Microwave Humidity Sensor for Early Detection of Sweat and Urine Leakage

A planar microwave sensor devoted to the detection of humidity in underwear and clothes in general is proposed. The ultimate goal of the sensor is to detect the presence of liquids in fabrics, which is of interest to aid patients who suffer from certain pathologies, such as hyperhidrosis and enuresi...

Full description

Bibliographic Details
Main Authors: Lijuan Su, Paris Vélez, Pau Casacuberta, Jonathan Muñoz-Enano, Ferran Martín
Format: Article
Language:English
Published: MDPI AG 2023-05-01
Series:Electronics
Subjects:
Online Access:https://www.mdpi.com/2079-9292/12/10/2276
_version_ 1797600327283769344
author Lijuan Su
Paris Vélez
Pau Casacuberta
Jonathan Muñoz-Enano
Ferran Martín
author_facet Lijuan Su
Paris Vélez
Pau Casacuberta
Jonathan Muñoz-Enano
Ferran Martín
author_sort Lijuan Su
collection DOAJ
description A planar microwave sensor devoted to the detection of humidity in underwear and clothes in general is proposed. The ultimate goal of the sensor is to detect the presence of liquids in fabrics, which is of interest to aid patients who suffer from certain pathologies, such as hyperhidrosis and enuresis. The main target in the design of the sensor, considering the envisaged application, is simplicity. Thus, the sensor operates at a single frequency, and the working principle is the variation in the magnitude of the transmission coefficient of a matched line loaded with an open-ended quarter-wavelength sensing stub resonator. The stub, which must be in contact with the so-called fabric under test (FUT), generates a notch in the transmission coefficient with a resonance frequency that depends on the humidity level of the fabric. By designing the stub with a moderately high-quality factor, the variation in the resonance frequency causes a significant change in the magnitude level at the operating frequency, which is the resonance frequency when the sensing stub is loaded with the dry fabric, and the presence of liquid can be detected by means of an amplitude detector. A prototype device is proposed and experimentally validated. The measured change in the magnitude level by simply depositing one 50 μL drop of water in the FUT is roughly 25 dB.
first_indexed 2024-03-11T03:46:50Z
format Article
id doaj.art-837dbcee596f42a2b52ca9273e5285a3
institution Directory Open Access Journal
issn 2079-9292
language English
last_indexed 2024-03-11T03:46:50Z
publishDate 2023-05-01
publisher MDPI AG
record_format Article
series Electronics
spelling doaj.art-837dbcee596f42a2b52ca9273e5285a32023-11-18T01:10:09ZengMDPI AGElectronics2079-92922023-05-011210227610.3390/electronics12102276Microwave Humidity Sensor for Early Detection of Sweat and Urine LeakageLijuan Su0Paris Vélez1Pau Casacuberta2Jonathan Muñoz-Enano3Ferran Martín4CIMITEC, Departament d’Enginyeria Electrònica, Universitat Autònoma de Barcelona, 08193 Bellaterra, SpainCIMITEC, Departament d’Enginyeria Electrònica, Universitat Autònoma de Barcelona, 08193 Bellaterra, SpainCIMITEC, Departament d’Enginyeria Electrònica, Universitat Autònoma de Barcelona, 08193 Bellaterra, SpainCIMITEC, Departament d’Enginyeria Electrònica, Universitat Autònoma de Barcelona, 08193 Bellaterra, SpainCIMITEC, Departament d’Enginyeria Electrònica, Universitat Autònoma de Barcelona, 08193 Bellaterra, SpainA planar microwave sensor devoted to the detection of humidity in underwear and clothes in general is proposed. The ultimate goal of the sensor is to detect the presence of liquids in fabrics, which is of interest to aid patients who suffer from certain pathologies, such as hyperhidrosis and enuresis. The main target in the design of the sensor, considering the envisaged application, is simplicity. Thus, the sensor operates at a single frequency, and the working principle is the variation in the magnitude of the transmission coefficient of a matched line loaded with an open-ended quarter-wavelength sensing stub resonator. The stub, which must be in contact with the so-called fabric under test (FUT), generates a notch in the transmission coefficient with a resonance frequency that depends on the humidity level of the fabric. By designing the stub with a moderately high-quality factor, the variation in the resonance frequency causes a significant change in the magnitude level at the operating frequency, which is the resonance frequency when the sensing stub is loaded with the dry fabric, and the presence of liquid can be detected by means of an amplitude detector. A prototype device is proposed and experimentally validated. The measured change in the magnitude level by simply depositing one 50 μL drop of water in the FUT is roughly 25 dB.https://www.mdpi.com/2079-9292/12/10/2276planar microwave sensorhumidity sensormicrostrip technologydetection of sweatdetection of urine leakageenuresis
spellingShingle Lijuan Su
Paris Vélez
Pau Casacuberta
Jonathan Muñoz-Enano
Ferran Martín
Microwave Humidity Sensor for Early Detection of Sweat and Urine Leakage
Electronics
planar microwave sensor
humidity sensor
microstrip technology
detection of sweat
detection of urine leakage
enuresis
title Microwave Humidity Sensor for Early Detection of Sweat and Urine Leakage
title_full Microwave Humidity Sensor for Early Detection of Sweat and Urine Leakage
title_fullStr Microwave Humidity Sensor for Early Detection of Sweat and Urine Leakage
title_full_unstemmed Microwave Humidity Sensor for Early Detection of Sweat and Urine Leakage
title_short Microwave Humidity Sensor for Early Detection of Sweat and Urine Leakage
title_sort microwave humidity sensor for early detection of sweat and urine leakage
topic planar microwave sensor
humidity sensor
microstrip technology
detection of sweat
detection of urine leakage
enuresis
url https://www.mdpi.com/2079-9292/12/10/2276
work_keys_str_mv AT lijuansu microwavehumiditysensorforearlydetectionofsweatandurineleakage
AT parisvelez microwavehumiditysensorforearlydetectionofsweatandurineleakage
AT paucasacuberta microwavehumiditysensorforearlydetectionofsweatandurineleakage
AT jonathanmunozenano microwavehumiditysensorforearlydetectionofsweatandurineleakage
AT ferranmartin microwavehumiditysensorforearlydetectionofsweatandurineleakage