Browsing by Subject "gaze strategy"

This master’s thesis studies spontaneous gaze strategies when driving on a curved path. Methods used in many previous curve driving studies have not been sufficiently precise to differentiate between possible gaze strategies drivers use during cornering (Lappi, 2013, Itkonen et al. 2015). The methods in this thesis make it possible to differentiate between different gaze strategy predictions by comparing driver’s horizontal gaze velocity and half of car’s yaw rate. Waypoint hypothesis (WP), where gaze follows targets on the future path, predicts negative linear correlation and specific -1:1 ratio between horizontal gaze velocity and half of car’s yaw rate. Tangent point hypothesis (TP) and other travel point gaze strategies predict no correlation. In addition to previous study by Itkonen et al. (2015), the yaw rate is varied for quantitative analysis of the gaze behaviour and the experiment is conducted in two different environments, simulator and real test track, for reliability and validity. Gaze and car telemetry data was collected during a slow acceleration on a circular path in similar simulated (n=15) and real environment (n=4). As predicted by the WP hypothesis, the results show a very strong linear negative correlation between car’s half yaw rate and horizontal gaze velocity in simulator (-0.91) and strong linear negative correlation in test track (-0.75) and regression analysis shows slopes close to -1:1 ratio between the variables (simulator: -0.96 and test track: -0.79). The results can be clearly observed even on individual level. This suggests that primary gaze strategy when cornering in a curve is to pursue local flow on waypoints on the future path. The slight differences in results between simulator and test track experiment are discussed. These quantitative results contribute to making more precise models of driver behaviour, that can help advance autonomous car designs and driver-vehicle interaction models. The results also help to make gaze strategies and visuomotor process theories more measurable and comparable in different environments.