Spatially programmable 4D printing of photoresponsive liquid crystal elastomers for adaptive energy dissipation

Liquid crystal elastomers (LCEs) offer a compelling platform for constructing intelligent soft systems via reversible shape transformation and mesogen-induced energy dissipation. Here, we present a spatially programmable 4D printing approach to fabricate photo-responsive LCEs architectures with tunable actuation and impact absorption characteristics. By encoding mesogens alignment through tailored extrusion parameters (speed, pressure, temperature, path geometry), we achieve localized molecular orientation for anisotropic photothermal deformation. This strategy allows monolithic LCEs structure to seamlessly integrate multiple deformation modes, including bending, twisting, and curling. Finite element simulations validate that mesogen orientation governs actuation strain, while programmable shape morphing governed by embedded stress anisotropy. Moreover, we demonstrate adaptive energy dissipation behavior through thermally modulated shape transitions, where printed LCEs structures transition from planar to dome under NIR light, significantly altering impact response. This work provides a design framework for multifunctional, stimuli-responsive materials in impact damping, soft robotics, and adaptive surfaces.