Thin-Film-Shaped Flexible Actuators

Abstract

Human-like and creature-like systems are one of the most representative imaginary blueprints of future robots. To fulfill this blueprint, the development of high-performance actuators across different length scales is indispensable. Owing to their mechanical compliance and conformability to curvy surfaces of living organisms, flexible actuators have emerged as an essential direction of next-generation actuators. This review focuses on thin-film-shaped flexible actuators (TFFAs), a rising family of flexible actuators, aiming to provide an overview of the state-of-art status in this exciting direction. The designs, manufacturing, and mechanisms of various TFFAs are summarized, according to their key composing materials/mechanisms, including, for example, nanomaterials, liquid crystal elastomers, shape memory polymers/alloys, hydrogels, biohybrids, and other mechanisms/materials. The representative applications of TFFAs are introduced, ranging from biomedical uses, robots for environment explorations, to haptic interfaces and reconfigurable electronics. Finally, the grand challenges and open opportunities are discussed in detail.