Dual‐responsive and bidirectional bending actuators based on a graphene oxide composite for bionic soft robotics

Abstract

Intelligent actuators have become a research hotspot in smart materials in recent years due to their diverse modes of actuation, various types of deformation, and wide range of applications. However, the application fields of the traditional bilayer actuator that can only be driven by a single stimulus are greatly limited.

Multi-responsive and programmable actuators made with nacre-inspired graphene oxide-bacterial cellulose film

“…Conversely, the GO-BC film absorbs water molecules from the environment resulting in the volume expansion of the GO-BC film, when the ambient humidity increases. 32,37 Thus, the GO-BC film also has the ability of hygroexpansion that is similar to the GO or BC film. However, PET/PEDOT:PSS conductive tape is not sensitive to the changes in ambient humidity, showing insignificant volume change during the change of ambient humidity.…”

“…When the GO-BC/PET/PEDOT:PSS actuator is used as a thermal actuator, the GO-BC film can convert light energy into thermal energy using the photothermal effect, while the PET/ PEDOT:PSS conductive tape can convert electrical energy using the Joule heating effect. After the GO-BC/PET/PEDOT:PSS actuator is heated, the volume of the PET/PEDOT:PSS layer expands due to its large CTE (PET:38 ppm K À1 ), 37 while that of the GO-BC layer does not change significantly due to its inherently low CTE (GO: 0.85 ppm K À1 , BC: 0.1 ppm K À1 ). 32,38 Therefore, during the thermal actuation process of the GO-BC/PET/PEDOT:PSS actuator, the GO-BC layer acts as the inert layer, while the PET/PEDOT:PSS layer acts as the active layer.…”

“…S5, ESI †) and convert it into heat due to the strong ability of light absorption in the wavelength from visible to infrared of GO sheets. 37 The PET/PEDOT:PSS layer of the actuator is also heated by the GO-BC film due to the tightly bound of these two layers. There is a big difference in CTEs between the GO-BC layer and the PET/PEDOT:PSS layer.…”

“…Most GO-based actuators cannot be driven by electrical stimulus due to the insulation of the GO and polymers. 29,32,37,39 Here, the conductive polymer (PEDOT:PSS) is innovatively introduced into the GO-BC/PET/PEDOT:PSS actuator to enable its electrical-driven property. The mechanism of the electricaldriven actuation of the actuator is schematically shown in Fig.…”

Soft pneumatic actuator from particle reinforced silicone rubber: Simulation and experiments

“…Besides, there is another problem that the precise control of the motion of soft actuators could be hindered by the strong nonlinearities of polymer materials and the complex geometries. 14,15 Simulation is necessary in the development of soft actuators since it is helpful in reducing cost, optimizing geometrical parameters in design and predicting bending angle and output force in control. 16,17 At present, the finite element method (FEM) may be the mostly adopted because of the limitations of analytical methods and empirical methods.…”