3D printing has been great and has made headlines from 3D printed guns to Yahoo Japan launching a 3D printing search engine to basic daily objects like 3D printed toothbrush. The revolution 3D printing will have in the manufacturing industry is only limited by the imagination. To add to the potential of 3D printing, the US Military has given $385,000 to researchers at the University of Pittsburgh Swanson School of Engineering, Harvard School of Engineering and Applied Sciences and the University of Illinois to research on 4D printing.

The military wants the research team to develop a 3D printer that can print objects in 4D (that would be a 4D printer, right?). The 4D printing means that objects printed will be able to change shape, form, and/or colour with time according to the environment, circumstances or/and as per user needs. CNET explains that 4D printed objects will be able to change its colour and patterning, or alter its structure to adapt to changing environmental conditions. As explained by SJET.US, “4D Printing entails multi-material prints provided by the Connex Technology with the added capability of embedded transformation from one shape to another, directly off the print-bed”.

The ability to create one fabric that responds to light by changing its colour, and to temperature by altering its permeability, and even to an external force by hardening its structure, becomes possible through the creation of responsive materials that are simultaneously adaptive, flexible, lightweight and strong. It’s this “complicated functionality’ that makes true 4D printing a game-changer,” said the University of Illinois’ Dr Ralph G Nuzzo.

Given the military funding, we can only imagine what they want achieved through 4D printing technology. Do they want to make objects (robots) that appear as fragile only to harden at attack? Or spyware that can change colour and pattern according to the environment? Think of robotic spies that can flow as liquid or harden as a wall according to circumstances. Already the military is working on Iron Man’s suit that can change from liquid to solid within milliseconds.