Rational truck driving and its correlated driving features in extra-urban areas

Truck drivers typically display different behaviors when facing various driving events, e.g., approaching a roundabout, and thereby have a major impact both on the fuel consumption and the vehicle speed. Within the context where fuel is increasingly a major cost center for merchandise transport companies, it is important to recognize different driver behaviors in order to be able to simulate them as closely to the real data as possible during the truck development process. In this paper, we introduce, instead of economic driving, the notion of rational driving which seeks to decrease the average fuel consumption while respecting the transport companies' constraint, i.e., the delivery delay. Moreover, we also propose an indicator, namely rational driving index (RDI), which enables to quantify how good a driver behavior is with respect to the rational driving. We then investigate various driving features contributing to characterize a rational driver behavior, using real driving data collected from 34 different truck drivers on an extra-urban road section particularly representative of travel paths of trucks ensuring regional merchandise distribution. Given the fact that real driving data collected on an open road can differ in terms of environment, e.g., weather, traffic, we further study, through simulations on a digital representation of a roundabout, the impact of two major driving features, i.e., the use of coasting and crossing speed at roundabouts, with respect to rational driving. The experimental results from both real driving data and simulations show high correlations of these two driving features with respect to RDI and demonstrate that a good rational driver tends to decelerate slowly during braking periods (use of coasting) and have high crossing speed in roundabouts.