Fig. 4
From: Inverse design framework for 4D printed structures using the finite element method
Characterization and modeling of the electrically responsive EAP hydrogel. (a) Actuation mechanism: under an applied electric field, ion migration drives water transport, leading to nonuniform swelling and bending. (b) Five-layer simulation model of the EAP hydrogel with definition of the gradient swelling factor (GSF) (\(c_g\)) and a simplified assumption of linear dependence on time. (c) Schematic of the experimental setup for extracting \(c_g\), conducted under fixed conditions (20Â V, 90Â s, 25Â \(^{\circ }\)C). (d) Actual experimental setup used for GSF calibration and validation.
