Multistable mechanical metamaterials are artificial
materials whose microarchitecture offers more than two different
stable configurations. Existing mechanical metamaterials rely on
origami or kirigami-based designs with snap-through instability and
microstructured soft mechanisms. Scalable structures that can be
built from mechanical metamaterials with an extremely large number
of programmable stable configurations remain elusive. In a new
report now published on Science Advances, Hang Zhang and a research
team in engineering, electronics, and advanced structure technology
in Beijing China, used the elastic tensile/compressive asymmetry of
kirigami microstructures to design a class of X-shaped tristable
structures. The team used these constructs as building block
elements to build hierarchical mechanical metamaterials with
one-dimensional cylindrical geometries, 2D square lattices and 3D
cubic or octahedral lattices with multidirectional multistability.
The number of stable states increased with the cell number of
mechanical metamaterials incorporated in the work, and the
versatile multistability and structural diversity demonstrated
applications within mechanical ternary logic operators with unusual
functionalities.
Hierarchical mechanical metamaterials offer multiple stable
configurations
