Desenvolvimento de um nariz eletrônico com amostragem a vácuo aplicado a compostos voláteis

Abstract

Electronic noses are devices composed of a gas sensor array, aiming to acquire electrical signals from different concentrations of volatile compounds (VCs) in air, and later process these signals, aiming to identify or classify these compounds. In this manner, this work aims to develop a prototype based on a previous version, aiming to expand the employed sensors, better electromechanical stability, ease-of-use and a perspective of data acquisition through sampling by pressure change. A prototype comprised of 18 sensors with a wide variety of specifications was developed, so that a higher applications range could be verified later, besides that, an interface for wireless setup and data acquisition, with data collection steps automated by a vacuum pump and electromechanical valves. The prototype’s validation was done by benchmarking it’s auxiliary circuitry, including synchronism and operation range tests, followed by sampling ethyl alcohol in varied concentrations. Future projects include the improvement on the sealing materials, as well as the analysis of response as function of pressure and classification of samples.