" As shown in this video, a door latch and a pair of pliers are among the mechanisms created without screws, bolts or other fixings by researchers working with metamaterials. The team at the Hasso Plattner Institute's Human Computer Interaction Lab design objects that move despite being 3D printed as one single part. Specifically, the objects have controlled directional movement, which means they can perform set mechanical functions, like gripping something or latching a door. This makes it an example of a metamaterial – an engineered material defined by its internal structure rather than what substance its made of. Metamaterials have properties not found in nature, as with the real-life "invisibility cloak". The Hasso Plattner Institute's research opens up new possibilities for 3D printing by cutting out the need for a printed mechanism to be assembled from multiple, sometimes fiddly pieces. "The ultimate vision is to design the inside of objects," ...