It's the ultimate mash-up of high tech. Two designers at LA-based architecture firm Gensler have created a drone with an attached 3D printer that extrudes concrete. Designers Tam Tran and Jared Shier, Assoc. AIA, launched the project in 2013. It was one of 30 funded annually over a three-year period by Gensler's in-house research program, in which the firm invests 18 percent of its profits after taxes each year. They showcased their work at South by Southwest's Robot Petting Zoo in Austin this past March.
Their goal is to remove one of 3D printing's biggest limitations: the size of the print bed. By taking the technology airborne, the designers say, architects and engineers could one day create at an unprecedented scale as well as in areas where it would otherwise be difficult to haul construction materials or where a conventional, large-scale 3D printer isn’t practical.
“[We] were really frustrated about how the current 3D-printing technology is always limited to the build site,” Tran says. “So we asked a different question: What if we remove the printer box altogether and freed the printer head ... allowing it to print in any direction and also in any location?” The team looked into different types of robotic platforms and found the budding market for unmanned aerial vehicles, or drones, to be promising. “We thought the drone or some kind of flying vehicle would be able to give that freedom the most,” he says.
The result is MUPPette—short for Mobile Unmanned Printing Platform with the "-ette" suffix to signify its small size. The custom-assembled drone sports GPS sensors, a laser rangefinder for altitude control, as well as a novel 3D printer that the team 3D printed and attached to the unit complete with a gravity-assisted spiral conveyor whose open top allows for easy refilling. “You can basically call it a Frankenstein of parts that comes together to do what it does,” Tran says.
Though the pair hopes the printer will be able to extrude in a straight line and create layered shapes by this time next year, the project hasn’t come without its challenges. Among them, learning the ropes of two industries—the largely open-source 3D printing world and the fast-developing small drone market with its current dearth of formal regulations—as well as balancing time for research (20 hours each week) with the requirements of their day jobs at the firm (40 to 50 hours weekly).
Gensler subsidizes the research to help participants balance firm responsibilities and the new project, but Tran and his team have applied the money (Gensler couldn't disclose how much) almost entirely to parts and pieces. “Things break in crashes, things malfunction,” he says, before adding: “It’s a passion for us to explore this type of technology and learn more and also push the boundaries of it, that we didn't have a problem ... giving most of the money to parts versus time."
Perhaps most obvious is the challenge of turning an abstract idea into a product that actually works. The team initially explored extruding PLA plastic but found it too small and lightweight for their purposes and switched to concrete. "Since we never intended that MUPP would replace the desktop 3D printer, we moved forward with a heavier and thicker material that we are more familiar with: concrete," Tran says. That also means balancing payload and flight capacity. Currently, MUPP can fly for 20 minutes while carrying 10 ounces of material. "This is proof of concept," he says. "Hence we do not need to push flight and payload capacity since others in the community are [already] pushing those areas of development."
Instead, the pair is ironing out other technical issues. For example, during test trials the device’s mechanical vibrations caused the concrete to shake loose from the extrusion tube, dotting the ground below with gray clumps. They are now testing new technology and assemblies to stabilize the printer.
A fine-tuned prototype that shows the potential for this fabrication method—something the team is still working on—is only the beginning. "We're an architecture firm and we come up with amazing ideas and innovations and put it out there with the intent to push technology and innovation but ... we realize that this is now becoming more of an engineering feat versus a concept or an idea," Tran says. "We're hoping to partner up with anyone who is willing to advance the technology in that way."