Students conduct zero gravity experiment via NASA program

The Moon Goons, an interdisciplinary team of Illinois students that included three ECE seniors, experienced zero-gravity through the Microgravity University program at Johnson Space Center while conducting an experiment entitled “autonomous and adaptive docking in variable gravity.” The goal was to fly the drone in zero gravity and have it dock on a landing station using magnets to induce eddy currents, causing the drone to brake.

NASA’s program creates a reduced-gravity environment on a modified Boeing 727-200. The airplane flies parabolic maneuvers over the Gulf of Mexico, resulting in periods of hypergravity (about 1.8G-2G) and microgravity (0G). This provides a chance to perform experiments in zero-gravity within the earth’s atmosphere. The highly competitive program is open to any undergraduate students in the country, who are accepted through a proposal process conducted seven months before the flight date.

The Moon Goons formed after team leader Danylo Hirnyj, a physics major, went through the program in 2011 and began finding friends to start the new group and formulate a worthwhile experiment. Ultimately the team chose to fly and dock a drone in zero gravity.

The drone was placed in an enclosure to constrain it to two degrees of freedom, able to rotate and move vertically. It would align to the docking station, and then the docking station’s magnets would cause the drone to brake by inducing an eddy current, similar to the way roller coasters brake.

The team faced some challenges in accounting for all of the variables. “There were certain variables that we couldn’t figure out without actually testing in zero gravity first,” said ECE senior Sunny Gautam in an interview with CS lecturer Lawrence Angrave, the team’s mentor. The team did what they could to simulate certain effects of the gravity difference on their experiment, such as “removing the bearings we use for rotation and just hanging it off a lamp so we can account for center of gravity,” but they knew the real test would be the first of their two flights in the plane.

Alejandro Gomez, another ECE senior in the group, worked on the control algorithm for the drone. One of the main variables he had to deal with was the difference in force needed to move the drone under different gravitational circumstances. He predicted that in zero gravity, “with the smallest force the drone will move a lot compared to how it moves here [in the earth’s gravity].”

The enclosure around the drone, however, provided more friction against the drone’s momentum than expected. The drone did not reach the docking station during its attempts on the first flight. On the plane, the team fervently worked on changing the algorithm to increase the drone’s thrust, recoding in zero gravity, double gravity, and everything in between. Gomez joked that coding in double gravity is “not as easy as on your couch.” Between the two flight days, the team continued their recoding. The changes in the algorithm were partially effective, and during the second flight the team succeeded in flying and docking their drone during one of the parabolas.

Ultimately, the team took a lot away from the program. Ehsan Keramat, the third ECE student in the group, said, “It’s an experience you can’t get anywhere else.”

“More people have climbed Mt. Everest than have been in the zero gravity plane,” added Gomez.

One of the most important parts of the experience for the ECE students was working alongside team leader Hirnyj and teammate Sam Liu, a senior in computer science. This not only gave them the chance to work with peers of different majors, but they were also able to expand their experience, using their ECE education as a foundation and supplementing it with other skills.