UC students design custom satellites

When you want to solve a big problem, sometimes perspective makes all the difference.

Engineering students at the University of Cincinnati are building tiny custom satellites to help scientists study some of the Earth’s most pressing environmental problems from space.

Andy Barth, an aerospace engineering student, is designing a 10-centimeter-cubed satellite, called a CubeSat, that will be deployed from the International Space Station to track the temperature of the sea surface in the Amazon River delta.

CubeSats are inexpensive, simple and reliable compared to bigger commercial satellites. Each is customized to perform a specific task. They are launched into a low, decaying orbit that gives them a narrow operating window before they eventually incinerate in the atmosphere. This keeps them from becoming dangerous flotsam to other passing satellites or launching spacecraft.

Barth is working on his project with an Ohio company called Sierra Lobo, Inc.

“This is more of a technology demonstrator to try out different sensors,” Barth said. “Their hope is to fund a bunch of these CubeSats to collect data from orbit.”

The student projects demonstrate UC's commitment to research as part of its strategic direction called Next Lives Here.

Overseeing the project is Ou Ma, a professor of aerospace engineering in UC’s College of Engineering and Applied Science. He directs UC's Intelligent Robotics and Autonomous Systems Laboratory.

Ma has spent his entire career developing new space technology. He has worked on complicated undertakings for NASA like the robotic arm for the space shuttle — projects that took teams of engineers, physicists and specialists. His name is floating 254 miles above the Earth aboard the International Space Station after he and other engineers signed their autographs on one of their completed projects.

Designing and building a CubeSat is comparable to working on team projects the student engineers will tackle on the job. Students must make everything work in service of the mission priorities, she said.

“They are practicing the techniques they’ll be using at NASA or SpaceX or anywhere else,” McGhan said. “They have to design something within very tight constraints. And that’s how all space missions are. You start with your problem and work toward a solution.”

McGhan said students quickly learn that solving one problem can create new ones.

“It’s not an easy thing to do. It’s rocket science, after all,” she joked.

In their labs, both Ma and McGhan look for engineering solutions to Newton’s third law of motion: every action has an equal and opposite reaction.

Many satellites, including UC’s HABsat1, must be able to orient themselves in a vacuum. But that’s easier said than done.

“Astronauts trying to turn a doorknob in space will turn themselves instead if their feet aren’t planted,” McGhan said.

UC’s HABsat1 relies on a clever internal flywheel system that puts Newton’s laws into practice. Motor-driven spinning flywheels can orient a satellite on three axes. That’s how NASA aims the Hubble Space Telescope.

In his lab, Ma tests new navigation and control systems on what looks like an air-hockey table that elevates a robot on a cushion of air. This mimics the frictionless vacuum of space, at least on two axes.

“Testing a satellite is always a challenge. To duplicate the conditions of space on the ground is not easy,” Ma said. “We have this flat plane that can test the attitude and control capability of the satellite.”

UC graduate Alex Walker co-oped for Sierra Lobo, which deployed one of his satellites in February.

“It’s a cryogenic fluid experiment. It has a pressurized xenon tank. A sun shield points to deep space to cool the tank to cryogenic pressures and liquify the xenon on orbit,” he said.

Now Walker is working on a second satellite project aimed at measuring the polarity of reflected light off clouds to determine their ice density. He hopes it can be used to predict snowfall to improve weather forecasts.

UC’s College of Engineering and Applied Science is developing the latest innovations in autonomous navigation using artificial intelligence called fuzzy logic.

Ma said NASA and its contractors are risk averse, preferring proven technology even if it’s antiquated by comparison.

“The space industry is one of the most conservative for innovation. They don’t want anything new because new is not reliable. So if it fails, it’s a big loss,” Ma said. “But I’m sure NASA will embrace these new technologies.”

Featured image at top: UC student Andrew Barth stands in front of a mock satellite used to test attitude and control systems in UC's Intelligent Robotics and Autonomous Systems Laboratory. Photo/Joseph Fuqua II/UC Creative + Brand