An optimal controller with synthetic fuzzy logic for tracking mean arterial pressure

This paper proposes a new noninvasive measurement method for tracking the tendency of mean arterial pressure (MAP) in the radial artery. The designed system consists of a tonometer, a micro syringe device, and a model-based fuzzy logic controller. The modified flexible diaphragm tonometer is to detect the continuous blood pressure waveform and vessel volume pulse. A precise mathematical model describing the interaction between the tonometer and artery is derived. To reach accurate measurement without distortion, an optimal controller is designed to compensate the change of MAP by applying a counter pressure on the tonometer chamber through the micro syringe device. Simulation results show that, for the real physiologic MAP with changing rates up to 20 or -20 mm-Hg/minute, the optimal controller can beat-to-beat adjust the tonometer's chamber pressure to follow the tendency of MAP accurately.