Analysis of Lane-Change Crashes and Near-Crashes

摘要

This report examines driver behaviors leading to lane-change crashes and near-crashes using data from the 100-Car Naturalistic Driving Study (Dingus, Klauer, Neale, et al., 2006) that unobtrusively examined 241 participants as they drove their personal vehicles during their daily commutes in the Northern Virginia/Washington, DC, area for a period of 12 to 13 months each. The study identified 135 lane-change events, of which 3 were crashes and the rest near-crashes. The analysis of these events found that 85 percent of the drivers used their turn signals during planned left-lane changes, while 24 percent used their turn signals when making unplanned left-lane changes to avoid a forward crash threat. The study found that 46 percent of the drivers looked toward their left mirrors, 50 percent looked toward their left windows, and 17 percent looked toward their center mirrors during the 3 s prior to performing planned left-lane changes. Furthermore, significantly fewer drivers sampled their mirrors when swerving into adjacent lanes to avoid forward crash threats. It was also found that drivers making planned left-lane changes took an average of 1.5 s to cross into the adjacent left lanes. An average of 2.3 s elapsed before these drivers encountered a lane-change near-crash. These findings suggest that drivers had little time to avoid an event once they started to change lanes. The majority of the near-crashes were resolved by drivers braking and steering away from the crash threat (compared to just braking, or just steering away). The 100-Car Study shows that safe driving requires drivers to concurrently monitor the forward roadway and surrounding traffic. However, drivers are limited in that they can visually attend to only one location at a time. Safely monitoring ones surroundings may be difficult in dense traffic conditions. Systems that assist drivers in perceiving adjacent vehicles and recognizing crash threats while concurrently monitoring the forward roadway may mitigate this human factors dilemma.