Investigating the impact of context and environment on driver’s situation awareness

The objective of this study is to assess drivers’ ability to detect objects and the trajectory of these objects in scenarios with different environmental complexity levels. This is examined in the context of situation awareness (SA), defined as the perception, comprehension and projection of the environmental properties and positions. The Situation Awareness Global Assessment Technique (SAGAT) was used in a video-based driving simulation study, where participants were asked to mark all objects in the order of perceived risk and select the corresponding object type. This provided spatially continuous SA responses for the objects of interest (i.e., pedestrians, cars and cyclists). The findings showed that object type and size, visual complexity, number of objects and roadway type had a significant impact on the operator’s ability to perceive objects as well as to project the object trajectories. The results provide us some insights in choosing predictors besides eye-tracking data for SA predictive model.