Call it a match made for the heavens: MR SAT and MRS SAT, a pair of microsatellites created by UMR engineering students, will tie the knot before they launch into space.
The UMR students are working with NASA and industry representatives to develop the two microsatellites as an experiment in developing "distributed" space systems. Working with NASA’s Goddard Space Flight Center, the students hope their tethered satellite will become the space agency’s first satellite system to use a tether as short as 10 meters (33 feet).
UMR’s MR SAT Team, made up of 28 students from a variety of engineering disciplines, began working on the project in the summer of 2002. The team has created a model of both microsats, and now expects to spend another two years on the project before the system is ready for its trip into space.
When the project is completed, the students will have created two microsatellites — MR SAT (short for "Missouri-Rolla Satellite") and MRS SAT (for "Missouri-Rolla Second Satellite") — connected by a tether. The students hope NASA will use their creation to test new technologies for distributed space systems, or satellites that rely on "tight" formation flight to communicate with one another, just as flocks of birds fly in formation, says Dr. Hank Pernicka, a UMR associate professor of mechanical and aerospace engineering and advisor on the project.
The research also will allow NASA and the students to study satellite dynamics and develop low-cost wireless communications links between satellites.
The MR SAT project is partially funded by NASA and the University of Missouri Research Board. The Boeing Co. also is interested in supporting the project, Pernicka says.
"Our mission will test methods by which to fly spacecraft in formation," says Pernicka. "The MR SAT mission will involve the flight of two small satellites tethered to one another. The tether will be relatively short (about 10 meters) compared to those flown in the past."
The group of 28 students come from aerospace, computer, electrical and mechanical engineering disciplines. "It’s kind of an eclectic mix of students," Pernicka says. "We have some students who were enrolled in a core course for the project, as well as some graduate students and several student volunteers who just wanted to participate in the project."
One of those students, Matt Feldmeier, a senior aerospace engineering major from Wildwood, Mo., says the project teaches students many lessons they don’t necessarily learn in the classroom.
"The part about the project I enjoy most is the application of knowledge to solve real problems," says Feldmeier, the team’s chief engineer. "Also, the freedom to use innovative solutions — to really break the mold if you want — is a plus.
"But another aspect to engineers, especially aerospace people, is that satellites are pretty cool," Feldmeier adds. "Who wouldn’t want to get involved in something like that?"
Once completed and shot into space, the spacecraft will be monitored and controlled from a ground station on the UMR campus. Before their launch, the students will construct a prototype and test the system’s structure, software and hardware. The students have built a model of the satellite but are still in the design phase.
Formed as a cube of 45 centimeters on each side — or 18 cubic inches, roughly the size of a microwave oven — MR SAT is much smaller than the typical satellite. MRS SAT is even smaller, and will be designed to sit inside MR SAT when the two are launched.
The advantage of this type of spacecraft design, says Pernicka, is simply to keep satellites in proper formation. "It’s just like walking your dog on a leash," he says. "The spacecraft can’t wander away from each other." Once launched, the tether between the two satellites will extend and data will be collected from the dual-spacecraft "formation" created by the tension in the tether. Once the necessary data is recorded, the tether will then be cut and the spacecraft will record data separately. The two modes of operation will then be evaluated and compared in terms of their effectiveness for future space missions. Pernicka says the tether design makes this type of spacecraft different than past satellite designs. "Only a few missions to date have used tethers, and many of those have failed," he says. Data received from the satellite operation will be used to benefit future missions, including the development of innovative, low-cost spacecraft technologies. "We will also be testing a low-cost means by which the two satellites can communicate with each other," says Pernicka. "A wireless Internet-type transceiver will be used to accomplish this." The team also is experimenting with a welding method known as "friction-stir welding" to build the spacecraft. Pernicka hopes the spacecraft will be completed by the summer of 2006. The timing of an actual launch will depend on several factors pertaining to the schedule and priorities of the launch vehicle market, he says.
Members of the MR SAT Team are: