This paper presents a novel tube flow sensor to measure airflow in mouths for detecting respiration and heartbeat signals of premature babies in incubators. A flow rate sensor with temperature compensation and a flow direction sensor were combined to decrease their footprint on a sensor film. The fabricated sensor film was assembled onto the inside surface of the tube, and its detection properties were investigated. The sensor output in the flow rate sensor obeyed King’s model. The value of output in the flow-direction sensor was changed in accordance with the change of the airflow direction.
