shows the proto-type of the KRISS BP simulator. The simulator consisted of a stepping motor, a lever assembly, a bellows and a pressure transducer. To set the initial position, a photo interrupter was used. The pressure is generated from a BP device under test and the adequate pressure oscillation was generated by the lever assembly from the rotational motion of the stepping motor. At this time, the KRISS simulator generates artificial biosignals that is very similar to human subjects. The pressure oscillations are fed directly into the pneumatic system of the blood pressure monitor being tested via a T piece connector.