|Aerospace Students Set For Wild Ride on NASA Jet
From: University of Cincinnati Currents
Date: February 25, 2000
By: Chris Curran
Phone: (513) 556-1806
Cincinnati A group of aerospace engineering undergraduates has been selected to fly a microgravity experiment as part of NASA's March 2000 Student Flight Campaign.
Their adviser, associate professor Trevor Williams and UC Professor David Richardson, are trying to understand how to make "nanosatellites" fly in formation up in Earth's orbit. NASA is exploring the idea of replacing large, bulky satellites with multiple, smaller satellites. Nanosatellites, by definition, only weigh a few pounds.
"The traditional way was to fly one big satellite with enormous antennas on it, but if you have a launch failure or a problem, you've lost your whole mission," said Williams. "A series of small satellites can fly in formation and collaborate. They can do the same mission as one huge satellite, but it's much cheaper to build them and if you lose one, you only lose one out of a whole bunch."
Flying in formation in low-Earth orbit isn't that simple, however. Satellites tend to get tugged out of position over time, so there has to be an effective method for occasionally adjusting their place in space.
The UC undergradaute experiment will test two different techniques. The experiment is being designed and built by a group of seven students who competed successfully to earn a spot on the special NASA flight. Four will actually go through intense training and fly on a KC-135 jet nicknamed the "vomit comet." The plane swoops up and down in roller-coaster fashion over the Gulf of Mexico, simulating the effects of zero gravity.
The students who will fly are Paul Zomkowski, Zoe Ruedele, Eric Riedle, and Michael Volle. Other team members are Bryce Smith, Karl Thal and Scott Estridge. Zomkowski is the team leader, and he explained the high-flying experiment actually has some very humble beginnings.
"We'll have a piece of plywood mounted to the aircraft floor with a structure mounted on top of that to hold a laptop computer," said Zomkowski. "Our 'satellite' is a ten-inch cube attached by a tether to the board."
The control mechanisms being tested are both relatively simple and rely on the slight air resistance present in low-EArth orbit. The control mechanisms have to be simple, because traditional systems such as fuel-guzzling thrusters are both too bulky and too expensive for nanosatellites.
"We're hoping to demonstrate that it works, and that it's not going to throw off the satellite when it's in orbit around the Earth. We'll actually be able to control it," said Zomkowski.
In a kind of "Goldilocks" analogy, a good control mechanism would send the prototype satellite spinning, but not too much or too little. It has to be "just right."
While the students are making their final adjustments and undergoing NASA training later this month, Trevor Williams will be at a scientific workshop with his collaborators from the Air Force Institute of Technology presenting plans for a future experiment to be conducted in space itself. Williams is also working with collaborators at the University of Surrey in England.
The undergraduate experiment is set to fly during the week March 6-11 from Ellington Field near the NASA-Johnson Space Center in Houston. Results from that will help Williams and his collaborators decide what components to include in their space-based experiment.
Funding for the nanosatellite research comes from a $400,000, multi-year grant from the Dayton Area Graduate Studies Institute (DAGSI).