Sarah Downs Equips NASA Robots With Assembly Skills

This year, a member of IEEE graduate students realized that dream. In his final project as a master’s degree candidate in electrical engineering at the University of Tulsa, he worked on a project in collaboration with NASA and the US Air Force.

The algorithm he developed enables a robot that assembles satellites in space to put an antenna in the right place, tackling the classic peg-in-hole robotics problem of inserting an object into a corresponding hole.

He now holds a Ph.D. student in electrical engineering at Texas A&M University in College Station, Downs continues his research on satellite integration and manipulation “but on a much larger scale,” he says.

Following a childhood passion

Downs grew up in the Tulsa area. His father, who died of a heart attack in 2015 when he was 13, was a safety consultant in the oil and gas industry. His mother stayed home to take care of his brother, who has autism. After her father died, her mother went back to college to get a business degree so she could support the family.

“We didn’t make much money, and my mother was always worried about money,” Downs said. “That made me more aware of having a successful career, financially.”

From then on, whenever he considered his future career, having a good income to support his family was at the top of his list.

By pursuing a career in robotics, he says, he can follow his passion while gaining financial security.

In high school, Downs joined the First robotics club, where he found himself fascinated by the electronics used in the machines he and his classmates built.

During his last two years of high school, he participated in an extension program at Tulsa Tech, a training school. He spent half of his day in high school classes and the other taking engineering courses at a vocational school.

After graduating in 2020, he accepted scholarships to attend the University of Tulsa. He started his freshman year at Tulsa not knowing whether he wanted to major in electrical or mechanical engineering, he says, adding that his love of working with small systems helped him choose EE.

For his senior year capstone project, he and two of his classmates designed a moon exhibit for the Tulsa Air and Space Museum. They created an interactive game that simulates travel to the moon and martian space. Four celestial bodies—the moon, Venus, Mars, and Titan—are programmed across three computer monitors. Using a game controller, museum visitors can explore each of its virtual spaces. The show is still on.

Downs received his bachelor’s degree in electrical engineering in 2024 and continued his education in the university’s EE master’s degree program.

Both are more complicated than people think

When Downs began his graduate studies, he was to be part of a NASA robotics project for two years. But when delays in government funding delayed the start of the project, he instead spent his first year at the school’s Institute for Robotics and Autonomy, which had just been launched. Its main goal is to develop robots to help people with mobility challenges.

Inspired by his grandmother, who was confined to a wheelchair due to severe arthritis, Downs created a robotic arm that helps elderly people in wheelchairs live independently. The arm was able to identify and place items in the right places within the home, such as presenting certain groceries in a shopping bag and placing them on a shelf or in different containers.

Before the start of his second year in 2025, the NASA project finally received government funding. He built a robot that accomplishes the peg-in-hole task without using any vision systems. In general, cameras help guide the work of satellite assembly robots. But in the harsh, remote environment of space, cameras may malfunction or experience delays.

Rather than using cameras, Downs’ robotic arm uses a force-based input process to sense the position and orientation of objects in the arm’s vicinity. The robot simply grabs the antenna and, with a torque sensor in its gripper, “feels” the force feedback of where the satellite and antenna are relative to each other. The robot then guides the assembly of sticks to the target opening on its satellite and maintains the position where it attaches.

Adding to the complexity, the robot does its work in zero gravity.

“In addition to gravity, you now have to consider the torques of the satellite’s arm to avoid throwing it into space,” Downs said. Any movement from the arm during the installation process, especially from increased power, can cause the satellite to continue moving in that direction.

To combat that, Downs developed the project’s calculations to guide the thrust and counterbalance of the robot’s motion.

His graduation project captures the simple yet complex nature of robotics that he finds fascinating, he said.

He says: “I think robots are more and more complex than people think. “Actually, all you need to start programming a robot are its Denavit-Hartenberg parameters, and you can do a lot with that,” he said, referring to the four values ​​used to define the position and shape of a robot’s arm and manipulators. Even with different grippers and degrees of freedom, “basically, all robot manipulators start there,” he said.

He adds: “But we are still learning a lot about how robots interact with the environment.” Even something simple for us, like using a pen, is still incredibly complex for robots.”

Downs is completing his doctoral thesis on the Robotic Space Simulator project at Texas A&M’s Robotics and Automation Design (RAD) Lab, which focuses on developing machines that can survive in extreme environments. Collaborated with NASA.

Her thesis advisor is Robert Ambrose, a NASA veteran who founded the RAD Lab in 2022. The IEEE member will serve as associate director of the school’s Space Institute, which is slated to open this year in Houston. A research facility was built near the Johnson Space Center.

After receiving his Ph.D., Downs says, he hopes to one day work for NASA, developing rovers that collect samples on Mars or robotic arms that perform tasks on space stations.

To learn more about robots, check out IEEE SpectrumThe guide.

Getting out of the engineering bubble

Downs joined IEEE in 2020 as a freshman at UTulsa to be more involved in electrical engineering events on campus. At the time, the COVID-19 pandemic prevented clubs and organizations from meeting in person.

He was active in his school’s IEEE student branch and was elected its president for 2022–2024. Under his leadership, the branch went from having few events to holding one every two weeks.

They included lunch and study sessions and dinners that connected students with professional engineers and university students. Downs also organized hands-on workshops on soldering, 3D printing, CAD modeling, and CV building.

His efforts helped increase the membership of the branch board from about five students to 25 by 2023. That same year, his workshop attracted about 80 students.

He says he enjoyed working with IEEE, especially “interacting with alumni and learning from engineers.”

IEEE is a great resource for networking opportunities, he says, noting that “during the violence of COVID-19, engineering students are living in their bubbles.” IEEE events have helped students make connections that will serve them well, he says.

“Communication is very important, especially in this tough job market,” he says. “There’s a lot you know and how people perceive your work.”

Downs, who now works as an IEEE graduate advisor for the Tulsa student branch, says he has seen first-hand how the school’s network of student branches has benefited its members.

“Most of them got jobs” because of IEEE, he says.