Self-weighing, self-powered smart diaper

Unmet Need: Hygienic continuous monitoring of urinary output in babies.

Urinary output (UO) is an important metric in the diagnosis, monitoring and treatment of many disorders including kidney disease, heart failure, dehydration, and shock. Premature infants suffer from several factors that make them especially vulnerable to fluid and electrolyte imbalances. The current measurement for UO involves diaper removal, movement to a common area for weighing, zeroing the scale with an unused diaper, and weighing of used diaper. The clinician documents the output, date, and time, and then cleans the common area, including the scale with a disinfecting agent. This repetitive and monotonous task is associated with lapses in judgement and errors, unhygienic conditions and frequent disinfecting with potentially toxic chemicals. Furthermore, the presence and possible spread of bacteria and other pathogens poses a considerable threat to vulnerable babies.

The Technology: Use of electronic sensor based diaper.

Researchers at Washington State University’s College of Nursing, School of Electrical Engineering, and Department of Apparel, Merchandising, Design & Textiles have developed a wearable microelectronic system to sense fluid volume inside a diaper and automatically record it via a base station which powers the tag and a textile-based (piezo-resistive/strain) flexible sensor to accurately estimate volume in a diaper as a function of physical changes e.g. sensor expansion. A radio-frequency identification (RFID)-based custom-silicon tag is attached to the diaper. An omnidirectional antenna with a small footprint is embedded in the textile base. Methods for the base station/scanner to store infant specific-volume measures and output them via both a visual display and an electronic medical record (EMR) interoperable ready digital output.

Applications:

• Monitor urinary output in new born babies, record them against time.

Advantages:

• Highly energy-efficient (power consumption < 500 nW), non-battery dependent, ambient-powered chip enabling longer usage time.

• Low-cost textile-based sensor resulting in accurate volume of fluid in diaper.

• High hygiene maintenance and zero usage of toxin based disinfectant.

Patent Information:

United States Patent PCT/US2017/041797 published on 01/18/2018.