On the magnetic actuation of accordion structures comprised of magneto-active elastomers

Magneto-active elastomers (MAEs) have garnered significant attention for their versatility in adaptive structures and soft robotics. This study investigates the behavior of soft-and hard-magnetic MAE accordion structures under external magnetic fields, focusing on the effects of demagnetizing fields. To the best of our knowledge, the soft-magnetic MAEs have been employed in these structures for the first time. Three different configurations with two or four MAEs were examined: hardmagnetic structures with an initial angle of 0°, and softmagnetic structures with initial horizontal angles of 20°and 45°. Each structure was fabricated using a silicone base with MAE patches glued on it and tested under varied magnetic fields. The results reveal that hard magnetomagnetic structures exhibit uniform deformation with minimal rotational effects, while soft magnetic structures demonstrate significant angular rotation, flipping or downpressing at low starting angles due to demagnetizing field-induced torques. The 20°soft-magnetic configuration showed the most pronounced responses, emphasizing the influence of initial starting angle. This work contributes to the understanding of magnetic field interactions in MAE structures and provides a foundation for designing programmable, magnetically controlled actuators for advanced engineering applications.