It’s Alive: Electrically Charged Soft Robots

Embedded copper ions bring hydrogel soft robots to life when electrified.

Researchers at North Carolina State University have created a new method for animating soft robots, a burgeoning field in robotics.

In a recently published paper in Nature Communications, scientists detailed a method for embedding copper ions in a hydrogel structure, creating a substance that can be animated if electrified.

Key to the new technique are the properties of  hydrogel, a material that is almost, but not entirely, pure water, with a water content of 99.9%. Because hydrogel is filled with negatively charged ions, researchers injected positively charged copper ions throughout the hydrogel structure, in a process they call “ionoprinting.” With its new conductive skeleton in place, an electrical current could be run through the hydrogel, animating the material and transforming it into a “robot.”

According to assistant professor Michael Dickey, “This work brings us one step closer to developing new soft robotics technologies that mimic biological systems”.


Aside from soft robotics, the ionoprinting technique could have applications for biomedical fields. Since hydrogel – being water – is a biocompatible material, artificial muscles armed with sensors, actuators, and other devices could be created with the technique. In fact, Dr. Orlin Velev, professor of Chemical and Biomolecular Engineering at NC State, already has designs for the ionoprinting method. “We are currently planning to use this technique to develop motile, biologically compatible microdevices”.

In the future, biomedical implants and devices like Dr. Velev’s might not only be able to help regulate our body’s current performance, but enhance it as well.

Watch A Video of the Ionoprinting in Action:

Image and Video Courtesy of NC State