By creating a new printing process which utilizes what MIT has dubbed “printable hydraulics,” the team hopes to facilitate a breakthrough in rapidly fabricating operational machines. Concerning the process itself, the researchers used an Inkjet 3D printer capable of dispersing bits of material that measure roughly half that of a human hair. While printing structures, the printer places photopolymer material on surfaces of the print and hardens them with a UV light, leaving liquid portions of the project untouched.
“Building robots inevitably involves the time-consuming and labor-intensive step of assembling a large number of discrete pieces,” MIT’s paper reads. “3D printers offer a way forward … However, until now there has been no means of incorporating robust, high-performance force-transmission elements directly into a 3D-printed part.”
After much trial and error, the team found a suitable liquid/solid combination allowing for the creation of a functioning robot in one print. Specifically, the print produced a six-legged robot capable of walking via the power of 12 hydraulic pumps printed inside it. All told, the entire print process lasted roughly 22 hours and once it concluded, the group fitted a motor and battery into its hexabot which allowed it to then move on its own.
Aside from the robot itself, the group also tinkered around with printing soft materials capable of lifting fragile objects. Similar to the 3D-printed movable legs native to the robot’s body, these soft arms can also be controlled via the printable hydraulics, allowing MIT to install sets of sensitive grabbers to the robots during the same session. Moving forward, MIT expects to improve on its innovative new method in order to dramatically cut down the amount of time required per print.