An All-Printed, Fast-Response Flexible Humidity Sensor Based on Hexagonal-WO3 Nanowires for Multifunctional Applications

The utilization of printing techniques for the development of high-performance humidity sensors holds immense significance for various applications in the fields of the Internet of Things, agriculture, human healthcare, and storage environments. However, the long response time and low sensitivity of current printed humidity sensors limit their practical applications. Herein, a series of high-sensing-performance flexible resistive-type humidity sensors is fabricated by the screen-printing method, and hexagonal tungsten oxide (h-WO3 ) is employed as the humidity-sensing material due to its low cost, strong chemical adsorption ability, and excellent humidity-sensing ability. The as-prepared printed sensors exhibit high sensitivity, good repeatability, outstanding flexibility, low hysteresis, and fast response (1.5 s) in a wide relative humidity (RH) range (11-95% RH). Furthermore, the sensitivity of humidity sensors can be easily adjusted by altering the manufacturing parameters of the sensing layer and interdigital electrode to meet the diverse requirements of specific applications. The printed flexible humidity sensors possess immense potential in various applications, including wearable devices, non-contact measurements, and packaging opening state monitoring.

Fiber-Optic Based Smart Textiles for Real-Time Monitoring of Breathing Rate

Wearable light textiles are gaining widespread interest in application for measurement and monitoring of biophysical parameters. Fiber optic sensors, in particular Bragg Grating (FBG) sensors, can be a competitive method for monitoring of respiratory behavior for chest and abdomen regions since the sensors are able to convert physical movement into wavelength shift. This study aims to show the performance of elastic belts with integrated optical fibers during the breathing activities done by two volunteers. Additionally, the work aims to determine how the positions of the volunteers affect the breathing pattern detected by optical fibers. As a reference, commercial mobile application for sensing vibration is used. The obtained results show that the FBGs are able to detect chest and abdomen movements during breathing and consequently reconstruct the breathing pattern. The accuracy of the results varies for two volunteers but remains consistent.

Cardiorespiratory system monitoring using a developed acoustic sensor

This Letter proposes a wireless acoustic sensor for monitoring heartbeat and respiration rate based on phonocardiogram (PCG). The developed sensor comprises a processor, a transceiver which operates at industrial, scientific and medical band and the frequency of 2.54 GHz as well as two capacitor microphones which one for recording the heartbeat and another one for respiration rate. To evaluate the precision of the presented sensor in estimating heartbeat and respiration rate, the sensor is tested on the different volunteers and the obtained results are compared with a gold standard as a reference. The results reveal that root-mean-square error are determined <2.27 beats/min and 0.92 breaths/min for the heartbeat and respiration rate in turn. While the standard deviation of the error is obtained <1.26 and 0.63 for heartbeat and respiration rate, respectively. Also, the sensor estimate sounds of [Formula: see text] to [Formula: see text] obtained PCG signal with sensitivity and specificity 98.1% and 98.3% in turn that make 3% improvement than previous works. The results prove that the sensor can be appropriate candidate for recognising abnormal condition in the cardiorespiratory system.