A team of University students led by Engineering Prof. Mool C. Gupta received awards for Best Technical Poster and Best Technical Demonstration for its innovative project in NASA's 2020 Big Idea Challenge. The project — entitled Beaming of Energy via Lasers for Lunar Exploration — focused on powering devices in dark areas on the moon that receive no sunlight by using lasers to transmit energy to rovers. During the design process, the team had to overcome difficulties associated with working on their project in light of COVID-19 restrictions.
The Big Idea Challenge is a competition that provides undergraduate and graduate students the opportunity to design, test and build solutions for that year's challenge and support future NASA missions through competition projects. In 2020, NASA sought to address a challenge that they face with their Artemis program.
NASA's Artemis program seeks to return humans to the moon by 2024. Robotic precursor missions are being carried out to reduce technical and programmatic risks to humans and seek to explore regions of the moon of interest to human explorers using rovers. Areas of high interest are the permanently shadowed regions near the lunar polar regions that have been dark for billions of years. The problem lies in getting energy for the rovers, which typically use solar panels.
“At the top of the craters, there is plenty of sunshine,” Gupta said. “The idea we proposed is to harness the sunlight at the top of the craters, convert the solar light to electric power and use it to run a laser. That laser light can be beamed into the permanently shadowed regions and also can be tracked to provide power to a moving object like a rover.”
Gupta was uniquely equipped to tackle this problem, as the director of the National Science Foundation-funded Center for Laser and Plasma for Advanced Manufacturing.
After learning about the challenge’s focus, Gupta contacted fourth-year Engineering student Jacob St. Martin, who had done previous research in Gupta's lab. St. Martin was interested in the project, and they began assembling an interdisciplinary team.
"The nature of our project, as opposed to even some of the other projects in the competition, is that it was a very interdisciplinary project," St. Martin said. "There were a lot of electrical components, programming components, mechanical design, lasers and optics. A lot of different systems that had to be brought together."
The team of students included graduate Engineering student George Wilkes, third-year Engineering students Rex Serpe and Julia Rudy, fourth-year Engineering student Keerthi Radhakrishnan and second-year Engineering students Edward Lee and David Chen.
St. Martin was the student team leader and mechanical design lead. Wilkes was the laser, optics and photovoltaic team leader. Serpe was the laser tracking and embedded systems team leader. Rudy was the rover and gimbal tracking team leader. Radhakrishnan was the charging systems team leader. Lee and Chen were the data representation and thermal control team co-leaders.
Gupta also recruited Paul Jaffe — an electronics engineer with the Spacecraft Engineering Department at the U.S. Naval Research Laboratory who has been working on power beaming for defense applications — as an external advisor to help answer higher-level questions.
“[We] flesh[ed] out the idea of BELLE, and then we put together a proposal and submitted that around early January of last year,” St. Martin said. “It wasn't until mid-February that we were notified that we had been selected.”
The team received a $123,000 grant and began work in March, but then the pandemic hit.
“Everything shut down as soon as we went to spring break,” Rudy said. We had to create this tracking system but we weren't allowed in the lab.”
Wilkes was the only member of the team allowed in the lab since he was a graduate student. However, the interdisciplinary nature of the project turned out to be an advantage for the team when overcoming this access issue.
“[It was] a lot of different systems that had to be brought together,” he said. “Because of all those different systems, we were able to work on it in pieces from people's homes,” St. Martin said.
Wilkes explained that the team had to coordinate over virtual meetings.
“Most of what we developed was theorized over meetings and tested at various group members’ homes using lower-cost parts,” Wilkes said.
The team went through several design iterations using inexpensive equipment and lower-powered lasers before the members ramped up to their final design.
Rudy — who was in charge of working on the gimbal, the component that controls the horizontal and vertical movement of BELLE — had to come up with creative solutions to replicate being in the lab. The gimbal had to be able to withstand a 100-watt laser.
"I wasn't able to use in-lab data for the gimbal,” Rudy said. “I had to estimate what kind of readings I might expect from the laser on the photovoltaic cell and how the gimbal should move in response. I was doing that at home with a flashlight and photodiodes."
Wilkes was surprised how many ideas worked well right off the bat.
"From my experience, this is pretty rare in research,” Wilkes said. Our tracking demo in which we tracked a ping pong ball with retroreflective tape worked very well and could even track the ball as it was being tossed up and down. Additionally, we were able to squeeze a huge amount of power out of a photovoltaic array smaller than a sticky note by beaming laser power."
Rudy remarked on how exciting the project is because of the innovative tracking algorithm.
“There's been power beaming before but there's never been power beaming that was mobile,” Rudy said.
Although the team was able to find a solution to the lack of lab access, their process was still hampered by the pandemic. According to Rudy, it was not until September that they were allowed back in the lab to combine the subcomponents of their project.
"[W]e did both laser power beaming and the optical track. Those things have been done before individually but never integrated together," St. Martin said. He explained that not being able to assemble it until a later date hindered their process. “It didn't give us as much time to go through debugging and working out the kinks in the system," St. Martin said.
Gupta commended the team for their dedication — the long hours the team spent working on their poster and coordinating their presentation paid off.
“We worked hard, even nights,” Gupta said. “Nine o'clock, 10 o'clock in the night having a student meeting to discuss the paper we had to submit to NASA.”
In January of this year, the team received awards for the best technical poster and the best technical demonstration. The team was notified of their awards during an awards ceremony zoom call with the other teams. Michigan Technological University won the challenge’s top honor. Gupta expressed his thanks to the students for their hard work and to NASA for giving the students the opportunity to think outside the box and compete at a national level.