Liquid Crystal Elastomer Actuator Matrix for Large Area Applications

ABSTRACT In recent years, main‐chain liquid crystal elastomers (LCEs) have been of widespread interest in soft robotics research. LCEs are polymer resins that can be molecularly aligned and show large contractions upon application of various stimuli. A current challenge is the fabrication of large‐scale soft actuator arrays while addressing individual actuators. Here, we describe a scalable method for the fabrication of flexible foils with thermally driven active LCE elements, enabled by controlled Joule heating of a resistive heater array. Four different heater designs were made on two different polymer foil types. Electrothermal properties, power consumption, and the resulting actuation behavior were investigated and characterized. By combining conventional thin‐film electronics processes for the manufacturing of heaters with direct ink writing of the LCE, a matrix of 25 elements was realized that produces local on‐demand actuation at low power, i.e. down to a 2 mm bending radius at below 400 mW per actuator. The scalable thin‐film electronics fabrication in combination with printed LCEs shows potential for applications in texture‐changing surfaces or surface‐driven object motion, examples of which include haptic displays or soft touch human‐machine interfaces.