Stretching Electronics Give Circuits Healing Power

Carnegie Mellon University researchers develop self-healing material for soft electronics.

The seeds of discovery often come from the desire to make things easier for humans. Sometimes, innovation happens because non-human elements are given human-like abilities. The ability to repair oneself tops the list.

The automotive industry has tires that can self-inflate if they go flat and metals that can bounce back after a ding. Other research focuses on creating concrete that can fill its own cracks. Mimicking the self-healing ability of humans is about to go robotic. Researchers from Carnegie Mellon University recently announced the creation of a soft-matter material which can create soft, stretchable electrical circuits that instantly repair after sustaining extreme mechanical damage.

A clock continues to be powered even when circuitry is removed thanks to a self-healing material that can maintain a current when damaged. (Image courtesy of Carnegie Mellon University.)

A clock continues to be powered even when circuitry is removed thanks to a self-healing material that can maintain a current when damaged. (Image courtesy of Carnegie Mellon University.)

“If we want to build machines that are more compatible with the human body and the natural environment, we have to start with new types of materials,” said Carmel Majidi, an engineer at Carnegie Mellon University who directs the Integrated Soft Materials Laboratory.

The researchers found that the technology of stretchable electronics is a key component for progress in wearable computing, soft robotics and inflatable structures that use soft materials such as elastomers, polyelectrolyte gels and liquid metal. The downside to these is their vulnerability to tears, punctures and mechanical damages that can cause electrical failure.

Their solution was to create a composite material consisting of liquid metal droplets suspended in a soft elastomer. If damage occurs, the droplets instantly rupture to form new conductive pathways with nearby droplets and reroute electrical signals. The spontaneous self-repair means no manual repair or external heat is needed. In addition to self-healing, the material continues to conduct electricity, allowing it to maintain power and transmit data while fixing itself.

“A robot is very complex and difficult to repair, and the soft robots are particularly susceptible to sharp objects and high pressure,” said researcher Brad Vanderborght. “This research is the first step in introducing self-healing materials in soft robotics, which we think will start a whole new research field of self-healing robotics.”

Stretchable electronics have the potential to assist in various industries and could be used in many ways, such as to build a structure that could withstand Mars’ environment, to create robots able to enter dangerous situations without worrying about damage or to monitor and transmit health data as a medical tool.

Interested in more innovative materials? Check out Biomimicry-Inspired Surface Can Harvest Water from the Air and Self-healing Metal Oxides Could Protect Against Corrosion.