A Rolling Light-Driven Pneumatic Soft Actuator Based on Liquid-Gas Phase Change

Light-driven wireless actuators provide obvious advantages for remote control. However, traditional double-layer actuators are restricted to the thin film deformation mode when undertaking complex tasks. Here, an actuator is proposed that employs thermal strain and local photothermal effects induced by low boiling point liquids to generate asymmetry along the fiber axis, thereby causing elastic deformation of the fiber. Under continuous irradiation, the sustained elastic deformation results in dynamic frustration within the fiber, creating torque around its axis. Based on this principle, the fiber actuator fabricated in this study enables rolling translation, while the ring actuator achieves simultaneous rolling and lifting motion for object manipulation. Continuous rolling under light eliminates the need for complex light manipulation. This new movement method offers an insight for various application scenarios.