Browsing by Author "Petersen, Christine Marie"

Now showing 1 - 2 of 2
  • Thumbnail Image
    Item
    Effect of Cyclists' Communication Cues on Drivers' Perceptions of Intent
    (2023-10-23) Petersen, Christine Marie; DeLucia, Patricia R
    Background: There has been an increase in the number of fatal crashes between cyclists and drivers over the last decade. One potential cause of collisions between these road users is a driver’s inability to correctly predict a cyclist’s intentions. The current research aimed to determine what cues drivers used to make correct judgments of intent and assessed where drivers looked when asked to make judgments of intent. Methods: Drivers were shown video clips of a cyclist performing different combinations of cues (position on the road, head movement, arm signals). They were asked to report what they believed the cyclist intended to do (i.e., turn left, turn right, stop, or go straight). The scene ended before the cyclist performed the intended action. After the driver made their decision, they were asked to describe to the experimenter what cues they used to make their decision. Results: The results revealed that the likelihood of a driver correctly predicting the cyclist’s intentions depended only on the arm signal presented and not on head movement or position on the road. The straight arm signals were the only signals correctly predicted by all drivers. Less than a quarter of the drivers correctly predicted the bent right turn arm signal. Results of eye movement measures also showed that drivers directed their attention to the back of the cyclist and then redirected their attention to where a signal was being presented. Conclusion: Overall, drivers could correctly predict a cyclist’s intentions when straight arm signals were presented. Transportation laws should be rewritten to remove the bent right turn arm signal to improve cyclists' safety.
  • Thumbnail Image
    Item
    Influence of Auditory Information on Drivers’ Abilities to Extrapolate Motion of a Lead Vehicle in a Traffic Environment
    (2025-04-16) Petersen, Christine Marie; DeLucia, Patricia
    Nearly 29 percent of all traffic collisions between two vehicles on the road are rear-end collisions, primarily caused by shortened headway. This shortened headway could be attributed to a driver’s inability to accurately extrapolate motion. Components of music, such as tempo, may affect drivers' abilities to extrapolate motion, but it has not yet been studied. This is important to understand, as about 70% of Americans listen to music while driving. Therefore, the current research aimed to understand whether music, specifically the tempo, affects drivers' abilities to extrapolate motion. Drivers watched simulated car-following scenes and either heard no sound or a sound with a slow or fast tempo. After an interruption, the scene reappeared with the lead vehicle at the correct position or at a more or less advanced position. Drivers reported whether the lead vehicle reappeared at the correct position. The first experiment examined if drivers' abilities to extrapolate motion during a 777 ms interruption varied based on the type of sound played while the driver drove the same speed, faster, or slower than the lead vehicle (i.e., relative velocity). The second experiment examined if the timing of sound (played during the entire scene including the interruption, only before the interruption, or only during the interruption) influenced motion extrapolation and whether a 3.2 s interruption duration affected drivers' reappearance judgments when the driver drove faster than the lead vehicle. Motion extrapolation at an interruption of 777 ms was based only on the relative velocity of the vehicles in the scene. The effect of tempo was not significant. When the interruption was 3.2 s, the tempo influenced drivers' abilities to extrapolate motion. Specifically, judgments were more biased towards advanced reappearance positions at a faster tempo compared to a slower tempo. When the interruption duration was 3.2 s but not 777 ms, drivers relied on the auditory stimuli, resulting in a greater difference in reappearance judgments among sound conditions. Thus, auditory information can affect drivers' abilities to extrapolate motion, but only at relatively longer interruptions.