Multistimulus Responsive Actuator with GO and Carbon Nanotube/PDMS Bilayer Structure for Flexible and Smart Devices

TLDR

Smart devices that perceive, process, and respond are increasingly important for artificial intelligence, especially in biomimetic and intelligent robotics. The authors aim to create a highly flexible, multistimulus‑responsive actuator that can mimic creature movements such as weight lifting and object carrying. They fabricate a soft actuator by layering CNT/PDMS with strong photothermal properties over a hydrophilic GO layer, then tune its actuation by directionally aligning GO onto the CNT/PDMS, enabling reversible deformations under light, heat, and humidity. The asymmetric bilayer structure causes the actuator to bend in opposite directions under photothermal versus humidity stimuli, allowing bidirectional controllable bending, and it can be assembled into biomimetic fingers, smart tweezers, and humidity switches for flexible robots, artificial muscles, and optical medical devices.

Abstract

Smart devices with abilities of perceiving, processing, and responding are attracting more and more attentions due to the emerging development of artificial intelligent systems, especially in biomimetic and intelligent robotics fields. Designing a smart actuator with high flexibility and multistimulation responsive behaviors to simulate the movement of creatures, such as weight lifting, heavy objects carrying via simple materials, and structural design is highly demanded for the development of intelligent systems. Herein, a soft actuator that can produce reversible deformations under the control of light, thermal, and humidity is fabricated by combining high photothermal properties of CNT/PDMS layer with the natural hydrophilic GO layer. Due to the asymmetric double-layer structure, the novel bilayer membrane-based actuator showed different bending directions under photothermal and humidity stimulations, resulting in bidirectional controllable bending behaviors. In addition, the actuation behaviors can be well controlled by directionally aligning the graphene oxide onto carbon nanotube/PDMS layer. The actuator can be fabricated into a series of complex biomimetic devices, such as, simulated biomimetic fingers, smart "tweezers", humidity control switches, which has great potential applications in flexible robots, artificial muscles, and optical control medical devices.