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Motor vehicle crashes involving child Vulnerable Road Users (VRUs) remain a critical public health concern in the United States. While previous studies successfully utilized the crash scenario typology to examine traffic crashes, these studies focus on all types of motor vehicle crashes thus the method might not apply to VRU crashes. Therefore, to better understand the context and causes of child VRU crashes on the U.S. road, this paper proposes a multi-step framework to define crash scenario typology based on the Fatality Analysis Reporting System (FARS) and the Crash Report Sampling System (CRSS). A comprehensive examination of the data elements in FARS and CRSS was first conducted to determine elements that could facilitate crash scenario identification from a systematic perspective. A follow-up context description depicts the typical behavioral, environmental, and vehicular conditions associated with an identified crash scenario.

There is a strong evidence that the overrepresentation of teen drivers in motor vehicle crashes is mainly due to their poor hazard perception skills, i.e., they are unskilled at appropriately detecting and responding to roadway hazards. This study evaluates two cuing systems designed to help teens better understand their driving environment. Both systems use directional color-coding to represent different levels of proximity between one’s vehicle and outside agents. The first system provides an overview of the location of adjacent objects in a head-up display in front of the driver and relies on drivers’ focal vision (focal cuing system). The second system presents similar information, but in the drivers’ peripheral vision, by using ambient lights (peripheral cuing system). Both systems were retrofitted into a test vehicle (2014 Toyota Camry). A within-subject experiment was conducted at the University of Michigan Mcity test-track facility.

Mcity at the University of Michigan in Ann Arbor provides a realistic off-roadway environment in which to test vehicles and drivers in complex traffic situations. It is intended for testing of various levels of vehicle automation, from advanced driver assistance systems (ADAS) to fully self-driving vehicles. In a recent human factors study of interfaces for teen drivers, we performed parallel experiments in a driving simulator and Mcity. We implemented driving scenarios of moderate complexity (e.g., passing a vehicle parked on the right side of the road just before a pedestrian crosswalk, with the parked vehicle partially blocking the view of the crosswalk) in both the simulator and at Mcity.

Body-color brake lamps are lamps that in their off state match the body color of the car. When energized, all body-color lamps, as well as conventional lamps, appear bright red. The speed of response to a body-color brake lamp may differ from the speed of response to a conventional lamp for two reasons. The first is that the difference between off-and on-state luminances varies primarily with off-state luminance. When the difference is larger than for the conventional lamp, the increased luminance contrast may speed reaction time. The other reason that responses for the two types of lamps may differ is the greater chromaticity contrast that body-color lamps have between their on and off states. This study separately evaluated the effects of luminance contrast and chromaticity contrast for body-color brake lamps.

In two experiments, we examined the possibility that rearview mirror reflectivity influences drivers' perceptions of the distance to following vehicles. In the first experiment, subjects made magnitude estimates of the distance to a vehicle seen in a variable-reflectance rearview mirror. Reflectivity had a significant effect on the central tendency of subjects' judgments: distance estimates were greater when reflectivity was lower. There was no effect of reflectivity on the variability of judgments. In the second experiment, subjects were required to decide, under time pressure, whether a vehicle viewed in a variable-reflectance rearview mirror had been displaced toward them or away from them when they were shown two views of the vehicle in quick succession. We measured the speed and accuracy of their responses. Mirror reflectivity did not affect speed or accuracy, but it did cause a bias in the type of errors that subjects made.