With thousands of hours logged on the project over nearly two years, University of Colorado at Boulder students are approaching the finals in what has been referred to as the national championship series for satellite design, sponsored by the U.S. Air Force Office of Scientific Research.
CU-Boulder will be one of 11 universities participating in the AFOSR University Nanosatellite Program's Flight Competition Review Jan. 19-20 in Albuquerque, N.M. Only one of the participating schools is expected to have its satellite selected for launch as a secondary payload by 2011.
"A lot of schools undertake the building of satellites, but getting a launch opportunity for one of this magnitude is very, very rare," said aerospace engineering graduate student Bruce Davis, systems integration and testing lead for the CU-Boulder team. Other schools in the competition include the University of Texas at Austin, Texas A&M University and Penn State.
CU-Boulder won an earlier student satellite competition sponsored by AFOSR in 2002 with its Three Corner Sat project, a partnership with New Mexico State University and Arizona State University. The three schools won the right to launch two small satellites in December 2004, although their mission was cut short by a sensor glitch on the launch vehicle.
CU-Boulder's new project, called the Drag and Atmospheric Neutral Density Explorer, or DANDE, is an 18-inch spherical satellite designed to measure variations in the upper atmosphere that create drag on orbiting satellites. The area of study is the thermosphere, an area ranging from 60 to 300 miles above the Earth's surface, which is affected by solar storms and flares.
"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," said aerospace engineering graduate student Marcin Pilinski, project manager.
The project began in January 2007 with about 15 students, but the team more than doubled this fall to a total of 40 students, ranging from freshmen to Ph.D. candidates. The interdisciplinary team of aerospace, mechanical, and electrical engineers is advised by professors Jeffrey Forbes and Scott Palo of aerospace engineering sciences, and Chris Koehler of the Colorado Space Grant Consortium.
In addition to its strong scientific basis, the DANDE satellite is unique in this day and age because of its spherical shape, CU students say.
"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," Pilinski said. "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 and accelerometers that measure drag, and radio equipment to send data back to Earth in real time.
Team members, who have been working to integrate the various systems for the last six weeks, are looking forward to the competition with confidence, having already undergone a vibration test at Ball Aerospace and Technologies Corp. and a zero-gravity flight on NASA's KC-135 to test the satellite's separation system.
But they also are keenly aware of the tough questions they will face. "The judges are very experienced and they know where the linchpins are that hold a project together. Those who have gone through this before say it's like being fired out of a cannon into a herd of stampeding buffalo," Pilinski said.
Until then, students expect to work late many nights through January. Davis has been counting down the days remaining since before Thanksgiving. Major tasks still to be accomplished include assembly of the satellite's systems in the clean room and trouble-shooting software problems. All work is being done in the Discovery Learning Center at the College of Engineering and Applied Science.
"Two years may seem like a long time to some, but it was an incredibly short time frame for what the students had to accomplish," Palo said.
The AFOSR's 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. I would love to see this come full circle, to be able to build the satellite and also to collect the scientific data," Pilinski said.