November 2004
Washington University in St. Louis
Washington University CubeSat readied for NASA/Air Force competitionSatellite as small as a cantaloupe docks with medicine ball-sized mothershipFailure at a university is a word with bad connotations, unless you are involved in building experimental satellites that the U.S. Air Force and NASA find interesting.
An aerospace engineer at Washington University in St. Louis who works with students building experimental spacecraft says student-built spacecraft, which he calls "university-class," have a strong advantage over aerospace industry-built spacecraft: the freedom to fail.
"Experimental failure is a basic element of university life, and from the university perspective a failed spacecraft is not necessarily a failed mission," said Michael Swartwout, Ph.D., Washington University assistant professor of mechanical and aerospace engineering.
"Students still learn from the mistakes, and no one is hurt by the failure. What universities can do for space science and engineering is tackle new or risky concepts � whether new technologies or different ways of operating spacecraft -- and demonstrate a concept that might be used for a bigger spacecraft some day. This puts the risk on the student-side as opposed to Boeing, for instance, sinking millions of dollars into a dubious program."
Swartwout said there has been a boom in spacecraft production at universities worldwide, with 30 university-built spacecraft launched over the past decade. Enabling this trend has been the electronics revolution of the late '90s, which made possible the opportunity for universities to make much smaller vehicles with much cheaper price tags. This in turn led to Swartwout developing the modus operandi of developing student-built, "disposable," spacecraft that function over a short timeframe of a few weeks.
The hope, Swartwout said, is that some day an innovation developed by students at a university will become a "disruptive" technology � one that is implemented and alters the status quo of spacecraft design. He might have such a disruptive technology at Washington University in Bandit, a satellite not much bigger than a cantaloupe.
Swartwout presented a paper on the future of university-class satellites at the 18th annual AIAA/USU Conference on Small Satellites, held Aug. 9-12 at Utah State University, Logan, Utah.
Bandit is similar in size to the hottest technology class in spacecraft design, CubeSats. These tiny payloads usually weigh no more than two pounds, with their electronics occupying several inches of space. While CubeSats are self-sufficient crafts, Bandit depends on a mothership for recharging its batteries and communications. Swartwout oversees the construction of Bandit, which over the past two years has benefited from the sweat equity of about 60 students. Currently, a dozen students are putting the finishing touches on Bandit, with 12 others in different university classes having some input.
Bandit's outstanding feature is its ability to be launched and dock on another spacecraft, making it a prime candidate to serve NASA or the Air Force in an inspector capacity. The Bandit inspector, dock and flight electronics is less than six pounds and requires less than two watts of power, on average. Bandit is the lead experiment for Washington University's Akoya nanosatellite (about the size of a medicine ball, making it actually bigger than Bandit), a part of the Air Force Research Laboratory/NASA University Nanosat 3 competition. Using image-based navigation, Bandit will travel with Akoya, usually no more than 10 feet away from the mother ship, and docking on Akoya, recharging and leaving the mother ship to navigate on its own.
"Bandit is of high interest to NASA and the Air Force because they like the notion of small, automated spacecraft that can go out and do inspections of a shuttle or communications satellite," Swartwout said.
The Bandit concept was hatched three years ago by Washington University students in an introductory space engineering class who came up with the idea of a small satellite to be launched from a spacecraft and serve as a re-entry probe. It grew from that to its present status as a docking inspector. While most of Bandit's design has been the product of students, a Washington, D.C. based company, Planetary Systems, has provided some recent input.
In January 2005, three of Swartwout's students will travel to Reno, Nev., .as participants in a NASA/Air Force sponsored spacecraft design competition. If they win, the Washington University team will be assured of a spot on a future NASA space mission to test Bandit under real conditions.
Swartwout said that the track record for university- class CubeSats and Nanosats is roughly 50 percent successful for both. But, he stressed, failure is not a deterrent.
"Our primary product is the trained student," he said. "It's not much fun, but writing a failure report provides almost the same amount of learning as writing a successful mission report. Employers would rather see the student make the mistake now and learn from it than never encounter the problem and then make the mistake on the job. We do our best to make things work, but if they don't, there's still plenty to be learned."
First-year graduate student Jared Macke, of Swansea, Ill., has been Bandit's student project manager for the past three years. Bandit also has roots in the School of Engineering and Applied Science's Project Aria program. Project Aria is a Washington University education and outreach program designed to aid both engineering undergraduates and K-12 students.
Keith Bennett, adjunct assistant professor of computer science and engineering at Washington University, initiated the program and continues to oversee it with Swartwout's assistance. Project Aria allows K-12 students to participate in space and space-related projects. Over the past several years, Project Aria has allowed K-12 students to send experiments aboard the Space Shuttle and participate in remote exploration programs. Previous K-12 projects include the Aria-1, Aria-2, Aria-3, and Aria-4 Space Shuttle packages. Arias 5-8 are awaiting future shuttle flights.
"Over the past two years interest in Bandit, our skills, and the number of students working on the program in the laboratory have steadily increased, "Macke said. "I have gotten to travel to, it seems, every corner of the United States to promote the Bandit program and Project Aria. I've gotten to attend satellite fabrication courses and design reviews of our work with Air Force/NASA personnel on several occasions. Just this spring I got to test the Bandit on NASA's reduced gravity simulating aircraft, the KC-135. Three of my fellow students and I got to experience NASA physiological training and weightlessness.
"Bandit really has become an interesting program to work on for undergraduates, grad students, and faculty. It's been great to see the project gain momentum and team members."
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