"Current self-healing materials have shortcomings that limit their practical application, such as low healing strength and long healing times (hours)," the researcher report in today's issue of Nature Materials. The researchers produced high-strength synthetic proteins that mimic those found in nature. Like the creatures they are patterned on, the proteins can self-heal both minute and visible damage. "Our goal is to create self-healing programmable materials with unprecedented control over their physical properties using synthetic biology," said Melik Demirel, professor of engineering science and mechanics and holder of the Lloyd and Dorothy Foehr Huck Chair in Biomimetic Materials. Robotic machines from industrial robotic arms and prosthetic legs have joints that move and require a soft material that will accommodate this movement.
The BBC's Circular Economy series highlights the ways we are designing systems to reduce the waste modern society generates, by reusing and repurposing products. This week we look at the prospects for hi-tech materials that can heal themselves. You don't have to be a liquid metal cyborg assassin from Terminator 2 to know that the ability to self-heal can be pretty useful. After all, our bodies do it all the time, so what if our phones, prone to cracks and scratches, could do it too? In January, tech giant Samsung filed a patent for an "anti-fingerprinting composition having a self-healing property" and there's been speculation that such a coating might give its next smartphone the S10, which comes out in early 2019, the ability to self-heal small scratches too.
Existing soft actuators have persistent challenges that restrain the potential of soft robotics, highlighting a need for soft transducers that are powerful, high-speed, efficient, and robust. We describe a class of soft actuators, termed hydraulically amplified self-healing electrostatic (HASEL) actuators, which harness a mechanism that couples electrostatic and hydraulic forces to achieve a variety of actuation modes. We introduce prototypical designs of HASEL actuators and demonstrate their robust, muscle-like performance as well as their ability to repeatedly self-heal after dielectric breakdown--all using widely available materials and common fabrication techniques. A soft gripper handling delicate objects and a self-sensing artificial muscle powering a robotic arm illustrate the wide potential of HASEL actuators for next-generation soft robotic devices.
Along with super-human strength and the ability to look great in chrome, robots can now add another talent to their box of tricks: self-healing. Roboticists have long aimed to use soft flexible materials, but these have a propensity to break making them unfit for purpose. A new technique can create soft robots that heal themselves when things go wrong. To prove the concept, researchers at the Free University of Brussels (VUB) in Belgium created a gripper, a robot hand and an artificial muscle, all with the ability to self-heal, out of rubbery polymers that look a bit like jelly. When ripped or cut they can knit back together completely.
A "smart" polymer cast that automatically seals itself around a broken arm, a membrane that can sense where it has been cut, and pneumatic actuators that can be cut and reconfigured into different shapes are some possible applications for a new self-healing material developed at Carnegie Mellon University. The composite material has unique characteristics that allow it to heal and make it possible for devices made from it to regain their functionality -- or gain new functionality -- after being cut. When the cut ends of the material are placed back together, the pieces reconnect and the seam between them eventually disappears. The research team, led by Lining Yao, assistant professor in the Human-Computer Interaction Institute (HCII), and Mohammad Islam, professor in the Department of Materials Science and Engineering (MSE), have demonstrated the material's self-healing qualities by building a variety of sensors and actuators. And they are working on new applications that enable devices to self-assemble and self-actuate.