Mechanical Engineers Defy Gravity

PASADENA, Calif., and Cape Canaveral, Fl.--On the day that California Institute of Technology mechanical-engineering students will fling projectiles through the air in their annual design competition, two Caltech mechanical-engineering alumni will hurtle through space on the shuttle Endeavor.

The theme of this year's ME 72 Engineering Design Contest, the culmination of an engineering design laboratory for undergraduate students, is "fire and fly." It is fitting for a day on which astronauts and Caltech alumni Garrett Reisman and Robert Behnken lift off on the Endeavor space shuttle as part of a seven-man team en route to the International Space Station. The competition will be held on Tuesday, March 11, at 1 p.m. on Caltech's North Athletic Field, and the shuttle is scheduled for liftoff from Cape Canaveral, Florida.

Chris Brennen, Caltech's Hayman Professor of Mechanical Engineering, helped guide the ME 72 students through their test phases. He'll be at the shuttle launch on the day of their competition, but he remarks, "I was deeply torn between attending the space-shuttle launch and the ME 72 final contest." Reisman was his former student who became a close friend and married another mechanical engineering grad, Simone Francis.

Reisman, a space station flight engineer, will remain at the International Space Station for about six months and Behnken will return home after 16 days in orbit. A third Caltech alumnus, Greg Chamitoff, will then climb aboard Endeavor for the next launch, scheduled for March 28.

Brennen has close ties to NASA. He advised the agency on the shuttle's liquid-oxygen pumps and developed a lab at Caltech for creating and testing the main engine turbo pumps. When that facility was decommissioned several years ago, NASA disassembled it and moved it to the Marshall Space Flight Center in Huntsville, Alabama.

Brennen has spent much of his career investigating phenomena related to fluid flow, which he says was particularly useful in prepping students for ME 72 this year. "This year's ME 72 is different from previous contests because it involves some aerodynamics and fluid dynamics. It requires significantly more analysis of the mechanics of the device and the flight of the projectile in order to maximize the performance," he says.

On contest day, Brennen leaves the students in the hands of Joel Burdick, a professor of mechanical engineering and bioengineering at Caltech, who also helped them prepare. "We've had two contests already and tested and made adjustments. They're ready to go," Brennen says.

The competition centers on two basic constructions. The first is a ground-level launching device. The second is its 50-gram payload, "a projectile or flying device that will rise from a ground-level launcher, fly over a rope hurdle and then glide or be projected as far as possible over clear ground," according to the project description.

What happens after launch will be anybody's guess. In accordance with ME 72 tradition, the students may turn their machines on each other, navigating the airborne projectiles via remote control to tackle opponents' devices. According to the contest rules, "special admiration and an extra bonus" go to those payloads that land in a specially marked, two-meter-wide circular region beyond the basic target zone.

For further contest specifications, visit http://robotics.caltech.edu/~me72/. For more on Endeavor, go to http://www.nasa.gov/mission_pages/shuttle/main/.