Researchers from the Ulsan National Institute of Science & Technology (UNIST) in South Korea have achieved a breakthrough in material engineering by developing a magnetic composite artificial muscle that combines both skin-like softness and enough strength to handle heavy loads comparable to the weight of cars. According to UNIST’s findings, this adaptable material is 2,700 times stiffer than traditional soft materials, enabling it to provide both gentle and powerful movements as needed.
The UNIST team led by Professor Hoon Eui Jeong engineered this artificial muscle by combining two key elements: ferromagnetic particles and shape memory polymers. Ferromagnetic particles respond to magnetic fields, allowing the material to be remotely controlled. Meanwhile, shape memory polymers enable the muscle to adjust its shape in response to stimuli like heat or light and then revert back. This combination allows the artificial muscle to achieve both strength and flexibility—qualities often at odds in traditional materials.
To strengthen the bond between these two materials, researchers applied a specialized surface treatment, ensuring robust performance and efficient responsiveness. This bonding process improved the overall durability of the muscle and allowed it to achieve precise and controlled movements when exposed to a magnetic field. Jeong explained, “Utilizing multi-stimulation methods, including laser heating and magnetic field control, we can remotely execute fundamental movements such as elongation, contraction, bending, and torsion, along with more complex actions like manipulating objects with precision.”
With an incredible 90.9% of input energy converted into useful work, these artificial muscles display unmatched efficiency. Additionally, they are designed to handle tensile forces 1,000 times their weight and withstand compressive forces up to 3,690 times their weight. These impressive figures, paired with the muscle’s adaptability, make it ideal for applications where strength and responsiveness are essential.
To further enhance the functionality, researchers introduced a double-layer design featuring a vibration-damping hydrogel layer. This innovation minimizes vibrations, even at high speeds, allowing for steady and precise operation in high-performance environments.
The study was published in the journal Nature Communications.