Programmable Electroactive Bending Morphology of Cantilevered Dielectric Liquid Crystal Elastomer Sheets via Tuning Mesogen Alignments

The nematic mesogens within dielectric liquid crystal elastomers (DLCEs) rotate in response to external electric fields, thereby driving macroscopic active shape morphing. This work establishes a rigorous theoretical framework to investigate the electro-mechanical bending mechanics of cantilevered DLCE sheets governed by this actuation mechanism. By theoretically formulating the electromechanical effect as a localized spontaneous strain field, we analytically correlate the stress-free deformation with the local nematic director alignment. We demonstrate that the macroscopic bending morphology of the DLCE sheet can be deterministically programmed by tailoring the principal bending directions via this microscopic director design. Our findings reveal that the synergistic interplay between the tailored spontaneous curvature and cantilever boundary constraints generates a rich variety of three-dimensional configurations, enabling active regulation of both deflection and out-of-plane tilting at the free edge. Furthermore, we explicitly highlight the critical, yet often overlooked, role of spontaneous shear strain, which significantly governs the bending response even within the thin-plate limit. These theoretical insights establish a robust foundation for the structural design of DLCE-based directional soft actuators and flexible devices.