Photothermal and Humidity Stimulus-Responsive Self-Sensing Soft Actuators for Smart Packaging

Abstract

Soft actuators with both actuation and self-sensing characteristics can better adapt to the environment and more effectively realize intelligent human−machine interactions, which is highly desired for the upcoming era of soft robotics. Herein, a multi-stimulus response actuator (MSRA) is constructed based on the asymmetric expansion principle, and the sensing function is simply and quickly integrated into the soft actuator by screen printing technology. Taking advantage of the good photothermal conversion performance of the dopamine-modified graphene oxide (DGO) layer and the difference in the expansion coefficient between the DGO layer and the poly(vinylidene fluoride)/polydimethylsiloxane layer, the soft actuators exhibit different actuation behaviors under photothermal and humidity stimuli, respectively. Meanwhile, the introduction of a printed carbon black/highly elastic transparent adhesive cement sensing layer gives MSRA a self-sensing function which can provide feedback on its actuation process in real time. In addition, various complex deformations can be achieved by the macroscopic assembly of several actuators. Finally, we show that this soft actuator can be used as a smart packaging material to realize smart packaging. We believe that actuators with sensing feedback are significant in soft robots and smart packaging.

Asymmetric Metal–Organic Framework-Based Mixed Matrix Membrane for Reversible Self-Assembling 3D Architecture

“…Adaptive self-transforming systems are ubiquitous in nature, for example, the folding of mimosa leaflets, the turning of sunflowers, and the bending or twisting of plant seed organs (including pea pods and pinecones), all of the above can take place under the stimulus of the external environment. − The shape-transforming phenomenon has sparked tremendous enthusiasm for the development of programmable and responsive materials that can constantly interact with changes in the external environment. This kind of material can self-assemble from 2D membranes into 3D architectures induced by external stimuli, showing great potential in soft robots, sensors, energy harvesting, flexible electronics, and so on. − …”

Soft Fiber/Textile Actuators: From Design Strategies to Diverse Applications

“…Notably, biological muscles and mimosa leaves showcase mechanical responsiveness to external cues as a means of self-protection. , Inspired by these natural phenomena, researchers have recently devoted efforts toward developing stimuli-responsive soft actuators. − In contrast to conventional rigid actuators, soft actuators possess an excellent ability to acclimate to intricate and dynamic environments, thanks to their outstanding compliance. This characteristic renders them exceptionally well-suited for executing complex tasks. , Among the various soft actuators, those based on fiber materials have garnered significant attention. This interest stems from their heightened degrees of freedom, expansive specific surface area, diverse mechanical properties, ease of configuration, and the capability to form 2D or 3D heterogeneous structures.…”