Magneto‐Responsive Bistable Structures with Rate‐Dependent Actuation Modes

AbstractStructural instabilities can be used to provide rapid responses activated by mechanical force or displacement thresholds. The emergence of responsive materials has opened the door for adapting such structural instabilities to actuators that will abruptly deform guided by external stimuli. However, fast configurational transitions between equilibrium states imply important viscoelastic roles at the material level that inevitably scale up to the structural level. A comprehensive understanding of viscoelastic effects is provided on bistable structural transitions combining a new experimental perspective and a thorough modeling analysis. The insights from these results are here translated to magneto‐responsive bistable structures offering a route‐map to design effective actuation conditions. The bistable transition functionally depends on the combination of magnetic field amplitude and application rate. The understanding of the viscoelastic and magneto‐mechanical coupling provides efficient actuation via temporal magnetic pulses, removing the need of generating continued magnetic fields. Finally, these insights are combined to develop a responsive structure whose transient and steady bistable transitions can be modulated by the application rate of external magnetic stimuli.