Abstract: A drowsiness detection system is disclosed. The way of detection is by an EEG detection circuit to detect brain waves of a human brain for getting an EEG signal. The EEG signal is sent to a micro-controller circuit to generate a control signal. In accordance with the control signal, a processing circuit processes the EEG signal so as to learn the drowsiness state of the user in time.

Abstract: A contact sensor is disclosed. The contact sensor includes a main body and at least one conductor. At least one end of the conductor is disposed on the main body and a contact surface is on one side of the conductor for contact the body surface. The surface of the conductor is in the shape of arc. By the contact surface of the conductor, the contact sensor contacts the human body easily without tangling hair. Moreover, there is not need for the present invention to apply any conductive gel on the body surface so that the measurement of physiological signals is easily and conveniently.