Programming nonreciprocity and reversibility in multistable mechanical metamaterials

Abstract

Nonreciprocity can be passively achieved by harnessing material nonlinearities. In particular, networks of nonlinear bistable elements with asymmetric energy landscapes have recently been shown to support unidirectional transition waves. However, in these systems energy can be transferred only when the elements switch from the higher to the lower energy well, allowing for a one-time signal transmission. Here, we show that in a mechanical metamaterial comprising a 1D array of bistable arches nonreciprocity and reversibility can be independently programmed and are not mutually exclusive. By connecting shallow arches with symmetric energy wells and decreasing energy barriers, we design a reversible mechanical diode that can sustain multiple signal transmissions. Further, by alternating arches with symmetric and asymmetric energy landscapes we realize a nonreciprocal chain that enables propagation of different transition waves in opposite directions.

Magnetically Assisted Rotationally Multistable Metamaterials for Tunable Energy Trapping–Dissipation

“…[ 4 ] In addition, the attained bistability is usually associated with an asymmetric potential energy landscape and can be marginal such that the energy required to return the structure to its undeformed (initial) configuration is considerably small compared with the energy used to reach the deformed stable state. Although marginal bistability is beneficial in generating transition waves, [ 18,20–22 ] particularly to realize autonomous deployable structures, [ 23 ] it is usually not preferable in load‐bearable reconfigurable metamaterials since small disturbances may trigger undesired reconfigurations. Furthermore, the load–displacement relationship of multistable metamaterials composed of solely mechanical negative stiffness elements is not easily adjustable after the fabrication process, thus adversely affecting their tunability and adaptability to changing application requirements.…”

Mechanical nonreciprocity in a uniform composite material

“…One simple example is the realization of nonreciprocal transmission of the displacement field through the fabrication of silicon rubber into a fishbone-structured metamaterial ( 10 ). However, mechanical nonreciprocity has so far mainly been realized through the complicated design of active robotics ( 15 , 16 ) or metamaterial frameworks ( 17 , 18 ). Even the most advanced systems still rely on the shaping and connection of reciprocal materials, which limits the design freedom and practical applications of such systems.…”

Discriminative Transition Sequences of Origami Metamaterials for Mechanologic

“…Note that this process may become computationally expensive for an extremely complex multistable mechanical metamaterial. However, some mechanical metamaterials are made up of basic bistable unit cells via periodical connections in series or in parallel, for example, the multistable metamaterial based on bistable buckled beams, [ 5 ] Stacked Miura origami, [ 35 ] and Kresling origami. [ 25 ] For these examples, the number of stable configurations can be easily derived, that is , where N is the number of the constituent unit cells.…”

“…[3,4] Among these practices, the multistable metamaterials, which are fundamentally nonlinear in their constitutive profiles, are mainly operating in linear regimes within small deformations around different stable equilibria between configuration transitions. On the other hand, other prospects, such as nonreciprocal wave transmission, [5][6][7] impact energy trapping, [8][9][10] shock isolation, [11,12] and transition signal propagation, [13][14][15] have leveraged the nonlinear feature of global multistability, particularly the snap-through transitions among different stable configurations. Recently, there is a growing interest in harnessing multistability for mechanical logic gates [16][17][18] and mechanical memory devices [19,20] by correlating the mechanical configurations with their digital counterparts.…”