A research team at the Max Planck Institute for Intelligent Systems (MPI-IS), in collaboration with Koç University in Istanbul, has introduced a new method for reprogramming the magnetisation profiles of soft robots in real time and in situ. The approach, published in Nature, enables shape transformations without changing the external magnetic field, marking a departure from conventional magnetic robots, which typically rely on fixed magnetisation patterns.
The researchers, led by Metin Sitti of the Physical Intelligence Department at MPI-IS, developed a soft robotic structure composed of multiple nested tubes, similar in configuration to a Matryoshka doll. Each tube contains magnetic units that can be individually pre-programmed. By altering the configuration of the nested tubes through non-magnetic actuation—such as sliding the tubes relative to each other—the combined magnetisation profile of the structure can be dynamically changed.
This capability allows the robot to deform in one, two, or three dimensions while the magnetic field remains constant. For instance, a tube can shift from a straight line to a helix, or switch deformation modes in real time, depending on the reconfiguration of the stacked magnetic units.
The research team noted that this method may enable new approaches in areas requiring precise control of soft robotic structures, including potential applications in biomedical devices. One such application could be in catheter-based procedures for vascular treatment. Conventional catheters can cause friction and damage to blood vessels, particularly in older patients. A catheter with a reprogrammable magnetisation profile may reduce such risks by adapting its shape to the curvature of vessels in real time, potentially decreasing tissue damage and improving recovery outcomes.
The study’s first author, Xianqiang Bao, explained that the original objective was to create a method for altering magnetisation profiles dynamically. During the process, the team also identified additional features such as shape retention and magnetic neutralisation. Co-authors Fan Wang and Jianhua Zhang stated that future research will focus on integrating the method into specific applications and evaluating its effectiveness in different domains.
Photo credit MPI-IS
