In the master's thesis I report on the results of a user study in which I compared the performance of two commercially available devices for measuring drivers' physiological signals. These are Empatica E4 and Bittium's Faros 360 devices, which allow the measurement of heart rate variability (HRV), but each in its own way. Empatica uses the method of photoplethysmography (PPG), Faros measures the ECG signal. The goal was to determine if these two devices can successfully detect the drivers' responses to different traffic situations and distinguish between different level of driving difficulty. The goal was also to evaluate the ease of using a particular device, the availability of the associated software and the possibility of developing custom applications for these devices. The study involved 22 participants (of which 8 were female) between 18 and 45 years of age. Each had to pass three phases of measurement: baseline establishment (5 min), easy driving (5 min) and demanding driving (5 – 10 min). We compared the arithmetic mean of HRV samples, median, standard deviation of all R–R intervals (SDNN) and root mean square of successive differences (RMSSD) of HRV samples. The results showed that the Faros 360 device can detect statistically significant differences between easy and demanding driving and Empatica E4 device only the differences between baseline (hibernation) and movement. Noteable weakness of Empatica is that it does not detect every heart beat during movement and consequently gives incomplete measurement results. Nevertheless, due to the possibility of measuring the galvanic skin response (GSR) and a robust temperature sensor, Empatica E4 may in some cases prove to be a usable device. In the future we are performing an analysis of the measurements, separated by time intervals. We would like to detect short-term events, such as, for example, bumping, sudden breaking or collision.
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