The programmable nature of smart textiles makes them an indispensable part of an emerging new technology field. Smart textile‐integrated microelectronic systems (STIMES), which combine microelectronics and technology such as artificial intelligence and augmented or virtual reality, have been intensively explored. A vast range of research activities have been reported. Many promising applications in healthcare, the internet of things (IoT), smart city management, robotics, etc., have been demonstrated around the world. A timely overview and comprehensive review of progress of this field in the last five years are provided. Several main aspects are covered: functional materials, major fabrication processes of smart textile components, functional devices, system architectures and heterogeneous integration, wearable applications in human and nonhuman‐related areas, and the safety and security of STIMES. The major types of textile‐integrated nonconventional functional devices are discussed in detail: sensors, actuators, displays, antennas, energy harvesters and their hybrids, batteries and supercapacitors, circuit boards, and memory devices.

Artificial yarn muscles, behaving like real muscles but providing higher energy output, have attracted considerable interest recently. However, the yarn muscles driven by the low-voltage electrochemical ion injection still suffer...

To address the lack of a suitable electrolyte that supports the stable operation of the electrochemical yarn muscles in air, an ionic‐liquid‐in‐nanofibers sheathed carbon nanotube (CNT) yarn muscle is prepared. The nanofibers serve as a separator to avoid the short‐circuiting of the yarns and a reservoir for ionic liquid. The ionic‐liquid‐in‐nanofiber‐sheathed yarn muscles are strong, providing an isometric stress of 10.8 MPa (about 31 times the skeletal muscles). The yarn muscles are highly robust, which can reversibly contract stably at such conditions as being knotted, wide‐range humidity (30 to 90 RH%) and temperature (25 to 70 °C), and long‐term cycling and storage in air. By utilizing the accumulated isometric stress, the yarn muscles achieve a high contraction rate of 36.3% s−1. The yarn muscles are tightly bundled to lift heavy weights and grasp objects. These unique features can make the strong and robust yarn muscles as a desirable actuation component for robotic devices.

Integrating sense in a thin artificial muscle fiber for environmental adaption and actuation path tracing, as a snail tentacle does, is highly needed but still challenging because of the interfacing mismatch between the fiber’s actuation and sensing components. Here, we report an artificial neuromuscular fiber by wrapping a carbon nanotube (CNT) fiber core in sequence with an elastomer layer, a nanofiber network, and an MXene/CNT thin sheath, achieving the ingenious sense-judge-act intelligent system in an elastic fiber. The CNT/elastomer components provide actuation, and the sheath enables touch/stretch perception and hysteresis-free cyclic actuation tracing due to its strain-dependent resistance. As a whole, the coaxial structure builds a dielectric capacitor that enables sensitive touchless perception. The key to seamless integration is to use a nanofiber interface that allows the sensing layer to adaptively trace but not restrict actuation. This work provides promising solutions for closed-loop control for future intelligent soft robots.

An MXene/SWCNTs-coated CNT@PDMS coaxial muscle fiber with bi-lengthwise actuation driven by solvent to elongate and electrothermally to contract has a linear self-position sensing signal dependent on the contraction of the muscle.

The contraction behavior of spider dragline silk upon water exposure has drawn particular interest in developing humidity-responsive smart materials. We report herein that the spider dragline silk yarns with moderate twists can generate much improved lengthwise contraction of 60% or an isometric stress of 11 MPa when wetted by water. Upon the removal of the absorbed water, the dried and contracted spider silk yarns showed programmable contractile actuations. These yarns can be plastically stretched to any specified lengths between the fully contracted state and the state before supercontraction and return to the fully contracted state when wetted. Moreover, the generated isometric stress of these yarns is also programmable, depending on the stretching ratio. The mechanism of the programmable reversible contraction is based on the plastic mechanical property of the dried and contracted spider silk yarns, which can be explained by the variation of the hydrogen bonds and the secondary structures of the proteins in spider dragline silk. Humidity alarm switches, smart doors, and wound healing devices based on the programmable contractile actuations of the spider silk yarns were demonstrated, which provide application scenarios for the supercontraction of spider dragline silk.

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The rapid development of wearable electronics has accelerated the development of wearable energy storage devices. Wearable supercapacitors have aroused widely interest due to their large power density. However, there are still many challenges in the practical application of wearable supercapacitors. This paper summarizes the structure, working mechanism, materials and key parameters of wearable supercapacitors. And we reviewed the challenges of wearable supercapacitors in practical applications, namely safety, mechanical adaptability, self‐charging capability, environmental tolerance, and multifunction. Finally, these challenges are summarized and prospected. We hope to inspire some work to solve the practical application challenges of wearable supercapacitors.