The master's thesis presents the manufacture and testing of a measuring system for measuring the conductivity of the skin in the form of a computer mouse. The task aimed to create a simple and high-quality measuring system that allows unobtrusive measurement (hidden electrodes). Unobtrusive measurement is desirable because it reduces the impact of measurement anxiety. This is the state of mental tension of the measured person due to participation in the measurement process. Namely, it raises blood pressure and heart rate and increases sweating, which affects the conductivity of the skin.
The aim was also to create software that allows insight into the current values of conductivity during the measurement and graphical representation, which allows the experimenter to decide on the further course of the experiment according to current values, for example, to cause more stress in the case of a small response or to reduce it in the case of an excessive response. Even in the case of a simple experiment, where the intervention of the performer in the course of the experiment is not necessary, the current values can serve as an indicator of whether the measurement is OK or not.
In the practical part of the thesis, some measurement methods for measuring conductivity of the skin and comparison between them are presented, and then skin temperature measurement is described. This is followed by the construction of the measuring system, from the selection of the mouse to the placement of the electrodes, the selection and description of the components of the measuring circuit, and the production of the printed circuit and programming of the microcontroller. The next subsection describes the operation of a dedicated software interface for capturing measurement signals.
Finally, a static and dynamic calibration is performed, and in the end, an experiment that shows the operation of the measuring system in practice.
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