Authors - Kazunori Minetaki Abstract - This study analyzed care workers' fatigue and stress levels through facial expression analysis, specifically using Percentage of Eye Closure (PERCLOS) and action units. A weighted average of AU04 and AU07 for the action unit analysis was used as an index. The results showed that several participants exhibited relatively high values in both PERCLOS, measuring the percentage of time eyes are closed, indicating drowsiness or fatigue based on eyelid closure duration. and the weighted average of AU04 and AU07, indicating higher fatigue or stress levels. Follow-up interviews with these individuals revealed that they were experiencing significant mental and physical strain due to responsibilities such as overseeing the overall operation of the care facility or dealing with interpersonal issues. Facial expression analysis, being non-invasive and time-efficient, shows potential as a practical tool for monitoring the condition of care workers in real-world settings. The findings are expected to inform interventions that support caregiver well-being and foster healthier work environments.
