Analysis of the driver's stress level while driving in Truck Platooning

The logistic is interested by changes and truck manufacturers are investing in solutions such as truck platooning. This system leads to benefits (fuel consumption, safety, traffic efficiency). The paper presents the analysis of the psychophysical state of drivers during real tests in truck platooning. The peaks in the LF/HF (Low Frequency/High Frequency) parameter are considered, as they are linked to feelings of discomfort. Their occurrence may indicate whether the psychophysical state of the drivers is influenced by the different phases of driving in platoon. A method is defined to monitor and process the HRV (Heart Rate Variability) physiological parameter and the LF/HF ratio, based on the use of commercial smartwatches. An experimental activity, part of the European project C-Roads, allowed the collection of the physiological parameters of drivers and of the data featuring the vehicles in platoon. In general, the correlation between the two data sets revealed that drivers were not negatively affected by driving in platoon. The monitoring of the Follower driver, compared to the Leader, showed a higher level of stress. Peaks in the LF/HF parameter (i.e. high levels of stress) were associated in the 85 % of the cases to punctual situations that were expected to be stressful. Further possible applications of the method are presented, such as the investigation of the C-ITS impacts on the drivers.