Engineers develop a self -made muscle for robots

Engineer Eric Markick, together with graduated students Ethan Krings and Patrick McManigal, recently presented an article at the IEEE international conference about robotics and automation in the Atlanta in the Georgia State, which sets access to a soft robotics level that can recognize the damage from the delusion and autonomous position.

The work was among the 39 of the 1,606 applications selected as the finalist of the best ICRA 2025 paper paper.

The team strategy can help overcome the long -standing problem in developing soft robotic systems that import the principle of design of inspired by nature.

“In our community, there is a huge pressure to replicate traditional solid systems using soft materials and a huge movement towards biomimicry,” said Markkvicka, Robert F. and Assistant Professor Myrna L. Krohn Biomedicine Engineering. “Although we were able to create stretch electronics and actuators that are soft and conformous, they often do not imitate biology in their ability to respond to damage and then start self-administrative repair.”

In order to fill that gap, his team developed an intelligent, self-recessed artificial muscle that contains a multi-layered architecture that allows the system to identify and find damage, and then start a self-adoption mechanism without external intervention.

“The human body and animals are amazing. We can cut and bear and get some rather serious injuries. And in most cases, with very limited external bends and medicines, we are able to complain many things,” Markkvicka said. “If we could repeat it in synthetic systems, it would really transform the field and how we think about electronics and machines.”

Tim “muscle” – or an actuator, a part of a robot that turns energy into a physical movement – has three layers. Lower part – a layer of detection of damage – soft electronic skin is made up of microdroplets of liquid metals embedded in silicone elastomer. This skin adheres to the middle layer, just healing the component, which is a rigid thermoplastic elastomer. At the top is the activation layer, which drives the muscle movement when under pressure.

To begin with the process, the team induces five currents to control over the lower “skin” of the muscles, which is associated with a microcontroller and a sensitive circle. Punching or pressure damage to this layer triggers the creation of an electrical network between traces. The system recognizes this electrical trace as evidence of damage and then increases the current that undergoes the newly formed electrical network.

This allows the network to function as a local Joule heater, turning the energy of electricity into heat around the area of ​​damage. After a few minutes, this heat melts and switches the middle thermoplastic layer, which seals the damage-inch the wound healing.

The last step is to reset the system back to its original state by deleting an electric trace of damage to the lower layer. To do this, the Markkkin team exploits the effects of electromigration, a process in which the electric current causes migration of metal atoms. The phenomenon is traditionally viewed as a obstacle to metal circles, as moving atoms deform and cause defects in circle materials, which leads to a malfunction of the device and fracture.

In great innovation, researchers use electromigration to solve a problem that has long plagued their efforts in creating autonomous, self -healing: seemingly stability of electrical networks caused by damage in the lower layer. Without the ability to reset the basic trace of monitoring, the system cannot fill more than one cycle of damage and repair.

She has achieved researchers that electromigration-Sa, with her ability to physically separate the metal ions and start a malfunction of the open circle-can be the key to deleting the newly formed traces. The strategy has acted: a further increase in electricity, the team can cause mechanisms of electromigracy and thermal failure that reset the network to detect damage.

“Electromigration is generally considered a huge negative,” Markkvicka said. “It is one of the narrow throats that prevented the miniaturization of electronics. Here we use it in a unique and really positive way. Instead of trying to prevent it from happening, we used it for the first time to delete the traces we thought they were permanent.”

Autonomous self -healing technology can revolutionize many industries. In agricultural countries like Nebraska, it could be a benefit of robotics systems that often encounter sharp objects such as twigs, thorns, plastic and glass. This could also revolutionize wearable health monitoring devices that have to withstand daily wear.

Technology would also use a wider society. Most electronics based in consumers have a life span of just one or two years, contributing to billions of pounds of electronic waste every year. This waste contains toxins such as lead and alive, threatening the health of human and the environment. Self -healing technology could help stop the tide.

“If we can start creating materials that are able to go through and autonomously detect when the damage occurs, and then we start these mechanisms of self-administration, it would really be transformative,” Markkicka said.