Spatially Hierarchical Gradient Orientation of Liquid Crystal Gels for Antagonistic Cooperative Actuation

Muscle-inspired soft actuators with high compliance and environmental adaptability hold significant potential for advancing miniaturization, autonomy, and intelligence in robots. However, conventional liquid crystal (LC) actuators are constrained by a chemically uniform anchoring environment, struggling to construct multidimensional programmable director gradients essential for complex deformation and locomotion. Here, we report a patterned nanoassemblies-engineered hierarchical gradient orientation strategy for fabricating seamlessly integrated antagonistic LC actuators through deliberately programming physicochemical anchoring environments for guiding the spatially gradient alignment of LCs. Owing to the enhanced orientational order, dynamically regulatable strain incompatibility, and mechanical heterogeneity over the film thickness, the obtained splayed LC actuators exhibit helical shapes with periodically evolving parameters, generating bidirectional reversible deformation modes of loosening and tightening that cover a broad adjustable range from -85% to 233%. Furthermore, these antagonistic actuations can be arbitrarily integrated into a monolithic system by precisely controlling the patterned orientational frameworks, facilitating the controllability of omnidirectional motions in both direction and placement, which is essential for navigation within confined spaces. This generic design principle opens a pathway for exploring stimuli-responsive materials with designable actuation for next-generation soft robots.