Sound Idea: Georgia Tech Research Shows Radio Waves Could Build Settlements in Space

Large, massive structures could be built in space simply by using radio waves that create force fields to move materials and assemble them into various structures. Once bonded in place, the structures could lay the groundwork for human settlement in space and a space-based economy, according to Narayanan Komerath, an aerospace engineer at Georgia Tech.

A large number of objects can be arranged into shapes to form structures in reduced-gravity environments using radio and electromagnetic waves, according to Komerath, who is a professor in Georgia Tech’s School of Aerospace Engineering. The structures could range from micrometer-scale discs to kilometer-scale habitats.

Komerath recently presented his team’s work in Atlanta during a conference of the NASA Institute for Advanced Concepts (NIAC), which explores ideas that could potentially result in funding from NASA. The team, which named the project “Tailored Force Fields,” found that structures could be built in small, enclosed gas-filled containers using sound waves. But in the vacuum of space, electromagnetic waves could be used.

“The development of a comprehensive space-based economy is the best way to achieve the goals of human exploration and development of space,” Komerath said. “In such an economy, humans would gradually find more reasons to invest in space-based businesses and eventually to live and work in space for long periods, interacting for the most part with other humans located in other space habitats.”

Concepts for extracting materials and power from the Moon and asteroids are already being developed. But Komerath says the idea of using force fields could solve some of the long-term problems of inhabiting space, such as the construction of a massive shield to protect humans from radiation, the danger and expense of humans laboring in space and skepticism about the prospects for building an economy in space.

According to Komerath’s idea, robotic craft would be sent to Earth’s asteroid belt to break up an asteroid into small pieces. Formations of satellites would follow and form a radio-wave resonator that would begin moving the debris into various structures. Komerath estimates that it would take approximately one hour to form a rubble cloud into a 50-meter long enclosed structure, and could hold for another 12 hours while the pieces are fused together.

Sound Waves as Construction Machines

The idea follows earlier flight experiments conducted by the team that tested the effects of intense sound on a variety of particles in near-zero gravity conditions. Results from the technique – called “acoustic shaping” – proved the basic theory that sound waves could form raw material into walls of specified shape.

These experiments have been performed inside rectangular boxes containing various materials including Styrofoam pieces, porous grains, aluminum oxide spheres and aluminum spheres. These experiments have been performed on the ground and aboard NASA’s KC-135 Reduced Gravity Flight Laboratory.

Komerath says that light is already used in microscopes to hold nanosized particles and microwaves could shift millimeter-sized material, but radio waves would be needed to move brick-sized stones. An engineer by training, Komerath admits that such a concept sounds alien to most engineers, who are taught to think “faster, lighter and smaller” as well as “cheaper and better” for anything related to space.

Komerath’s findings were gathered after a six-month feasibility study funded by a grant from the NIAC. Komerath estimates that a demonstration experiment could be ready for space flight by 2009.

The Georgia Institute of Technology is one of the world's premier research universities. Ranked seventh among U.S. News & World Report's top public universities and the eighth best engineering and information technology university in the world by Shanghai Jiao Tong University's Academic Ranking of World Universities, Georgia Tech’s more than 20,000 students are enrolled in its Colleges of Architecture, Computing, Engineering, Liberal Arts, Management and Sciences. Tech is among the nation's top producers of women and minority engineers. The Institute offers research opportunities to both undergraduate and graduate students and is home to more than 100 interdisciplinary units plus the Georgia Tech Research Institute.