Fatigue detection using a pressure sensor chair

Fatigue is considered a contributing factor to accidents and illnesses at work. Hence, detecting fatigue by routinely monitoring an individual´s person health is useful in preventing accidents and illnesses. There are many conventional methods for detecting fatigue; However, these methods require users to monitor the extent of their fatigue with gauges and instruments that can restrict users´ actions. On the other hand, fatigue detection using posturography can mitigate this problem. This study focuses on posturography in seated position, because sitting is quite a common action in daily life, and posturography in seated position can be measured without restricting the users´ movement. Posturography in seated position is measured when subjects sit on a chair attached to a pressure sensor sheet. We formed an assumption that the more tired a person is, the more rapidly the COP (center of pressure) converges toward a point. Based on this assumption, we investigated the difference between postural sway in seated position as subjects went from experiencing a condition of fatigue to non-fatigue. Experimental result showed that the COP for left-right axis for subjects experiencing fatigue converged earlier than for those experiencing non-fatigue.