Enhanced functionality through dynamic effects of magneto rheological elastomers

Magneto-rheological elastomers (MREs) are composite elastic materials that undergo large deformations when subjected to magnetic fields. Structural mechanisms made of MREs have been exploited as actuators in fields ranging from microfluidics to soft robotics. To facilitate the design cycle in these classes of systems, several structural theories for magneto-active beams, rods, plates, and shells have recently been proposed. However, these existing modeling frameworks mostly focus on time-independent magnetic fields. Dynamic effects resulting from time-varying magnetic fields are rarely considered. Here, we investigate an experimental system to explore the dynamic response of an MRE beam under oscillatory magnetic driving. We characterize the dynamics of the structure, including its damping characteristics, as a function of the driving parameters. The gathered understanding is then leveraged to design an MRE bistable actuator that can snap through with a tunable critical load. We believe our results will inform the development of more efficient actuation mechanisms for MRE structures.