Satellite built by Champaign firm, UI students about to set sail

Satellite built by Champaign firm, UI students about to set sail

URBANA — Late tonight, a group of University of Illinois engineers will gather around a computer screen to watch their baby take flight, then head out to a field north of Urbana at 3 a.m. to pick up its first "squawks" as it passes over the Midwest.

The small "CubeSail" satellite, more than a decade in the making, is set to launch sometime after 10 p.m. from New Zealand, hitching a ride on the Electron rocket from the commercial space company Rocket Lab.

Designed and built by UI engineering students and CU Aerospace, a Champaign technology firm, CubeSail will demonstrate a new technique for steering a "solar sail," a solar-powered satellite propulsion system.

CubeSail is actually two small cube-shaped satellites, known as CubeSats, each about the size of a 5-pound bag of sugar but lighter. The two cubes will be bolted together as they're launched but will separate near the end of their 18-month mission around the Earth, and the sail will then unfurl between them.

The 820-foot sail is made of a thin, flexible layer of aluminum that reflects light from the sun, which pushes against it and causes it to spin, creating propulsion, said Michael Lembeck, associate professor in the Department of Aerospace Engineering and director of the UI's Laboratory for Advanced Space Systems.

Rectangular solar sails have been tested before, but this one is different, Lembeck said. Its long ribbon of material can be twisted to steer the satellite, a more efficient approach than earlier models, he said. The goal is to validate that technique, which works in computer models.

David Carroll of CU Aerospace wrote the original proposal to NASA in 2005 to test the CubeSail technology and won funding in 2008, then contracted with the UI to develop it. He earned his bachelor's, master's and doctoral degrees in aerospace engineering from the UI.

The launch window opens at 10 p.m., and the CubeSail team will be watching Rocket Lab's video livestream from a classroom at Talbot Lab. Then they'll head out to their ground station north of Urbana, where they hope to begin communicating with CubeSail about five hours after it deploys from the rocket when it flies over Indiana, said UI electrical engineering senior Dawn Haken, student lead on the project.

"That's when we first get to talk to it," if all goes well, she said.

The sail can't be deployed until its orbit begins to decline toward the end of its mission because the FCC worried that the long sail could get tied up with the International Space Station at its higher orbit, she said. Once CubeSail falls to an orbit about 217 miles up, the team will deploy the sail, Haken said.

"After that, there's a lot of draft just from the atmosphere at that height, and it'll de-orbit in a couple of days," burning up upon re-entry, Haken said.

The first part of the mission will be useful for testing the satellite itself, which was developed at the university, she said. It's the first space mission for the Illini Sat-2, and the team will be able to test the radio, power system, software and electronics, she said. The lab is currently designing an Illini Sat-3, so "we'll learn what we did right and what we did wrong and what we need to change," she said.

If CubeSail works, CUAerospace can commercialize the technology as an alternate propulsion system that could be used for deep space missions, Lembeck said.

CU Aerospace worked with the university on a predecessor technology, known as UltraSail, designed for longer interplanetary satellite missions, Carroll said. Solar sails are much lighter than carrying chemicals for conventional propulsion systems, Carroll said, making satellite launches less expensive, he said.

NASA asked for a smaller version, and the result was CubeSail, he said.

It will be useful for other purposes, possibly even removing space debris from low Earth orbit, a growing problem, he said. CubeSail modules could be attached to larger spacecraft and deploy at the end of the mission to drag it out of orbit, he said. Or a CubeSail could be equipped with a small grappling hook that could "grab a piece of space junk and drag it down," he said.

CubeSats were developed as secondary payloads attached to bigger missions, Haken said. Anytime a satellite is launched, there's a little extra mass that the rocket could carry, and CubeSats are designed to fill that space and "do something useful," she said.

"They're piggyback missions," she said. "It's a cheap way to send satellites up."

CubeSats are mostly built by universities as educational and science missions, as part of NASA's Educational Launch of Nanosatellites program to attract students in science, technology, engineering and mathematics disciplines.

But NASA just sent two of them to Mars with its Insight lander, relaying data from the mission back to Earth, Haken said, "proof that CubeSats are a really useful thing to have around with bigger missions," she said.

The CubeSats are built of standardized cubes, 10 centimeters on a side, that can be strung together, Lembeck said. Their weight and other features are also standardized so that they can be launched on many different rockets, Haken said.

"What's unique about what we do at the university is that everything — all the design, all the structures — are all put together and designed by our students. We start from scratch," Lembeck said.

The UI lab has four other CubeSats lined up to launch in coming months. The next to go in April will be "SASSI," carrying a spectrometer to measure different kinds of chemicals in the upper atmosphere, which will help future spacecraft engineers design better materials for re-entry, he said.

Next October, the CAPSat will test three technologies developed at the UI, one designed to offset vibrations from the satellite to allow sharper imaging; another to dissipate heat that builds up inside the small satellite; and a third that would repair crystals used in quantum communication that are damaged by the sun, a technology banks are interested in to send encrypted information via satellite.

A third launch will carry several experiments from the UI and other universities. And the Space ICE mission, planned for 2020, will include an experiment developed at Northwestern to study freezing of materials in orbit.

Lembeck, who is finishing his first semester at the UI, previously worked at NASA and in private industry and plans to expand the UI lab as part of a major renovation at Talbot.

He said the educational part of the project is the most valuable component of the NASA-funded program, regardless of the outcome of the flight.

Haken started working in the lab the summer before her freshman year at the UI and said it taught her "just about everything I know."

"I've learned a lot about how the space industry works, I've learned a lot about how satellites work, all of the systems that you need in order to make them successful, and how the CubeSat community works," said Haken, who hopes to earn a master's degree in aerospace engineering at the UI and work for NASA someday.

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