Ultra-light fabric muscles bring lifelike motion to wearable robots

Researchers at the Korea Institute of Machinery and Materials (KIMM) have developed ultra-thin fabric muscles made from shape memory alloy (SMA) coil yarn thinner than a human hair, enabling the mass production of lightweight, flexible artificial muscles for wearable robots. Using a novel automated weaving system, the team created fabric muscles capable of lifting 10 to 15 kilograms while weighing only 10 grams. Unlike traditional bulky and noisy actuators, these fabric muscles mimic human tissue flexibility, allowing natural, multi-joint motion and improved comfort for extended wear. The continuous production process was achieved by replacing the metallic core in SMA coils with natural fiber and redesigning the weaving machine and actuator structure, ensuring uniform, high-quality output critical for commercialization. Leveraging this technology, KIMM produced the world’s first clothing-type wearable robot weighing under two kilograms, which assists the elbow, shoulder, and waist simultaneously, reducing muscle effort by over 40% during repetitive tasks. They also developed an ultra-light shoulder-assist robot