In the coming months, we’ll be running a series of articles based on the Lab’s 100 Urban Trends glossaries. Each week, our writers will focus on a trend that is meaningful to them, sharing anecdotes, opinions, and real-world illustrations of urban issues that shape our lives. Today’s trend: 3-D Printer.
3-D printers as we know them today have changed the world of design by allowing for rapid, on-the-spot prototyping and one-off manufacturing of small-scale objects. But what if 3-D printers could go big, and do much more than that? What if they could actually print the city?
That may not be as far off as we might think. If all goes as planned, Contour Crafting, an automated, robotic construction technique currently in the works in the engineering laboratories of the University of Southern California, will soon allow houses, skyscrapers, even highways in space to be 3-D-printed in a matter of hours.
Behrokh Khoshnevis, director of the Center for Rapid Automated Fabrication Technologies at USC began experimenting with large-scale 3-D printing techniques back in 2004. “One major problem with these processes these days is the speed. Plastic injection can be done in a few seconds, for example. A plastic cup comes out of the mold in less than ten seconds, maybe. But it would take a few hours to build the same plastic cup using 3-D printing, because we’re building layer by layer, and the layers are very thin. If you increase the layer thickness, you lose surface definition,” he says.
By adding a trowel to the side of a 3-D printing device, however, he discovered he could print thicker layers, while maintaining a smooth surface. Khoshnevis began experimenting with new materials, such as plaster, clay and, eventually, cement. “That’s basically when the whole project changed direction. I built a concrete structure and I thought, well, this could be the wall of a house,” he says. Et voila, the dream of a twenty-four-hour 3-D printed house was closer to reality than ever before. It has since become CRAFT’s mission, and it doesn’t seem to be too far off: though Khoshnevis and his colleagues have so far only manufactured parts of houses within the Lab’s walls, they expect to roll out a deployable device by the end of this year.
Khoshnevis’ visions for this technology are enormous. They start with the rapid construction of emergency, low-income, or commercial housing. His presentations show how the technology could be programmed to insert the same structural reinforcement elements as traditional building, such as rebar, as well as plumbing. It could also execute design methods currently not possible with the human hand, such as honeycombed wall interiors. But his dreams are even bigger than that. As the device is designed to climb the structure it is building as it builds, it could theoretically even be used to construct skyscrapers, and Khoshnevis is currently working with NASA to develop a model that could actually be used to build infrastructure on the moon and Mars.
The implications of this new technology could be enormous: drastically lower construction costs at a drastically quicker pace, with fewer workplace hazards. On the other hand, of course, such benefits would come with downsides, such as fewer manual-labor-based jobs, to start. In other words, Khoshnevis’ work could fundamentally change architecture and construction as we know them. The question seems to be whether or not we will let it happen. Are we ready for buildings squeezed from a tube?
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Photos: courtesy Behrokh Khoshnevis