Researchers Create the World’s Smallest Walking Robot

In partnership with the U.S. Army, Cornell Univ. researchers are designing foldable robots on the nanoscale. These tiny structures — including the world’s smallest paper crane — could revamp modern robotics by enabling easy locomotion, as they need just a jolt of electricity to fold and move.

“The foldable robots emerge from two dimensions into three dimensions much in the same way that origami shapes do,” says Dean Culver, a researcher at the U.S. Army Research Laboratory. “You take a material that’s very thin, so thin that it can be creased, and designate where those creases can occur. The creases are where the magic happens. If you can control the contraction of one side of a 2D strip, the strip will bend inward to where the contraction occurs. This can be done chemically, optically, or electrically.”

To get thin, two-dimensional materials to bend and fold, Cornell scientists have developed micron-sized shape memory actuators. These devices change their molecular orientation in response to voltage and hold their form without continuous power. In many cases, electricity causes the shape memory actuator to expand or...