Contour Crafting, a technology NASA's eyeing for off-planet housing, is a robotic extruding method. Like smaller 3D printers, the “printer” head follows designs from CAD software. The printer uses cement or a plaster/polymer mix, and designs can be customized while work is underway.
The machines can also automatically embed electrical, plumbing and air-conditioning conduits, and place electronic sensors to monitor a building's temperature and health, says Behrokh Khoshnevis, professor of industrial and systems engineering at USC's Viterbi School of Engineering.
Khoshnevis, who is leading the effort to perfect Contour Crafting construction, believes 3D printed buildings will address the problem of population growth; the technology -- which Khoshnevis expects to be commercially viable within two years -- could finish a house's shell in a day.