjunction with the LunaMOTH are cameras and lunar geology testing tools like chisels, hammers, and markers.
Dust tolerance and ease of use were two mission critical priorities that the SUIT lab team kept top of mind while designing LunaMOTH. They ensured the device could remain operable even if completely covered in lunar dust and that the astronaut could operate the system easily
with minimal visibility and mobility. We CNC-machined the primary
pieces of both final designed LunaMOTH components were with
abrasion-resistant stainless steel.
“You can design a tool that’s easy for someone who isn’t wearing a spacesuit glove or helmet with limited visibility, but once you’re in space and you can’t quite bend over as much as you’d like to, all of those things make it harder to use different tools,” said Burghardt. “Our lab does a lot work to make sure that when we design tools for those applications, people wearing spacesuits will still be able to use them.”
Ideation, Iteration, Testing, Repeating.
Evolving LunaMOTH’s design throughout the ongoing testing process was key. The team’s testing methods included submerging plastic and aluminum prototypes in sand to ensure the device still worked properly even if covered in lunar dust. The team tried the device on different areas of the user’s body, including some that were out of the line of vision. Weight was another consideration as they tested tools of different sizes and weights up to 15 lbs. (6.804 kg) to ensure tools would remain secure during operation.
Once the team was comfortable using the device on dry land, they took it underwater for further testing. The underwater environment mimics the testing that NASA does at the NBL, and is the best way to simulate microgravity, whether the zero-G of space or 1/6 of that when you’re on the moon.
Because LunaMoth is a smaller design, the team was able to do some in-house 3D printing for very early prototypes. We got through a lot more iterations with LunaMOTH than we did on most other projects that require bigger or more complex assemblies,” said Burghardt. “The more iterations you do, the better your product will end up. We also joke that at the end of every year, the engineers that have built the product are the ones who know all the flaws in it and know everything they would change if they got one more design iteration.”
Working with NASA: NBL testing
Once the SUIT lab team was happy with LunaMOTH’s nearly final design, they traveled to the NASA Johnson Space Center NBL. Professional divers test the student groups’ tools while the teams direct the divers to complete a series of tests from a control room. The team received positive feedback on LunaMOTH, compiled some additional data analysis, and reported back to NASA with a proposed final design. Be sure to check out the NBL testing footage!
But what happens after all that hard work? Do these inventions ever make it to space? Burghardt likens NASA’s Micro-g NExT program to a research and development program. “There have been tool designs that NASA has adopted as is. They got them flight ready and they’ve flown to space,” he said.
Partnering with Protolabs for Digital Manufacturing Needs
LunaMOTH isn’t the first SUIT Lab project that Protolabs has manufactured parts for. “We've used a couple processes for these different projects. “Protolabs is very familiar with aerospace applications and NASA is very familiar with Protolabs’ work, so when we tell NASA a component is going to be from Protolabs, they know exactly what kind of quality to expect. We’ve also been very fortunate to work with a lot of really good folks at Protolabs. Everyone has been super helpful answering all of our questions,” said Burghardt.
Prior to LunaMOTH, the SUIT lab partnered with Protolabs on 3D-printed components for STAR (Specialized Tool for Astronaut Recording). The GoPro-like camera mount attaches to handrails outside of the International Space Station and offers a new view to monitor astronauts. This year, the SUIT lab team has been hard at work on PRISM (Photo Reference and Identification Sample Marker), which is placed on the lunar surface where an astronaut might want to collect a sample. When the site and marker are photographed, the color swatches on the device help color-calibrate the image. The marker also provides a size reference for scientists to pick and choose which sample sites look most interesting. Both STAR and PRISM included Multi Jet Fusion 3D-printed components in PA 12 Black, a high tensile strength nylon.
“Flight hardware in space is almost always metallic due to thermal constraints, but for testing at NASA’s NBL, metal isn’t required. For cost considerations, we went with a lower cost Multi Jet Fusion option,” Burghardt said. “The components for PRISM are pretty large. The device needs to stand tall on the lunar surface. That’s another reason why we went with Multi Jet Fusion from Protolabs. It’s a nice low-cost way to produce strong components for NBL testing.”
Passing the Torch to STEM’s Next Gen
Somehow Burghardt and his fellow SUIT Lab team members find time for additional educational outreach. “That’s a big requirement for NASA that we continue to work with other students younger than college-age not only about the space program, but engineering and STEM in general. Our group starts with a list of requirements for a prototype that’s high fidelity for space. This is a pretty major testing process that gives the students on our team a great way to learn the design process, which sometimes isn’t something students get to do until their senior design courses.” This knowledge transfer has gotten younger students fired up about the SUIT lab and the Micro-g NExT program. A handful of freshmen have already joined over the last year or so.