USC Professor Creates Robots to 3D Print Buildings

Future cities may now rise in a matter of months, we learned this week at Corenet Global's big annual conference on disruptive innovation at the LA Convention Center in Los Angeles.

Among the speakers was USC professor Behrokh Khoshnevis, who developed a breakthrough in robotic construction technology called contour casting, which makes anything architects can dream up possible to build quickly at a fraction of today’s costs. (Click here to check it out.)

This innovative technology, which builds structures layer by layer, is basically 3D printing scaled up to building size, Behrokh says. 

Behrokh, who has worked to perfect this technology for more than a decade, says he hopes his technology will radically change the world for the better. He would like to see it used to ensure everybody, including the nearly 1 billion people living in the world’s slums, has safe, dignified housing.

The technology’s potential applications are far-reaching. If adopted by the build industry, he says, 400,000 worker injuries or deaths could be prevented and billions of dollars in labor and material costs saved. For instance, walls are hollow, so less concrete is used, and buildings with domed roofs don’t require beams. It also reduces construction waste, uses minimal energy and has low CO2 emissions.

Robotic technology speeds up construction dramatically. The machines, which are light and easily transported to job sites, construct one square foot in 12 seconds. A custom-designed, 2,500 SF house can be built in about 20 hours or whole neighborhoods in a matter of weeks. Rapid construction time also would minimize construction loan costs, as projects that now take six months or longer could be built in days or weeks.

The process involves depositing cementitious material, initially concrete, through a nozzle that builds structures layer by layer (yes, "cementitious" is in the dictionary, and we still don't know what it means).

Reinforcement, plumbing and electrical network installation can be done as walls are rising, Behrokh says. When the basic structure is completed, other processes, including finishes, tiling and even painting also can be done automatically—the later using a printer similar to those used to print billboards, he says.

Machines can be reconfigured for different building shapes and sizes, from a single level to high-rises, with multi-nozzle machines that can climb tall buildings used to speed large project construction.

Robotic technology could make buildings seismically safer than those done with traditional construction. Behrokh says that building strength (illustrated) is the result of both design and materials used.

Time has proven that buildings with curved walls, for instance, withstand earthquakes better than buildings with diagonal walls. Because changing designs is simply a matter of changing software, a building can take any shape.

This allows architects unprecedented aesthetic and structural design freedom, uninhibited by practical issues like cost or lack of craftsman skill. Additionally, Behrokh’s patented nozzle is calibrated for high-performance, 10,000 psi concrete mixed with composite, fibrous material. 

Although robotic construction technology has not yet entered the mainstream build industry, LA-based Hyperloop plans to use it to construct the 9,000 pylons needed for building the track for California’s $68B high-speed train.

NASA has also adopted Contour Casting to build on Mars, things like landing pads, roads, hangars, housing, laboratories and manufacturing. Behrokh points out that only the equipment would need to be transported through space, because the technology can take advantage of raw materials found on the Red Planet. The US military also plans to use this technology to replace canvas field tents and medical facilities with concrete bunkers.