Facet-driven folding for precise control of hydrogel pore actuation

Microactuators driven by shape transformation achieve targeted functionality through tailored geometric designs. However, reliance on simplistic configurations restricts the understanding of deformation behavior and the versatility of adaptive systems. Here, we demonstrate geometrically guided actuation of hydrogel pores by controlling folding dynamics. Unlike non-faceted circular pores that exhibit randomized folding, hinges in faceted pores direct folding along predefined vertices, enabling control over the degree of constriction and restoration of the pores. By systematically designing key geometrical factors, such as the shape, dimensions, and spatial proximity to neighboring units, we effectively regulate shape transformation, aided by classical plate theory and finite element analysis. The resulting geometry-dependent adaptable topologies enable controlled entrapment and sequential release of microparticles, as well as information encryption through fine-tuned and localized pore actuation. This approach to adaptive micropore actuation controlled by facet-driven folding opens new possibilities for developing microactuators, particularly in applications requiring precise microobject manipulation.