It’s difficult to comprehend the boundless possibilities of 3D printing. It can make everything from guns to character costumes, and some even believe most people will have a 3D printer in their home by 2025. The next step in 3D printing is the ability to quickly print off all the robots that will eventually take our jobs.

But there’s a catch: 3D printing methods struggle with printing solid and liquid materials at the same time. Today, MIT’s Computer Science and Artificial Intelligence Laboratory (CSAIL) announced in a new research paper that it has a solution.

Researchers have developed a new, single-process method for printing hydraulic robots with a commercial 3D printer. The current 3D robot printing method usually consists of putting separately printed parts together by hand. This new one takes out the messy and time consuming act of humans inserting hydraulics into printed robot parts.

“Our approach, which we call ‘printable hydraulics,’ is a step toward the rapid fabrication of functional machines,” Daniela Rus, one of the research paper’s co-authors, told CSAIL. “All you have to do is stick in a battery and motor, and you have a robot that can practically walk right out of the printer.”

The demonstration video above is an example of a 3D-printed, six-legged, 12-pump hydraulic robot. What it lacks in size, it makes up for in innovation.

To make the robot, a 3D printer used a printing method that combines solid and fluid elements organized as support, flexible, rigid, and liquid from the bottom up. Each layer had a photopolymer section to be hardened into a solid, and a non-curing section meant to remain liquid. The printer then beamed solidifying UV light on the materials meant to be solid, and left the liquid stuff alone. It took 22 hours to make.

It’s a process that can be done with the same commercial 3D printer that’ll be in your home in the future. Best of all, the process spits out a finished product that needs no additional assembly.

Mark this achievement down as yet another hurdle cleared in the mission to simplify and cheapen the manufacturing of robots.

“The CSAIL team has taken multi-material printing to the next level by printing not just a combination of different polymers or a mixture of metals, but essentially a self-contained working hydraulic system,” Hod Lipson, Columbia University engineering professor and co-author of Fabricated: The New World of 3-D Printing, told CSAIL. “It’s an important step towards the next big phase of 3D printing — moving from printing passive parts to printing active integrated systems.”

Photos via CSAIL