Magnetic fields unlock soft robot control

Various structures for so-called soft robots, generally based on gels, have been fabricated in recent years. However, controlling these structures has always proved problematic, because of their necessary lack of stiff skeletons to which actuators can be attached. Researchers at North Carolina State University have now unveiled a new approach to soft robot control, employing magnetic fields as a means of moving the parts of the structure.

Soft robots have many potential applications, including manipulating delicate materials and structures in industrial processes and manufacturing, and as parts for assistive devices to help movement in disabled people and to boost workers’ physical strength. The North Carolina team is building on previous work by Prof Orlin Velev of the University’s Chemical and Biomolecular Engineering Department and material scientist Joe Tracy.

The researchers mixed microparticles of iron into a liquid polymer mixture and then applied a magnetic field to the polymer to draw the microparticles into aligned parallel chains. These were fixed into position by allowing the liquid polymer mixture to dry out, leaving an elastic film.