Swelling-induced bending and pumping in homogeneous thin sheets
We realize steady curved shapes from homogeneous hydrogel flat structures which are in contact with two environments at different chemical conditions. We numerically investigate the behaviour of beam-like and plate-like structures during the transient state, which realize osmotic pumps. Through numerical experiments, we determine the relationship between the difference in the chemical potentials at the top and bottom of a beam and the curvature of the bent beam as well as the Gaussian curvature of a spherical cap morphed from a flat plate. We also propose an approximate modeling of both the beam and the plate, to evaluate explicitly that relationship and show the good agreement between those formulas and the outcomes of the numerical simulations.