Concept and design of a metastructure-based multi-stable surface

Metastructures composed of snapping beams are capable of deforming into a series of stable states, enabling them to realize shape reconfigurations. In this paper, we present the design of a metastructure-based morphing surface that is able to exhibit a series of stable configurations with different curvatures. Using theoretical, numerical, and experimental approaches, we study the snap-through transition between the initially flat and the curved stable configurations. Effects of geometric parameters on the snap-through and curvatures are systematically investigated. Results show that the beam thickness is important for tuning the snap-through response, while the curvature can be tuned by changing the beam height and the horizontal span of the structures. Furthermore, an analytical model is developed to investigate the structural nonlinear deformations. It is shown that the proposed model can predict the snap-through transition properly. The structural stability can be controlled by setting proper values for t/L and h/L (t, h, and L represents the beam thickness, height and span, respectively). Finally, it is demonstrated that based on two-dimensional arrangements of bi-stable elements, various stable configurations, like corrugations in different directions, can be imposed to the surface.