Wearable and Flexible Humidity Sensor Integrated to Disposable Diapers for Wetness Monitoring and Urinary Incontinence

Abstract

Disposable diapers are widely used by individuals with urinary incontinence. Diapers should be checked frequently for elderly, disabled, and hospital patients. Wet diapers that are not changed properly can cause health problems. The importance of electronic devices that provide warning in case of wetness is increasing in health monitoring. A disposable and wearable printed humidity sensor was designed and fabricated to detect wetness. The sensor was printed on polyamide-based taffeta label fabric by the inkjet printing method using specifically formulated PEDOT:PSS-based conductive polymer ink. The sensor sensitivity was tested under different relative humidity levels inside a controlled chamber. The resistance of the sensor decreased from 17.05 ± 0.05 MΩ to 2.09 ± 0.06 MΩ as the relative humidity increased from 35 to 100%, while the moisture value of the fabric increased from 4.8 to 23%. The response and recovery times were 42 s and 82 s. This sensor was integrated into the adult diaper to evaluate wetness. The sensor resistance change comparing to the dry state resistance (15.52 MΩ) was determined as 3.81 MΩ to 13.62 MΩ by dripping 0.1 mL to 100 mL salty water on the diaper. Due to its flexible structure and low-cost printability onto fabric, the wearable printed humidity sensor has the potential to be used as a disposable sensor for healthcare applications, particularly for urinary incontinence and capturing wetness in diapers.

Flexible humidity sensor for smart agricultural applications

“…Since the fabricated humidity sensors are resistive type, the electrical properties of the sensors were determined by measuring the resistance changes. To measure the humidity sensor electrical resistance measurements, the measurement stand with humidifier, humidity, and temperature control unit, multimeter, and sensor samples were arranged in a closed chamber as seen in our previous study [18]. Resistance measurements were carried out with the Keithley 2700 Multimeter according to fourpoint probe measurement method.…”

“…The proposed sensor is based on the resistive sensing principle. While the increase in the RH in the environment causes the resistance of the resistive sensors to decrease, it is expected that the resistive humidity sensors give a linear response to the RH changes [18,19]. Compared with other sensing mechanisms, resistive sensors have many advantages.…”

Nano-Materials-Based Printed Glucose Sensor for Use in Incontinence Products for Health-Care Applications

“…The so-called smart incontinence products have been developed [6,7,34,35]. Such systems can only provide for the detection of urine in absorbents.…”

Research on Dynamic Urine Volume Detection System Based on Smart Flexible Textile Sensors

“…In this revolutionary era, smart diapers, as powerful aids for both urinary incontinence patients and caregivers, are bringing convenience and comfort to daily life through their unique smart technology and user-friendly design [12] . Meltem Tekcin et al [13] used an office-type inkjet printer to print conductive PEDOT:PSS polymer ink on polyamide taffeta fabric labels to create humidity sensors. They dripped 0.1 mL to 100 mL of saline solution, simulating urinary incontinence detection on adult diapers.…”