High Performance Amphibious Light-Driven Soft Actuators Realized by Biomimetic Superhydrophobic Micropillars

Abstract

Light-driven amphibious soft actuators have been a research focus in soft robotics for their superior environmental adaptability and remote controllability. However, achieving amphibious motion in millimeter-scale light-driven soft actuators remains challenging, as designing and fabricating land-water compatible structures is difficult. In this study, we develop femtosecond-laser-fabricated tilted superhydrophobic microstructures to enable amphibious capabilities in soft actuators. Tilted micropillar-integrated superhydrophobic microstructures enhance land friction differentials and induce aquatic Marangoni effects, enabling inchworm-like crawling and water strider-like swimming in soft actuators. Benefited from that, the amphibious mobility of soft actuators has been realized compared to those without micropillars. The crawling speed on land is increased by ∼100%, while the swimming speed on water is increased by ∼60%. Compared with existing amphibious soft actuators, the proposed strategy is simple, nondamaging, and can enhance the motion performance, showing great potential in the amphibious applications of soft robots.