This paper proposes a monitoring system for a human respiration and posture in sleep using pressure sensor array. The proposed system consists of 221 pressure sensors (Force Sensing Resistors: FSRs) attached to the surface of the bed. Each sensor of the pressure sensor array is set 5 [cm] apart. The novel features of the proposed system lie in non-invasive and unrestrained monitoring of the human respiration and posture. Non-invasive monitoring eliminates the need for monitoring needles or catheters to invade the human body, sensors thus do not impose a physiological burden such as pain on him or her. In unrestrained monitoring, sensors and their electrical cords do not limit degrees of freedom of his or her movement. Unrestrained sensing therefore does not impose a psychological burden caused by the limitations on him or her. Experimental results demonstrate that the proposed system is feasible for monitoring a human respiration and posture for over 6 hours.
