Accurate monitoring of motion and sleep states is critical for human health assessment, especially for a healthy life, early diagnosis of diseases, and medical care. In this work, a smart wearable sensor (SWS) based on a dual-channel triboelectric nanogenerator was presented for a real-time health monitoring system. The SWS can be worn on wrists, ankles, shoes, or other parts of the body and cloth, converting mechanical triggers into electrical output. By analyzing these signals, the SWS can precisely and constantly monitor and distinguish various motion states, including stepping, walking, running, and jumping. Based on the SWS, a fall-down alarm system and a sleep quality assessment system were constructed to provide personal healthcare monitoring and alert family members or doctors via communication devices. It is important for the healthy growth of the young and special patient groups, as well as for the health monitoring and medical care of the elderly and recovered patients. This work aimed to broaden the paths for remote biological movement status analysis and provide diversified perspectives for true-time and long-term health monitoring, simultaneously.

As a new energy harvesting invention [4] with great potential application value, [5] triboelectric nanogenerator (TENG) has gradually advanced, [6] whether in theoretical research, structural innovation, or application development, since its discovery in 2012, [7] which has four main applications nowadays: micronanoenergy, [8] self-powered sensor, [9] blue energy, [10] and high-voltage application. [11] Different from the low-voltage characteristic of the electromagnetic generator, TENG can be considered as a current source [12] with high voltage and low current output characteristics. Therefore, the research on the high-voltage application scenarios and mechanism of TENGs is gradually receiving extensive attention from researchers. [13] Lin et al. designed a TENG with a radially distributed disk structure for the first time, which opens up many novel structures and potential applications. [14] Then, a freestanding rotary triboelectric nanogenerator (FR-TENG) with radial arrays of microsized sectors was designed, which achieved multiple charge transfer and generated higher short-circuit current (I SC ). [15] FR-TENG has received widespread attention due to its characteristics of higher open-circuit voltage (V OC ) and shortcircuit current. [16] However, since the conventional FR-TENGThe soft-contact freestanding rotary triboelectric nanogenerator (FR-TENG), with the capabilities of high output performance and excellent efficiency, presents interesting applications in driven nonequilibrium plasma jets, mass spectrometry, electrospinning, and so on. For enhancing the output performance of FR-TENG, detailed and in-depth research focusing on the design method is discussed in this paper, mainly consisting of the following four parts: 1) design reasonable geometric structure, 2) select triboelectric layers, 3) choose a reasonable signal acquisition, and 4) investigate influencing factors. Benefiting from this four-step systematic research, a modified FR-TENG with better output performance is successfully constructed. A corresponding open-circuit voltage density of 1.27 × 10 5 V m −2 is achieved, which is over twofold higher compared to the largest one among the previous similar articles. Therefore, the four-step systematic research is demonstrated to remarkably enhance the output performance of the soft-contact FR-TENG. This work not only presents a modified FR-TENG with ultrahigh voltage density that inhibits bacterial corrosion, enables high-voltage electrostatic dust removal, and enables impressive current cathodic protection of marine pipelines and urban buried pipelines, but also can be regarded as guidance for the design of soft-contact FR-TENG.

No abstract

No abstract

Triboelectric nanogenerators (TENGs) are attractive in powering sensors for smart power grids. Herein, a TENG based on a rotational magnetic ball is presented to harvest the magnetic energy of transmission lines. The magnetic ball rolls in a spherical shell under the alternating magnetic field generated by the transmission line. The centrifugal force produced during the rotation is used to drive a TENG unit (ten times the weight of the magnetic ball and shell) to generate electricity with the assistance of coil springs. The device can maintain the stability of the output performance under high current shocks; meanwhile, the open‐circuit voltage, output power, and operating frequency of a single TENG unit can reach 1.5 kV, 6.67 mW, and 20 Hz, respectively. Furthermore, a wireless alarm system for monitoring the temperature and dip angle of transmission lines is successfully driven by this device. This work demonstrates an efficient and nontraditional strategy for harvesting magnetic energy through TENG, which is applied to power‐distributed and self‐powered sensors for monitoring transmission lines.

No abstract

No abstract

No abstract