With thousands of hours logged on their project over two years, University of Colorado at Boulder students had a lot on the line as they approached the finals in what some people have called the "national championship series" for satellite design.
CU-Boulder was one of 11 schools participating in the University Nanosatellite Flight Competition Review, held Jan. 19-20 in Albuquerque, N.M. Among its competitors were such large schools as the University of Texas at Austin, Texas A&M University, and Pennsylvania State University.
"We knew when we walked in, we were in the top three," recalls aerospace engineering graduate student Bruce Davis, explaining that the scientific concepts behind the CU-Boulder satellite were strong, the team's preparation thorough, and their documentation—including both microgravity and vibration tests—extensive.
Two days later, CU-Boulder emerged victorious, winning the coveted launch opportunity offered by the U.S. Air Force Office of Scientific Research (AFOSR).
"A lot of schools undertake the building of satellites, but getting a launch opportunity for one of this magnitude is very, very rare," explains Davis, who served as systems integration and testing lead for the CU-Boulder team. "The two biggest factors in our win, according to the judges, were our documentation and our workmanship."
Indeed, CU-Boulder's satellite, called the Drag and Atmospheric Neutral Density Explorer, or DANDE, is a thing of beauty. The 18-inch sphere is designed to measure variations in the thermosphere—an area ranging from 60 to 300 miles above the Earth—that create drag on orbiting satellites.
"Our goal is to have DANDE become a space weather station and help improve the scientific model that the Air Force uses to help track objects in space," says graduate student Marcin Pilinski, who served as project manager.
The satellite was built by about 40 aerospace, mechanical, and electrical engineering students, ranging from freshmen to PhD candidates. Aerospace engineering professors Scott Palo and Jeffrey Forbes, along with Chris Koehler, director of the Colorado Space Grant Consortium, served as advisers.
"Two years may seem like a long time to some, but it was an incredibly short timeframe for what the students had to accomplish," Palo says. "I'm still amazed that in that short time this went from a design on paper to a working piece of hardware."
The project was launched in January 2007 when CU-Boulder and 10 other schools were awarded $110,000 contracts from the AFOSR to design and build the nanosatellites they had proposed.
CU-Boulder students took on a difficult challenge in proposing DANDE. "It's easier and cheaper to build a rectangular satellite, but the study of drag in the atmosphere requires symmetry, so we thought it was important to design it as a sphere," Pilinksi says. "This created various other challenges such as how to attach flat solar cells on a spherical shape and how to design a structural mechanism to hold the satellite in the launch vehicle."
The satellite's solar cells power an onboard computer, an orientation control system, wind sensors, accelerometers that measure drag, and radio equipment to send data back to Earth in real time.
Twenty students, or about half the DANDE team, participated in the competition's final review. Each team was required to make a 15-minute presentation summarizing its project in front of all the other schools, and then to go through four judging rounds in which they demonstrated their satellite, incorporating documentation and other materials, to a total of 25 judges.
The judges met to discuss the projects at the end of the second day before the announcement of winners was made. Second place went to Washington University in St. Louis, and Michigan Tech took third.
"We are very proud of everyone, from the youngest undergraduate to the most experienced student on the team," Pilinski says, noting that each member of the CU-Boulder team was able to answer questions about all aspects of the project, even those they had not worked on themselves.
Palo agreed: "I cannot tell you how impressed I am with the professionalism and quality of work completed by our students. It was truly amazing. The students were terrific ambassadors for CU, and the results of this competition continue to enhance our reputation as the place for space."
The University Nanosatellite Program attempts to balance two goals: designing and building an operational satellite that addresses the Air Force's strategic interests and developing the next generation of engineers and leaders in the aerospace industry.
"For young engineers, this is a great opportunity to be involved in a project over the long-term and to work on a team," says Pilinski. "I would love to see this come full circle, to be able to build the satellite and also to collect the scientific data."
Students plan to make some modifications to improve the satellite before delivering it to the Air Force by the end of 2009, with the expectation it will be launched as a secondary payload by 2011.