Design and validation of a forehead pulse oximeter for military medical evacuation
DOI:
https://doi.org/10.24425/mms.2025.154676Abstract
This article presents the design, implementation, and validation of an SpO2 sensor prototype, developed as part of a military medical evacuation system. The reflectance method was chosen for the measurement of SpO2, allowing readings to be taken from any location on the body, unlike the traditional transmissive method. The sensor is designed as a headband worn on the forehead, a well-perfused area, ensuring that the placement does not hinder the mobility of the soldier. The sensor construction utilized an SFH7072 optical module, an AFE4410 integrated circuit, and an STM32L5 microcontroller. To obtain accurate SpO2 readings, signal processing techniques, including filtering, were applied, along with the development of algorithms to calculate SpO2 from photoplethysmographic (PPG) signals. The prototype underwent validation tests using a comprehensive experimental setup. The prototype achieved an ARMS (root mean square difference) value of 3.0%, meeting the ISO 80601-2-61 standard for reflectance sensors, which recommends an 𝐴RMS ≤ 3.5%.References
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