Smart radio-frequency identification tag for diaper moisture detection

Area of Science:

• Biomedical Engineering
• Materials Science
• Electrical Engineering

Background:

• Diaper wetness monitoring is crucial for infant health and comfort.
• Current methods may lack non-contact detection or require complex systems.
• A need exists for simple, passive, and reliable dampness detection technology.

Purpose of the Study:

• To develop and demonstrate a passive smart tag for detecting diaper dampness.
• To utilize high-frequency (HF) technology for effective signal penetration.
• To create a non-contact sensor activated by a pre-defined moisture threshold.

Main Methods:

• Design of a passive smart tag incorporating a circular spiral coil and a swelling substrate.
• Utilizing a high-frequency (HF) system operating at 13.56 MHz for detection.
• Simulation and experimental measurement of the prototype tag's performance.
• Integration and demonstration of the tag in a worn diaper.

Main Results:

• The smart tag successfully responds to dampness upon reaching a pre-defined threshold.
• High-frequency operation (13.56 MHz) proved effective for signal transmission through materials.
• The non-contact detection mechanism, facilitated by the coil and swelling substrate, was validated.
• Prototype performance was confirmed through simulations and real-world measurements.

Conclusions:

• A passive smart tag capable of detecting diaper dampness without wearer contact has been successfully developed.
• The HF system and material design enable reliable, non-invasive moisture detection.
• This technology offers a promising solution for improved infant care and monitoring.