A robotic arm designed for spacecraft repair and maintenance will be put to the test next week in a near-weightless environment -- along with some of its Cornell student designers.

Cornell's Control Moment Gyroscope (CMG) Research Team, comprising graduate and undergraduate, mostly mechanical engineering students, is one of 34 school teams selected by NASA for this year's Reduced Gravity Student Flight Opportunities Program. The space agency invites students to experiment with engineering devices and principles aboard an aircraft that creates a near zero-gravity environment.

The CMG team, recently named Student Project Team of the Year by the Cornell Engineering Alumni Association, has created a robotic arm powered by gyroscopes, devices consisting of a spinning wheel on an axle. The arm will accompany the students aboard the NASA aircraft affectionately known as the "Vomit Comet" because of its reputation for inducing motion sickness.

Aboard their two scheduled flights May 3 and 4, the students will test, and hopefully prove, their theories about the arm's power efficiency and agility. Yet to be named, it stands about a foot off the floor and weighs 63 pounds. The CMG team has spent many afternoons carefully assembling its parts, wiring its electrical power sources and tweaking its design to withstand a weightless environment. According to the students' calculations, their gyroscopic robotic arm can operate at 90 percent better efficiency than would a similar arm using conventional power sources.

A CMG is a type of motorized gyroscope that produces high torque for very little power. Though the devices are commonly used to control the orientation of spacecraft, the students have instead employed the technology to make an arm that can manipulate objects. They designed it around two sets of gyroscopes connected to a power source that they salvaged from an old computer.

The current generation of space shuttle robotic arms -- such as the International Space Station's Canada Arm 2 -- are powered with more conventional sources, are relatively slow and drain power quickly, explained team co-captain Michael Stocke, M.Eng. '07.

"We're trying to use gyroscopes to actuate a similar type arm in order to increase the agility of the arm," said Stocke, adding that the arm is also designed to function with minimal human supervision.

As they prepare to travel to Houston April 28 for their flight, the student engineers hope that a successful demonstration at NASA may one day lead to commercialization of the concepts they will be demonstrating, such as the theoretical efficiency of the arm. "The objective is to verify that theory," said Mason Peck, assistant professor of mechanical and aerospace engineering and the students' faculty adviser.

Aboard the flight, the team will record how the arm performs, including how it responds to inputs, and its power consumption, said co-captain Joshua Kennedy, M.Eng. '07, who leads the weekly flight crew meetings.

"We have expectations on what it should do, but hopefully it'll just do what we tell it to do, and it if doesn't, then hopefully, we'll be able to back out our errors and fix it," Kennedy said.