Study On Measurement System Of Respiratory Mechanics Parameters

Respiratory Mechanics is a subject which researchs the mechanics problems of respiratory system in respiration physiology by engineering viewpoint and method. The aim of studying mechanics problems of respiratory system, is that it can help to understand respiratory physiology and pathologic, so the research highlight is the measurement of respiratory mechanics parameters. The measuring of respiratory mechanics parameters is an important method of evaluating lung's fuction duaring the patent's operation, and a method of monitoring the current state of ventilator. These are important and significant practically in clinic.The thesis was based on the requirement which was made of real-time measurement of flow and pressure and then derivated the correlact papamenters. The thesis designed a new-style measurement system of respiratory mechanics. The two sides of flow sensor respectively connected the patent's airway and ventilator. Physically the flow sensor was a thin membrane within a housing. The membrane allowed bidirectional flow through its variable orifice. The orifice changed its diameter depending on the folw rate. It opened progressively as the flow increases, creating a pressure drop across the orifice. The pressure difference was then measured by a high-precison differential pressure sensor. The pressure sensors converted two pressure signals into voltage signals of mV Degree. The two voltage signals were amplified by appearance amplifier and then converted the digital signals by A/D converter. MCU system calculated and processed the digital signals, got the folw and airway pressure. Flow, airway pressure and time was the three fundermental parameters which could detrude correlate respiratory mechanics papameters, time was desided by sampling introduce. MCU system transmited flow, pressure and...