Scientists create water-resistant electronic skin for robotic applications

Scientists have created a self-healing electronic skin inspired by jellyfish, that could be used in to develop a range of devices from water-resistant touchscreens to aquatic soft robots. The material, developed by researchers from the National University of Singapore (NUS) and the University of California, Riverside in the US, can self-heal in aquatic environments just like a jellyfish.

Researchers identified key obstacles that self-healing electronic skins have yet to overcome.

“One of the challenges with many self-healing materials today is that they are not transparent and they do not work efficiently when wet,” said Benjamin Tee from NUS. “These drawbacks make them less useful for electronic applications such as touchscreens which often need to be used in wet weather conditions,” Tee said.

They succeeded in this endeavour by creating a gel consisting of a fluorocarbon-based polymer with a fluorine-rich ionic liquid. When combined, the polymer network interacts with the ionic liquid via highly reversible ion-dipole interactions, which allows it to self-heal.

“Most conductive polymer gels such as hydrogels would swell when submerged in water or dry out over time in air. What makes our material different is that it can retain its shape in both wet and dry surroundings,” Tee said.

The electronic skin is created by printing the novel material into electronic circuits. As a soft and stretchable material, its electrical properties change when being touched, pressed or strained. “We can then measure this change, and convert it into readable electrical signals to create a vast array of different sensor applications,” Tee said.

“The 3D printability of our material also shows potential in creating fully transparent circuit boards that could be used in robotic applications. We hope that this material can be used to develop various applications in emerging types of soft robots,” said Tee.

Soft robots, and soft electronics in general, aim to mimic biological tissues to make them more mechanically compliant for human-machine interactions. In addition to conventional soft robot applications, this novel material’s waterproof technology enables the design of amphibious robots and water-resistant electronics.

“Millions of tonnes of electronic waste from broken mobile phones, tablets, etc. are generated globally every year,” said Tee, adding, “We are hoping to create a future where electronic devices made from intelligent materials can perform self-repair functions to reduce the amount of electronic waste in the world.”