Nowadays, electronic devices are ubiquitous. This spread across all scientific fields
has allowed for greater development of solutions for problems once thought impossible, or
impractical, to solve. Most specifically, it leads to a constant cost reduction in previously
expensive technology, to a point where university students can acquire these devices and
tinker with them, even finding applications that were not initially thought for the device.
As a result, we began the development of this e-nose system, since it became increasingly
important to know and understand the constituents and source of a chemical sample.
This dissertation arises from the need to integrate the computational power inherent
to a low-cost microcontroller unit, to identify chemical substances and their characteristics.
With the main goal set, it was possible to formulate the guidelines to achieve a
successful data acquisition channel for an e-nose system implementation with reduced
costs, size and fast execution. The starting point consisted in understanding how previous
implementations of this system work, as well as its most basic components. After
researching and studying e-nose technologies, I was able to define two separate segments
for a data acquisition channel: acquisition & communication module (hardware) and a
data pre-processing module (software). By using a conductive polymer sensor with a
PSoC 5LP microcontroller unit, it was possible to detect changes in the sensor response
according to the chemical sample being tested, acquire this signal with the Delta Sigma
ADC and, straight away, send this data to the computer where it would be pre-processed.
This stage was implemented in Python and with its extensive signal processing libraries.
Its main goal was to receive and store the data so that it could be use on a future
pattern recognition algorithm to reach the final e-nose conclusion. Since this displayed
to the user, a GUI was developed, and the resulting acquisitions could be displayed in
several plots, as a way of verifying a successful operation.
In the end, it was a success, since after performing acquisition, communication and
displaying the results, subtle differences were visible on the plots displayed
