Will your next home be built by robots?
Researchers hope to extend the manufacturing revolution to construction, but the building industry is proving set in its ways.
Author Steven Keating poses for scale inside of a half-dome autonomously printed by a newly developed robotic arm.
Courtesy of Keating, et al.
Imagine: At the push of a button a team of machines jumps into action, taking a digital blueprint and transforming an empty lot into one with a physical home in just days. They finish on time, on budget, and with zero waste.
This Jetsons-like vision of an automated future has come largely true for car manufacturing. Now engineers hope buildings will be next. From Apis Cor鈥檚 3-D printed house to the MIT Media Lab鈥檚 , startups and research teams alike aim to spark a digital revolution in an analog industry that has thus far proved resistant to听disruption.
In a California parking lot last July,听a 50-foot wide, 12-foot tall semi-domed structure arose over just two days, as a a robotic arm mounted on self-driving, tank-like treads spent 13.5 hours depositing layer after layer of plastic foam until it ballooned into a giant yellow beehive.听MIT hopes its (DCP), which it presented in the journal Science Robotics in April,听will lay the foundation for future buildings.
鈥淲e鈥檝e seen huge, huge advances through digital processes for the design side,鈥� says lead author Steven Keating. 鈥淏ut we haven鈥檛 yet really seen that translate to the construction site.鈥� Despite the alleged dawning of the , builders still build much like they did before the first one: stacking rectangles, sometimes by hand.
Construction is a massive industry, consuming听 than any other and accounting for . It's inefficient, too: construction produces half of all US solid waste, which makes it a prime target for the precision that robotics offers.
Yet construction sites, unlike indoor assembly lines, lie at the mercy of Mother Nature. And we rely on buildings for our safety far more than we do most other other consumer products.听
As such, the construction industry has proven understandably reluctant to innovate, explains Dr. Keating in a phone interview. 鈥淭hey have to be worried about structures standing for 50 to 100 years. Lives are at stake.鈥�
Still, some groups think they鈥檝e made a breakthrough.听In February, recent startup Apis Cor鈥檚 robotic arm built up layers of quick-drying concrete into the walls of what it calls the听. Completing the $10,000 model house took one month, including wiring and finishing, and printing the walls took one day, according to spokesperson Konstantin Nefedev.
It鈥檚 easy to see the technology鈥檚 allure. Printing walls allows builders to accurately predict the time and materials needed, which could bring down costs. Indeed, the University of Southern California is developing the similar听 with the explicit goal of making housing affordable for millions of people in developing countries.
But technology is just one part of the equation. 鈥淭here are several obstacles 鈥� the first being construction codes and regulations,鈥� writes Mr. Nefedev in an email. Russian testing facilities have certified Apis Cor鈥檚 concrete as being able to withstand multiple freeze/thaw cycles, but MIT鈥檚 Dr. Keating wonders how eagerly the safety-conscious industry will adopt materials that haven't proven themselves with decades of use.
Keating prefers technologies that buttress, rather than replace, the current methods. 鈥淏aby steps is how we can actually start to change the industry. If you鈥檙e doing it all from the ground up in one giant leap, it鈥檚 very difficult to integrate with existing construction worksites鈥� techniques.鈥�
Instead of going straight for erecting a whole building with novel materials, MIT chose to construct听a mold suitable for pouring regular concrete as their proof of concept, a method that is backward-compatible with .
鈥淚f you can come in and replace one key step, which is making that formwork, which defines the entire building鈥檚 geometry, you鈥檙e already using a system that鈥檚 widely used in construction. That鈥檚 how you can maybe get some actual real structures built and scale very quickly,鈥� explains Keating.
The robotic arm鈥檚 flexibility unshackles cost from form, opening the door to the strength of curvy buildings. 鈥淚f you look in nature, have you ever seen an animal or insect that has a square-shaped shell?鈥� he asks.
Keating鈥檚 also quick to point out that the demo showcases just one feature of the DCP: 鈥淚 want to emphasize that we don鈥檛 call this a 3-D printer. This is a platform.鈥� Like a human hand, its functions are tool-expandable, and currently include site excavation, cutting, surface finishing,听and welding chain links into stiff rods.
Alexander Schreyer, a professor of building technology at the听University of Massachusetts, Amherst, agrees that 3-D printing could bring welcome efficiency gains, but suspects it will never be a one-size-fits-all solution.
鈥淚n construction you鈥檝e always had a mixture of techniques,鈥� he says in a phone interview. 鈥淩ather than saying 鈥業鈥檓 going to 3-D print an entire house,鈥� I think a combination is ultimately a really good approach.鈥�
Mr. Schreyer says developments are already underway in the form of prefabricated parts : 鈥淚t鈥檚 like putting an Ikea piece of furniture together: it just fits.鈥�
Such techniques are readily available, but their lack of widespread popularity suggests that innovation in construction may face barriers besides technology and regulation.
鈥淲e all live in houses that have roughly the same functionality and roughly the same aesthetic. Why on Earth should every house have to be re-thought from the ground up?鈥� asks Schreyer.
鈥淭he car industry produces some things in mass and customizes just enough so that people are happy. It鈥檚 mind-boggling that that doesn鈥檛 happen with houses,鈥� he continues. 鈥淚鈥檓 assuming it can only be perception.鈥� People may assume prefabricated buildings are less durable, he speculates.
Ultimately, economics may force innovation. Despite the vast sums of money involved, the industry faces margins in the . Any method that offers a path to profit will handsomely reward companies who adopt it, but Schreyer suggests none has hit that tipping point yet.
Whether the houses of the future are cast, printed, or prefabricated, experts agree that change is coming, albeit gradually. 鈥淚 think the world will become more automated, and that includes construction, but I think it鈥檚 going to be a lot slower than people expect,鈥� says Keating.
In that sense the construction may resemble concrete itself, with its imperceptible but unstoppable flow. 鈥淲e all move in a single general direction,鈥� says Nefedev, about MIT鈥檚 DCP. 鈥淎ll technologies are progressing in incremental steps 鈥� whether it be a step or a leap forward, only time and practice will tell.鈥�