aalto1 untyped-item.component.html

Eco-friendly disposable sensor node for smart diaper applications

Loading...
Thumbnail Image

URL

Journal Title

Journal ISSN

Volume Title

School of Electrical Engineering | G5 Artikkeliväitöskirja | Defence date: 2025-08-15
Electronic archive copy is available via Aalto Thesis Database.

Date

Major/Subject

Mcode

Degree programme

Language

en

Pages

89 + app. 83

Series

Aalto University publication series Doctoral Theses, 118/2025

Abstract

The aging population poses challenges in monitoring incontinence as elderly individuals are often hesitant to seek assistance due to social stigma, resulting in skin and urinary issues. This is especially critical for bedridden or dementia patients who cannot manage hygiene or communicate diaper wetness, resulting in skin rashes, inflammation, and infections. Smart diaper technology proves potential solutions but faces obstacles related to expensive, bulky electronics, battery maintenance, and environmental issues. This thesis presents a novel implementation of an economical, battery-less, sustainable, disposable, and flexible IoT sensor node for smart diapers that enables real-time wetness monitoring. It is designed to identify multiple urination events and quantify voided volumes using harvested green energy from the application, all without imposing additional burden on caregivers. This work explores the use of printed eco-friendly capacitive sensors on flexible substrates to detect fluid absorption through variations in dielectric permittivity. It also investigates urine-based galvanic cells to harvest energy using printed electrodes on diaper back sheets to power sensor nodes. This battery-less approach addresses challenges like power supply, cost, environmental impact, and caregiver training, enabling continuous operation. This study introduces a novel integration of printed energy-harvesting electrodes and capacitive sensors fulfilling dual functions of energy harvesting and reliable quantification of voided volume while conserving printed materials. The system combines printed elements with ultra-low-power Application Specific Integrated Circuits (ASICs), including a custom capacitance-to-frequency (C2F) converter and frequency-to-digital (F2D) converter, to reliably process and digitize data. A power management unit (PMU) ensures stable operation by regulating the harvested energy. This thesis also explores ASIC frontend using flexible integrated circuit (FlexIC) technology as a sustainable alternative to silicon fabrication, enabling low-cost, flexible on-chip electronics for wearable sensor nodes and expediting development cycles. This advancement promotes biomedical IoT sensors by offering scalable, ecofriendly, and cost-effective healthcare solutions. The system is validated through in-jar and in-diaper experiments, demonstrating urination events detection, voided volume quantification of as low as 30 ml, and differentiation of intermittent episodes. The harvested energy from voided volumes ≥90 ml is capable of powering ASIC for 6 hours, maintaining a stable 1.1 V output. The integration of printed electronics, energy harvesting, and power-efficient ASICs offers an economical, sustainable solution for smart hygiene products, reducing manual diaper checks, improving caregiver efficiency, and enhancing patient comfort. Future work will focus on AI-based data processing and multi-sensor integration to enhance geriatric and incontinence care diagnostic capabilities. Clinical studies are needed to validate results, alongside further research on parameters like electrolyte and glucose concentrations.

Description

Supervising professor

Halonen, Kari, Prof., Aalto University, Department of Electronics and Nanoengineering, Finland

Thesis advisor

Halonen, Kari, Prof., Aalto University, Department of Electronics and Nanoengineering, Finland

Other note

Parts

  • [Publication 1]: Muhammad Tanweer, Raimo Sepponen, Ihsan Oguz Tanzer, and Kari Halonen. Development of Capacitive Sensors to Detect Quantify Fluids in the Adult Diaper. In Proc. International Conference on Bioinspired Information and Communications Technologies, Okinawa, Japan, pp. 237-245, September 2023.
    DOI: 10.1007/978-3-031-43135-7_23 View at publisher
  • [Publication 2]: Muhammad Tanweer, Liam Gillan, Raimo Sepponen, Ihsan Oguz Tanzer, Kari A. Halonen. Evaluation of Printed Coplanar Capacitive Sensors for Reliable Quantification of Fluids in Adult Diaper. In Proc. Mediterranean Conference on Medical and Biological Engineering and Computing & International Conference on Medical and Biological Engineering, Sarajevo, Bosnia-Herzegovina, pp. 414-422, September 2023.
    DOI: 10.1007/978-3-031-49068-2_42 View at publisher
  • [Publication 3]: Muhammad Tanweer, Raimo Sepponen, Ihsan Oguz Tanzer, Kari Halonen. Sustainable Printed Electrodes for Energy Harvesting from Urine to Power IoT Sensor Nodes in Smart Diapers. In Proc. International Joint Conference on Biomedical Engineering Systems and Technologies, Rome, Italy, pp. 65-70, February 2024.
    DOI: 10.5220/0012424100003657 View at publisher
  • [Publication 4]: Muhammad Tanweer, Raimo Sepponen, Ihsan Oguz Tanzer, Kari A. Halonen. Printed Energy Harvesting Electrodes: Sustainable Power Solutions for Batteryless Smart Diapers. Springer Nature Computer Science, Vol. 6, Article no. 391, March 2025.
    DOI: 10.1007/s42979-025-03887-5 View at publisher
  • [Publication 5]: Muhammad Tanweer, Dipesh C. Monga, Liam Gillan, Raimo Sepponen, Ihsan Oguz Tanzer, Kari A. Halonen. Smart Diaper with Printed Capacitive Sensors and Integrated Front-end to Monitor Voided Fluid Volume. IEEE Sensors Journal, Vol. 24, Issue no. 9, pp. 14443-14453, March 2024.
    DOI: 10.1109/JSEN.2024.3380890 View at publisher
  • [Publication 6]: Muhammad Tanweer, Dipesh C. Monga, Gaurav Singh, Liam Gillan, Raimo Sepponen, Ihsan Oguz Tanzer, Kari A. Halonen. Urine-Powered Batteryless Sensor Node with Printed Harvesters and Sensors for Smart Diapers. IEEE Internet of Things Journal, 12 pages, February 2025 (submitted).
    DOI: 10.1109/JIOT.2025.3573459 View at publisher
  • [Publication 7]: Muhammad Tanweer, Dipesh C. Monga, and Kari Halonen. Ultra-Low-Power Frontend Design on Flexible IC Technology for Capacitive Sensors. In Proc. IEEE International Conference on Flexible Printable Sensors and Systems, Tampere, Finland, pp. 1-4, June 2024.
    DOI: 10.1109/FLEPS61194.2024.10603811 View at publisher

Citation

Endorsement

Review

Supplemented By

Referenced By