A haptic-feedback glove with triboelectric sensors and piezoelectric stimulators is developed for interaction in virtual space.

With the prospect of a smart society in the foreseeable future, humans are experiencing an increased link to electronics in the digital world, which can benefit our life and productivity drastically. In recent decades, advances in the Human Machine Interface (HMI) have improved from tactile sensors, such as touchpads and joysticks, to now include the accurate detection of dexterous body movements in more diversified and sophisticated devices. Advancements in highly adaptive machine learning techniques, neural interfaces, and neuromorphic sensing have generated the potential for an economic and feasible solution for next-generation applications such as wearable HMIs with intimate and multi-directional sensing capabilities. This review offers a general knowledge of HMI technologies beginning with tactile sensors and their piezoresistive, capacitive, piezoelectric, and triboelectric sensing mechanisms. A further discussion is given on how machine learning, neural interfaces, and neuromorphic electronics can be used to enhance next-generation HMIs in an upcoming 5 G infrastructure and advancements in the internet of things and artificial intelligence of things in the near future. The efficient interactions with kinetic and physiological signals from human body through the fusion of tactile sensor and neural electronics will bring a revolution to both the advanced manipulation and medical rehabilitation.

Recent advances in flexible electronics have offered a good opportunity in designing a variety of wearable devices for healthcare monitoring, prevention medicine, and robotic control. Wearable sensors are entering the era of digital health, with compelling functionalities in recording vital signs, physiological signals, body kinetics, and dynamic biomolecular state. Meanwhile, energy harvesters that scavenge waste energy from body motions and the ambient environment have received intense attention, which are expected to realize self-powered or energy-autonomous systems. Moving towards the inside of the body, the implantable device also plays an indispensable role in monitoring key biomedical and physiological information and effective treatment of chronic diseases. Besides, wearable robotic exoskeletons have enabled advanced functionalities of assisting or augmenting human mobilities unprecedently. These technologies and platforms will be merged, giving way to the bodyNET: a network of wearable sensors, implantable devices, and exoskeletons for improved healthcare and health outcomes. In this article, we offer a brief review of recent advances in flexible and wearable sensors and summarize the progress of self-powered wearable sensors based on piezoelectric and triboelectric nanogenerators. We also discuss the implantable devices and self-powered neuromodulation systems and offer recent works of lower-limb exoskeletons. Lastly, we present a future trend towards a comprehensive and capable bodyNET for advanced healthcare and reinforced life quality.

Real-time in situ monitoring of plant physiology is essential for establishing a phenotyping platform for precision agriculture. A key enabler for this monitoring is a device that can be noninvasively attached to plants and transduce their physiological status into digital data. Here, we report an all-organic transparent plant e-skin by micropatterning poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) on polydimethylsiloxane (PDMS) substrate. This plant e-skin is optically and mechanically invisible to plants with no observable adverse effects to plant health. We demonstrate the capabilities of our plant e-skins as strain and temperature sensors, with the application to Brassica rapa leaves for collecting corresponding parameters under normal and abiotic stress conditions. Strains imposed on the leaf surface during growth as well as diurnal fluctuation of surface temperature were captured. We further present a digital-twin interface to visualize real-time plant surface environment, providing an intuitive and vivid platform for plant phenotyping.

Real-time monitoring of plant immune responses is crucial for understanding plant immunity and mitigating economic losses from pathogen and pest attacks. However, current methods relying on molecular-level assessment are destructive and time-consuming. Here, we report an ultrathin, substrate-free, and highly conductive electronic tattoo (e-tattoo) designed for plants, enabling immune response monitoring through non-invasive electrical impedance spectroscopy (EIS). The e-tattoo’s biocompatibility, high conductivity, and sub-100 nm thickness allow it to conform to leaf tissue morphology and provide robust impedance data. We demonstrate continuous EIS analysis of live transgenic Arabidopsis thaliana plants for over 24 h, capturing the onset of NLR-mediated acute immune responses within three hours post-induction, prior to visible symptoms. RNA-seq and tissue ion leakage tests validate that EIS data accurately represent the physiological and molecular changes associated with immune activation. This non-invasive tissue-assessment technology has the potential to enhance our comprehension of immune activation mechanisms in plants and paves the way for real-time monitoring for plant health management.