Electrothermally Addressable Liquid Crystal Elastomer Microactuator Arrays with Integrated Microheaters

Liquid crystal elastomers (LCEs) are attractive for microscale actuation because they exhibit large, reversible, and programmable deformation. However, practical LCE microsystems remain difficult to realize due to challenges in fabricating discrete actuator arrays and achieving localized, electrically addressable actuation. Existing localized driving strategies often rely on optical stimulation, which is less practical for scalable integrated systems. In this work, we present an electrothermal LCE microactuation system enabled by lithographically integrated tungsten (W) microheaters. Surface-aligned LCE microactuators are integrated above dedicated serpentine heaters, and a column-addressable architecture is used to demonstrate selectively addressable actuation within a microarray. The heater voltage-temperature response is established through resistance-based calibration and incorporated into a finite-element electrothermal model, which is validated against measured sensor temperatures and then used to estimate the local temperature of the LCE units. Using separate device implementations with different programmed director configurations, the same electrothermal system design is demonstrated for elongation, contraction, bending, and twisting. The resulting deformations are interpreted using a temperature-dependent anisotropic eigenstrain framework. Actuation strains up to ~ 25% are achieved at 8 V, while neighboring non-addressed columns show less than 4% strain at the maximum driving voltage, indicating localized activation with limited thermal crosstalk. These results establish the feasibility of electrothermally addressable LCE microactuation and provide a practical basis for future integrated soft microsystems.