Motion Artifact Mitigation for Wearable Pulse Oximetry

A wearable oximeter is needed to help people safely perform missions in environmental extremes. Key initial needs are monitoring for hypoxemia at high altitudes and monitoring for shock from trauma and hemorrhage. The forehead has been confirmed to be an excellent site for signal quality, but signal corruption due to movement, which causes changes in sensor orientation and contact pressure, needs to be mitigated. In this paper a motion artifact mitigation algorithm is described that uses features derived from a pulse plethysmograph (PPG) and co-located accelerometer to identify and discard motion corrupted signals, thereby retaining high accuracy estimates of heart rate (HR) and blood oxygenation (SpO2) while stationary, walking, and running.