Water-Modulated Biomimetic Hyper-Attribute-Gel Electronic Skin for Robotics and Skin-Attachable Wearables

Abstract

Electronic skin (e-skin), mimicking the physical–chemical and sensory properties of human skin, is promising to be applied as robotic skins and skin-attachable wearables with multisensory functionalities. To date, most e-skins are dedicated to sensory function development to mimic human skins in one or several aspects, yet advanced e-skin covering all the hyper-attributes (including both the sensory and physical–chemical properties) of human skins is seldom reported. Herein, a water-modulated biomimetic hyper-attribute-gel (Hygel) e-skin with reversible gel–solid transition is proposed, which exhibits all the desired skin-like physical–chemical properties (stretchability, self-healing, biocompatibility, biodegradability, weak acidity, antibacterial activities, flame retardance, and temperature adaptivity), sensory properties (pressure, temperature, humidity, strain, and contact), function reconfigurability, and evolvability. Then the Hygel e-skin is applied as an on-robot e-skin and skin-attached wearable to demonstrate its highly skin-like attributes in capturing multiple sensory information, reconfiguring desired functions, and excellent skin compatibility for real-time gesture recognition via deep learning. This Hygel e-skin may find more applications in advanced robotics and even skin-replaceable artificial skin.

A Pathway into Metaverse: Gesture Recognition Enabled by Wearable Resistive Sensors

“…[31] Duan et al proposed a water-modulated biomimetic hyper-attribute-gel (Hygel) e-skin composed of MXene and silk fibroin (Figure 4b). [57] This hyper-attribute Hygel exhibited high resolution in strain sensing for bending angles, which is eligible for hand motion monitoring and dynamic gesture recognition with long-term wearing comfort, biocompatibility, and safety. This Hygel e-skin was used to achieve 1D-CNN (one-dimensional convolutional neural network) assisted highprecise classification of 15 dynamic gestures.…”

“…[69][70][71] Yet, more research should be devoted to effectively extending the service life of the hydrogel-based strain sensor, such as improving the mechanical properties of the hydrogel and overcoming the disadvantage of losing water. [57,72] Ionic-liquid-based resistive strain sensors where the sensing layer is often composed of ionic liquid and polymer. For example, Li et al proposed an ultra-durable ionic resistive strain sensor with excellent healing ability by impregnating ionic liquids into the robust poly(urea-urethane) (PU) network (Figure 4f), which was attached to a finger to detect the finger-bending.…”

“…Reproduced with permission. [ 57 ] Copyright 2023, American Chemical Society. c) Liquid‐metal‐based resistive strain sensors.…”

“…b) Conductive-network-based resistive strain sensors. Reproduced with permission [57]. Copyright 2023, American Chemical Society.…”

2D PtSe2 Enabled Wireless Wearable Gas Monitoring Circuits with Distinctive Strain-Enhanced Performance

“…Gas sensing plays an essential role in environmental monitoring, agricultural production, and medical diagnosis, protecting humans from hazardous gases. With the development of next-generation wearable technologies, flexible electronics are designed in multiple forms to meet the various monitoring scenarios. − Sensors are usually attached to the skin surface or embedded in body-worn accessories accompanied by unstable interface states and strain fields, which are critical to the reception, processing and transmission of sensing signals. , Therefore, ensuring real-time, superior sensitive, and highly reliable gas detection has emerged as a current hotspot in the research of the human–machine interface. − …”