Programmable Multiresponse Marangoni Actuator Enabled by a PINPAM/MWCNT Composite Material

Inspired by natural organisms, actuators have shown great promise for small swimming robots. However, previous single-stimulus-driven studies have limited their effectiveness in complex aquatic environments. In this study, a PINPAM/MWCNT composite actuator was developed. This actuator can be controlled by both light and chemical agents to achieve rapid drift on the water surface. It enables programmable trajectory motion in water, capable of performing complex maneuvers such as linear translation, turning, and rotation, particularly under infrared light. Inspired by natural dovetail configurations, the movement and control of corresponding actuators can be achieved through chemical agent actuation. The horn-shaped actuator, modeled after natural horns, can propel and transport cargos under an infrared illumination. Notably, the circular actuator can spontaneously traverse a complex U-shaped curve without external stimuli. This multistimulus-responsive Marangoni actuator significantly broadens the application scope of miniature actuators, paving new avenues in microrobotics and inspiring future advancements in biomimetic robotics.