Tema da Tese: Sobre a Qualidade dos Dados em Sensoriamento de Baixo Custo para Caracterização Ambiental de Espaços Urbanos

Autor: Tiago Costa de Araújo

Programa Doutoral: Programa Doutoral em Engenharia Eletrónica e de Computadores

Orientadores:  Adriano Jorge Moreira; Lígia Torres Silva

Data: 11/03/2020

Abstract: This work investigates the quality of low – and ultra-low – cost sensors that may be applied in environmental monitoring campaigns in urban areas, given its nominal operation features. Sensors of temperature, humidity, atmospheric pressure, carbon monoxide, carbon dioxide and ozone were investigated, chosen from a selection of commercial models available, often used in the instrumentation of initiatives in operation.

The climatic sensors were analysed under the conditions of a climatic controlled chamber where different situations for temperature and humidity were programmed. As results, it was observed that: most of the temperature sensors shown satisfactory performance; the humidity sensors have shown moderate performance; the pressure sensors shown good agreement between them, but it was observed that they suffer some interference from temperature, and it can be crucial to its accuracy when applied outdoors.

The carbon dioxide sensors were evaluated by the comparison of their data with a reference instrument during indoors exposition to indoors concentrations and has shown good results, and some of them are ready for use. The carbon monoxide sensors have not shown conclusive results about its accuracy, but it has promising performance for configuration to lower concentrations. Ozone sensors did not provide conclusive results: either positive neither negative.

In general terms, it can be concluded that climatic sensors can provide useful data if used carefully. Gas sensors, however, are much more critic, considering that its handling is not intuitive, and its readings, without treatment, presented limited quality.

Keywords: Low cost sensors, Data Quality, Environmental Monitoring.