Artificial Robotic Muscles That Flex On Command

Artificial Robotic Muscles

Science Robotics published a study about a team of scientists in South Korea that has developed robotic muscles that can move when an electrical current is passed through them. Muscles contract and relax in order for humans to move. However, robots typically depend on motors and gears to move. In the recent past, researchers have been developing actuators to produce motion in robots. Using a stimulus such as electricity, the actuator contracts, expands and rotates like muscle fibers. An actuator should basically respond quickly to stimuli, bend without breaking and be durable. Scientists at the Korea Advanced Institute of Science and Technology (KAIST) developed a very responsive, flexible, thin and durable artificial muscle, in this study. The actuator is about an inch long and looks like a skinny strip of paper. It is made of a material called MXene—a class of compounds that have layers only a few atoms thick. Their chosen MXene material (Ti3C2Tx) is made of thin layers of carbon compounds and titanium. Initially it was not flexible by itself; when bent in a loop, sheets of the material would flake off the actuator. To change that, MXene was ionically cross-linked to a synthetic polymer. Still maintaining strength and conductivity, the combination of materials made the actuator flexible, which is critical for movements driven by electricity. It was demonstrated by the researchers that their actuator responded very quickly to low voltage, and lasted for more than five hours moving continuously. To prove that the artificial muscle works, the team included the actuator into wearable art: an origami-inspired brooch shaped like a narcissus flower that unfolds when a small amount of electricity is applied. Robotic butterflies were also designed that move their wings up and down, and made the leaves of a tree sculpture flutter. “Wearable robotics and kinetic art demonstrates how robotic muscles can have fun and beautiful applications,” was said by Professor Oh Il-Kwon a lead paper author and professor of mechanical engineering at KAIST. “It also shows the enormous potential for small, artificial muscles for a variety of uses, such as haptic feedback systems and active biomedical devices.” The team of scientists also plans to look into more practical applications of MXene-based soft actuators and other engineering applications of MXene 2D nanomaterials. Read more from Asian Scientist Magazine.