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A flexible system for closed-loop ventilator development.

W I Marsh·W D Smith
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Abstract

The feasibility of using a microcomputer to regulate the delivery of artificial ventilation was investigated experimentally. To carry out this study, a sampled-data proportional, integral, derivative feedback controller was implemented on a commercial microcomputer and interfaced with a digital/analogue model of a prototype ventilator and two-compartment patient. The microcomputer sampled end-tidal CO2 and calculated a new frequency of ventilation from the difference of end-tidal CO2 and a desired set point value. Use of a microcomputer programmable in BASIC allowed easy manipulation of feedback structure. With the proper choice of feedback constants, the microcomputer was able to maintain end-tidal CO2 at a desired set point.

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Carbon DioxideComputersFeedbackHumansMicrocomputersVentilators, MechanicalJournal Article

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W I Marsh, W D Smith. 1982. A flexible system for closed-loop ventilator development.. https://doi.org/10.1007/bf00994120

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