Researchers at the Ulsan National Institute of Science and Technology in South Korea have developed an innovative magnetic composite artificial muscle. Compared with traditional artificial muscles, the new material can withstand more than 1,000 times its own weight, and is expected to bring more powerful robotic arms to robots, wearable devices, etc. The paper was published in the new issue of Nature Communications.
Flexible artificial muscles, which mimic the smooth movement of human muscles, have become a popular technology in many fields such as robotics, wearables, and biomedicine. However, traditional artificial muscles are often not rigid enough and have unwanted vibrations, making it difficult to lift heavy objects and maintain precise control.
To overcome this bottleneck, the researchers combined ferromagnetic particles that generate enormous magnetic force with a shape memory polymer made of a multifunctional rigid material to create a new soft magnetic composite artificial muscle with significantly improved load-bearing capacity and elasticity.
According to the researchers, through a unique surface treatment method, a complex physical tangle is formed between the ferromagnetic particles and the shape memory polymer. This synergy not only enhances the mechanical properties of the composite, but also allows it to respond quickly to external magnetic fields.
The test results showed that the new artificial muscles showed extraordinary adaptability, with 2,700 times more stiffness and more than 8 times more flexibility. Under rigid conditions, it can withstand tensile stresses up to 1,000 times its own weight and 3,690 times compressive stresses.
To mitigate the effects of external vibrations, the researchers also used a two-layer structure, one of which was a hydrogel. This design allows the artificial muscles to be precisely controlled during rapid operation.
According to the researchers, the mechanical properties and flexibility of this new artificial muscle surpass that of existing artificial muscles. Using a variety of methods, such as laser heating and magnetic fields, they can remotely control artificial muscles to perform basic movements such as elongation, contraction, flexion and twisting, as well as more complex movements such as precise manipulation of objects.