Drivers' visual behavior when using handheld and hands-free cell phones.

Objective: This study investigated driver distraction and how the use of handheld (HH), portable hands-free (PHF), and integrated hands-free (IHF) cell phones affected the visual behavior of motor vehicle drivers.

Method: A naturalistic driving study recorded 204 participating drivers using video cameras and vehicle sensors for an average of 31 days. A total of 1564 cell phone calls made and 844 text messages sent while driving were sampled and underwent a video review.

Distracted driver performance to multiple alerts in a multiple-conflict scenario.

Objective: We investigated whether collision avoidance systems (CASs) should present individual crash alerts in a multiple-conflict scenario or present only one alert in response to the first conflict.

Background: Secondary alerts may startle, confuse, or interfere with drivers' execution of an emergency maneuver.

Method: Fifty-one participants followed a pickup truck around a test track.

Comparing handheld and hands-free cell phone usage behaviors while driving.

Objective: The goal of this study was to compare cell phone usage behaviors while driving across 3 types of cell phones: handheld (HH) cell phones, portable hands-free (PHF) cell phones, and integrated hands-free (IHF) cell phones. Naturalistic driving data were used to observe HH, PHF, and IHF usage behaviors in participants' own vehicles without any instructions or manipulations by researchers.

Methods: In addition to naturalistic driving data, drivers provided their personal cell phone call records.

The risk of a safety-critical event associated with mobile device use in specific driving contexts.

Objective: We explored drivers' mobile device use and its associated risk of a safety-critical event (SCE) in specific driving contexts. Our premise was that the SCE risk associated with mobile device use increases when the driving task becomes demanding.

Methods: Data from naturalistic driving studies involving commercial motor vehicle drivers and light vehicle drivers were partitioned into subsets representative of specific driving contexts.

Toward developing an approach for alerting drivers to the direction of a crash threat.

Objective: This study explored the potential for auditory and haptic spatial cuing approaches to alert drivers to the direction of a crash threat.

Background: For an automobile equipped with multiple crash avoidance systems, effective cuing of the crash threat direction may help the driver avoid the crash. Because the driver may not be looking in the direction of a visual crash alert, nonvisual crash alerts were explored as an additional means of directing attention to a potential crash situation.