The ‘e-skin’ can sense pressure and temperature, and self-repair if someone cuts it
Our skin is a big part of what makes us feel alive. Would we consider ourselves to be living, breathing bodies if it weren’t for the pliable organ that keeps our organs from falling onto the sawdust? Would we be human if we didn’t meet the world with our skin-caked nerve endings?
We may be one step closer to giving this essential sense of touch to machines, thanks to efforts from the University of Boulder to create a malleable “electronic skin”, which is also able to self-heal if it’s damaged.
In a paper published today in the journal Science Advances, researchers detail the creation of an e-skin that encompasses sensors able to measure pressure, temperature, airflow and humidity. It’s built around a covalently bonded dynamic network polymer, known as polyimine, laced with silver nanoparticles to provide better conductivity and mechanical strength.
The use of polyimine allows the e-skin to be fully recyclable – something its creators note is important in the context of the millions of tonnes of electronic waste generated every year. The polymer can also self-heal if it’s cut by applying a slight amount of pressure. I’m told by co-author of the study Jianliang Xiao that this process usually takes less than half an hour at room temperature, but can be reduced at slightly higher temperatures.
“The e-skin can be applied to any place that requires sensation of the environment, such as prosthetics, smart textiles, space suits, and robotics,” Xiao explains. “It could also provide health monitoring to structures and human bodies.
“For robotics, it might not be very necessary to integrate e-skins with industrial robots to provide sensing capabilities at this point. But for robots that physically interact with humans, e-skins are very important to provide sensing and feedback of touching, holding and monitoring.
“Imagine a robot that can gently hold a baby, touch him/her like the parents do, and feel the temperature increase if the baby gets a fever,” he adds.
Imagine indeed. The team says further research will aim to improve the mechanical and electrical properties of the e-skin, optimising the flexibility, recyclability and self-healing for a range of different applications. If they manage to scale their efforts, it could very well herald a new conception of robots with sensing, healing ‘skin’, and bring them one step close to parity with fleshy humans.
Image credit: Jianliang Xiao / University of Colorado Boulder