Control System for DC Motor Based Micro Air Pump to Simulate Oscillograph of Blood Pressure

The accuracy and repeatability of the NIBP monitor are still in controversy between clinicians. Automatic NIBP monitor uses oscillometric method to determine systolic blood pressure (SBP) and diastolic blood pressure (DBP). In order to ensure the NIBP monitor works properly, a Noninvasive Blood Pressure Simulator is required to evaluate the NIBP monitor. The objective of this research was to develop a control system of a device which could simulate the similar oscillation produced by the blood pressure. There are two stages to develop the control system, they are reference data taking and prototype evaluation. There are three reference data types taken, first is static pressure, then the dynamic pressure and the last is motor characterization. The pressure sensor was calibrated by obtaining the static pressure data. The dynamic pressure data was used to determine the oscillograph characteristics of each blood pressure presets. The prototype was evaluated by testing the simulator to two calibrated NIBP monitors from two different manufacturers. An NIBP monitor works properly if it has stable and accurate output and high repeatability. This simulator was already able to simulate the repeatability of the NIBP monitor. The maximum error of the simulator was 6.67% at 60/30 mmHg and the largest deviation was ±3 mmHg.