Effects of Roadway Visibility on Steering Errors While Driving in Blowing Snow

Simulations of driving over a randomly-textured ground plane produce systematic steering errors when falling snow moves orthogonally to the driver's path (Dyre & Lew, 2005). Here, we examined whether these errors are mitigated by either high- or low-visibility roadways. Drivers viewed simulations of driving across a ground plane while snow moved at different speeds orthogonal to the initial direction of movement, which varies the angular distance between the focus of expansion (FOE) defined by the snow and the FOE defined by the environment. Drivers were instructed to steer such that they maintained a straight path relative to the ground. Three roadway visibility conditions were examined: no visible roadway, low-visibility roadway, and high-visibility roadway. Errors in steering and maintenance of lane position were related to the angular distance between the FOE for all roadway visibility conditions, although the magnitude of the errors lessened when low- and high-visibility roadways were present.