Shape-morphing systems can be found in many areas, including
smart textiles1
, autonomous robotics2
, biomedical devices3
,
drug delivery4 and tissue engineering5
. The natural analogues
of such systems are exemplified by nastic plant motions,
where a variety of organs such as tendrils, bracts, leaves and
flowers respond to environmental stimuli (such as humidity,
light or touch) by varying internal turgor, which leads to
dynamic conformations governed by the tissue composition
and microstructural anisotropy of cell walls6–10. Inspired by
these botanical systems, we printed composite hydrogel architectures that are encoded with localized, anisotropic swelling
behaviour controlled by the alignment of cellulose fibrils along
prescribed four-dimensional printing pathways. When combined with a minimal theoretical framework that allows us to
solve the inverse problem of designing the alignment patterns
for prescribed target shapes, we can programmably fabricate
plant-inspired architectures that change shape on immersion
in water, yielding complex three-dimensional morphologies.