Pencil-Drawn Generator Built-in Actuator for Integrated Self-Powered/Visual Dual-Mode Sensing Functions and Rewritable Display

Untethered Soft Robots Based on 1D and 2D Nanomaterials

Biological structures exhibit autonomous and intelligent behaviors, such as movement, perception, and responses to environmental changes, through dynamic interactions with their surroundings. Inspired by natural organisms, future soft robots are also advancing toward autonomy, sustainability, and interactivity. This review summarizes the latest achievements in untethered soft robots based on 1D and 2D nanomaterials. First, the performance of soft actuators designed with different structures is compared. Then, the development of basic locomotion forms, including crawling, jumping, swimming, rolling, gripping, and multimodal, mimicking biological motion mechanisms under dynamic stimuli, is discussed. Subsequently, various self-sustained movements based on imbalance mechanisms under static stimuli are introduced, including light tracking, self-oscillating, self-crawling, self-rolling, and flying. Following that, the progress in soft actuators integrated with additional functionalities such as sensing, energy harvesting, and storage is summarized. Finally, the challenges faced in this field and the prospects for future development are discussed.

Amphibious Soft Robots Based on Programmable Actuators Fabricated by Brushing Chinese Ink on Paper

Soft robots based on actuators that can work in both on-ground and on-water situations are environmentally adaptable and can accomplish tasks in complex environments. However, most current amphibious actuators need external stimuli to move on water and require complex preparation processes. Herein, amphibious Ink-paper/polyethylene programmable actuators and robots are proposed, which are fabricated by rapidly brushing Chinese ink on paper. The actuator can bend on the ground and move autonomously on the water. On one hand, the actuator shows a maximum bending curvature of 2.66 cm-1 under near-infrared light, and the actuation performance can be programmed by ink concentration. Moreover, actuators with pen-brushed information can be shape-programmed for dynamic information display. On the other hand, the actuator can autonomously move on the water by using Chinese ink as Marangoni fuel. The maximum moving velocity is 4.73 cm s-1. When the ink is saturated in the water, the actuator can further be driven by an infrared laser. Finally, three soft robots with diverse programmable amphibious motions are designed. Both the crawling/bending motion on the ground and autonomous linear/rotary movement on the water can be programmed by altering actuator structures. This research will provide new inspirations for next-generation amphibious actuators and soft robots.

Multi-Functional Actuators Made with Biomass-Based Graphene-Polymer Films for Intelligent Gesture Recognition and Multi-Mode Self-Powered Sensing

Multi-functional actuation systems involve the mechanical integration of multiple actuation and sensor devices with external energy sources. The intricate combination makes it difficult to meet the requirements of lightweight. Hence, polypyrrole@graphene-bacterial cellulose (PPy@G-BC) films are proposed to construct multi-responsive and bilayer actuators integrated with multi-mode self-powered sensing function. The PPy@G-BC film not only exhibits good photo-thermoelectric (PTE) properties but also possesses good hydrophilicity and high Young's modulus. Thus, the PPy@G-BC films are used as active layers in multi-responsive bilayer actuators integrated with self-powered sensing functions. Here, two types of multi-functional actuators integrated with self-powered sensing functions is designed. One is a light-driven actuator that realizes the self-powered temperature sensing function through the PTE effect. Assisted by a machine learning algorithm, the self-powered bionic hand can realize intelligent gesture recognition with an accuracy rate of 96.8%. The other is humidity-driven actuators integrated a zinc-air battery, which can realize self-powered humidity sensing. Based on the above advantages, these two multi-functional actuators are ingeniously integrated into a single device, which can simultaneously perform self-powered temperature/humidity sensing while grasping objects. The highly integrated design enables the efficient utilization of environmental energy sources and complementary synergistic monitoring of multiple physical properties without increasing system complexity.