A new artificial muscle has been developed which creates a path to self-healing robots.
An engineering team at the University of Nebraska–Lincoln, in the United States, say their work delivers a soft robotics technology that could identify damage from a puncture or extreme pressure, pinpoint its location and autonomously initiate self-repair.
Engineer Eric Markvicka said the team’s strategy may help overcome a longstanding problem in developing soft robotics systems that import nature-inspired design principles.
“While we’ve been able to create stretchable electronics and actuators that are soft and conformal, they often don’t mimic biology in their ability to respond to damage and then initiate self-repair,” Mr Markvicka said.
He said his team had developed an intelligent, self-healing artificial muscle featuring a multi-layer architecture that enabled the system to identify and locate damage, then initiate a self-repair mechanism — all without external intervention.
“The human body and animals are amazing. We can get cut and bruised and get some pretty serious injuries. And in most cases, with very limited external applications of bandages and medications, we’re able to self-heal a lot of things.
‘“If we could replicate that within synthetic systems, that would really transform the field and how we think about electronics and machines.”
Mr Markvicka said the team’s “muscle”, or actuator, the part of a robot that converts energy into physical movement, had three layers.
He said the bottom one, the damage detection layer, was a soft electronic skin composed of liquid metal microdroplets embedded in a silicone elastomer.
“That skin is adhered to the middle layer, the self-healing component, which is a stiff thermoplastic elastomer. On top is the actuation layer, which kick-starts the muscle’s motion when pressurized with water.”
Mr Markvicka said the researchers used electromigration to solve a problem that had long plagued efforts to create an autonomous, self-healing system i.e. the seeming permanency of the damage-induced electrical networks in the bottom layer.
Download the paper: Intelligent Self-Healing Artificial Muscle. Mechanisms for Damage Detection and Autonomous Repair of Puncture Damage in Soft Robotics.