Artificial Muscle Developed in South Korea Can Lift 4,000 Times Its Own Weight!

Seoul: In a remarkable scientific breakthrough, researchers in South Korea have developed an artificial muscle that can lift nearly 4,000 times its own weight, paving the way for more powerful and flexible humanoid robots.

The study, conducted by scientists from the Ulsan National Institute of Science and Technology (UNIST), has been published in the journal Advanced Functional Materials. The team claims that this is the first time an artificial muscle has been designed with the ability to switch between soft and rigid states depending on need — a feature that closely mimics real biological muscles.

Professor Hoon Eui Jeong, the lead author of the study, said,

“Our research removes a fundamental limitation of traditional artificial muscles, which were either highly stretchable but weak, or strong but rigid. Our composite material can do both, making it ideal for use in soft robots, wearable devices, and intuitive human–machine interfaces.”

Artificial muscles are considered transformative because they are lightweight, flexible, and can move in multiple directions. The challenge, however, has been achieving high work density (the amount of energy output per unit volume) without sacrificing stretchability.

The newly developed material — described as a high-performance magnetic composite actuator — combines complex polymers and magnetic micro-particles that work together to replicate the contraction and relaxation of real muscles. One of the polymers used can change its stiffness dynamically, while the magnetic particles embedded on the surface allow external control of movement and rigidity.

The researchers incorporated two distinct cross-linking mechanisms in their design:

Covalently bonded chemical networks – where atoms share electrons for a stable structure.

Reversible physical interaction networks – which allow flexibility and durability.

This dual-structure design gives the artificial muscle long-term endurance and adaptive motion capabilities, potentially revolutionizing robotics and assistive technologies in the years to come.