A Self-Powered Wireless Temperature Sensor Platform for Foot Ulceration Monitoring

Area of Science:

• Biomedical Engineering
• Wearable Technology
• Sensor Systems

Background:

• Diabetic foot ulceration poses a significant health risk, necessitating continuous monitoring.
• Existing monitoring systems often require external power sources, limiting their practicality.
• Wireless sensor platforms offer potential for remote patient monitoring.

Purpose of the Study:

• To develop a self-powered wireless temperature sensor platform for diabetic foot ulcer monitoring.
• To investigate the energy harvesting capabilities of piezoelectric materials for powering the sensor.
• To evaluate the performance and efficiency of the developed sensor prototype.

Main Methods:

• A sensor platform integrating a piezoelectric bimorph for energy harvesting, a power conditioning circuit, a temperature sensor readout, and a wireless module was designed.
• The energy requirement for data transmission was calculated (4.826 mJ per 18-byte packet).
• Prototype evaluation involved five subjects with varying weights and foot shapes during walking.

Main Results:

• The piezoelectric bimorph effectively converted foot movement into electrical energy to power the sensor.
• Average walking times to transmit data packets were 119.6 s for the first and 71.2 s for subsequent packets.
• The temperature sensor achieved a resolution of 0.1 °C and a sensitivity of 56.7 mV/°C, with 74.5% power conditioning efficiency.

Conclusions:

• The self-powered wireless temperature sensor platform is a viable solution for diabetic foot ulcer monitoring.
• The system demonstrates efficient energy harvesting from natural foot movements.
• This technology can enable continuous, non-invasive monitoring, potentially improving patient outcomes.