Soft robotics use robots made from non-rigid materials, such as silicone, rubber, and other compliant materials. Making them move has always been challenging and difficult. Recently, however, a team of scientists developed a new way of making them move through the use of directed magnetic field.

In order to create the mechanism, the scientists mixed together iron microparticles to liquid polymer. After that, the scientists let the liquid mixture dry and become a thin strip of elastic polymer embedded with the iron particle chain. When magnetic field was applied to the thin elastic strip, the iron chains inside it aligned themselves and moved along with the magnetic field.

Joe Tracy, author of the paper and an associate professor of materials science and engineering at NCSU, said that by embedding the self-assembling chains inside the soft robots, they were able to achieve complex actions through simple architecture.

Through the method, the scientists were able to create three different types of soft robots. The first one is like an accordion-type that flexes and emulates the movements of a muscle. The second-type can lift something that is 50 times its own weight and the third one functions like a peristaltic pump.

By using the magnetic field, the scientists were also able to control the soft robots remotely. Tracy said that once the technique is refined, possible uses would be remote deployable materials and triggered pumps that will deliver drugs.

The scientists said that they were also able to develop a metric fort assessing how magnetic lifters perform. The metric includes measuring the weight of the object being lifted, the mass of particles in the robot, and the amount of magnetic field being applied.

The research builds on Tracy's previous work on self-assembling, magnetic nanoparticle chains which Tracy collaborated with Orlin Velev, the INVISTA Professor of Chemical and Biomolecular Engineering at NC State.