Objective: Right-of-way negotiation between drivers and pedestrians often relies on explicit (e.g., waving) and implicit (e.
View Article and Find Full Text PDFObjective: Advanced driver assistance systems are increasingly available in consumer vehicles, making the study of drivers' behavioral adaptation and the impact of automation beneficial for driving safety. Concerns over driver's being out-of-the-loop, coupled with known limitations of automation, has led research to focus on time-critical, system-initiated disengagements. This study used real-world data to assess drivers' response to, and recovery from, automation-initiated disengagements by quantifying changes in visual attention, vehicle control, and time to steady-state behaviors.
View Article and Find Full Text PDFObjective: This paper characterizes the actions of pedestrian-driver dyads by examining their interdependence across intersection types (e.g., zebra crossings, stop signs).
View Article and Find Full Text PDFSpeeding is a prevalent and complex risky behavior that can be affected by many factors. Understanding how drivers speed is important for developing countermeasures, especially as new automation features emerge. The current study seeks to identify and describe types of real-world speeding behaviors with and without the use of partial-automation.
View Article and Find Full Text PDFObjective: Adaptive cruise control (ACC) and lane centering are usually marketed as convenience features but may also serve a safety purpose. However, given that speeding is associated with increased crash risk and worse crash outcomes, the extent to which driver's speed using ACC may reduce the maximum safety benefit they can obtain from this system. The current study was conducted to characterize speeding behavior among drivers using adaptive cruise control and a similar system with added lane centering.
View Article and Find Full Text PDFObjective: We present a model for visual behavior that can simulate the glance pattern observed around driver-initiated, non-critical disengagements of Tesla's Autopilot (AP) in naturalistic highway driving.
Background: Drivers may become inattentive when using partially-automated driving systems. The safety effects associated with inattention are unknown until we have a quantitative reference on how visual behavior changes with automation.
Background: The emergence of partial-automation in consumer vehicles is reshaping the driving task, the driver role, and subsequent driver behavior. When using partial-automation, drivers delegate the operational control of the dynamic driving task to the automation system, while remaining responsible for monitoring, object/event detection, response selection, and execution. Hence, driving has become a collaboration between driver and automation systems that is characterized by dynamic Transfers of Control (TOC).
View Article and Find Full Text PDFVoice interfaces reduce visual demand compared with visual-manual interfaces, but the extent depends on design. This study compared visual demand during baseline driving with driving while using voice or manual inputs to place calls with Chevrolet MyLink, Volvo Sensus, or a smartphone. Mean glance duration and total eyes-off-road-time increased when using manual input compared with baseline driving; only eyes off road time increased with voice input.
View Article and Find Full Text PDF. Understanding the cognitive load of drivers is crucial for road safety. Brain sensing has the potential to provide an objective measure of driver cognitive load.
View Article and Find Full Text PDFModern digital interfaces display typeface in ways new to the 500 year old art of typography, driving a shift in reading from primarily long-form to increasingly short-form. In safety-critical settings, such at-a-glance reading competes with the need to understand the environment. To keep both type and the environment legible, a variety of 'middle layer' approaches are employed.
View Article and Find Full Text PDFHow quickly can a driver perceive a critical hazard on or near the road? Evidence from vision research suggests that static scene perception is fast and holistic, but does this apply in dynamic road environments? Understanding how quickly drivers can perceive hazards in moving scenes is essential because it improves driver safety now, and will enable autonomous vehicles to work safely with drivers in the future. This paper describes a new, publicly available set of videos, the Road Hazard Stimuli, and a study assessing how quickly participants in the laboratory can detect and correctly respond to briefly presented hazards in them. We performed this laboratory experiment with a group of younger (20-25 years) and older (55-69 years) drivers, and found that while both groups only required brief views of the scene, older drivers required significantly longer to both detect (220 ms, younger; 403 ms, older) and correctly respond to hazards (388 ms younger; 605 ms older).
View Article and Find Full Text PDFIf a vehicle is driving itself and asks the driver to take over, how much time does the driver need to comprehend the scene and respond appropriately? Previous work on natural-scene perception suggests that observers quickly acquire the gist, but gist-level understanding may not be sufficient to enable action. The moving road environment cannot be studied with static images alone, and safe driving requires anticipating future events. We performed two experiments to examine how quickly subjects could perceive the road scenes they viewed and make predictions based on their mental representations of the scenes.
View Article and Find Full Text PDFThe impact of using a smartwatch to initiate phone calls on driver workload, attention, and performance was compared to smartphone visual-manual (VM) and auditory-vocal (AV) interfaces. In a driving simulator, 36 participants placed calls using each method. While task time and number of glances were greater for AV calling on the smartwatch vs.
View Article and Find Full Text PDFThe relationship between a driver's glance orientation and corresponding head rotation is highly complex due to its nonlinear dependence on the individual, task, and driving context. This paper presents expanded analytic detail and findings from an effort that explored the ability of head pose to serve as an estimator for driver gaze by connecting head rotation data with manually coded gaze region data using both a statistical analysis approach and a predictive (i.e.
View Article and Find Full Text PDFBackground: Much of the driver distraction and inattention work to date has focused on concerns over drivers removing their eyes from the forward roadway to perform non-driving-related tasks, and its demonstrable link to safety consequences when these glances are timed at inopportune moments. This extensive literature has established, through the analyses of glance from naturalistic datasets, a clear relationship between eyes-off-road, lead vehicle closing kinematics, and near-crash/crash involvement.
Objective: This paper looks at the role of driver expectation in influencing drivers' decisions about when and for how long to remove their eyes from the forward roadway in an analysis that consider the combined role of on- and off-road glances.
Previous literature has shown that vehicle crash risks increases as drivers' off-road glance duration increases. Many factors influence drivers' glance duration such as individual differences, driving environment, or task characteristics. Theories and past studies suggest that glance duration increases as the task progresses, but the exact relationship between glance sequence and glance durations is not fully understood.
View Article and Find Full Text PDFPsychophysical research on text legibility has historically investigated factors such as size, colour and contrast, but there has been relatively little direct empirical evaluation of typographic design itself, particularly in the emerging context of glance reading. In the present study, participants performed a lexical decision task controlled by an adaptive staircase method. Two typefaces, a 'humanist' and 'square grotesque' style, were tested.
View Article and Find Full Text PDFObjective: Research has established that long off-road glances increase crash risk, and other work has shown increased off-road glance behavior in older drivers. This study investigated the relationship between older drivers' (M = 66.3, range 61-69 years) cognitive abilities and the duration of off-road glances while engaged in secondary visual-manual activities.
View Article and Find Full Text PDFThe relative impact of using a Google Glass based voice interface to enter a destination address compared to voice and touch-entry methods using a handheld Samsung Galaxy S4 smartphone was assessed in a driving simulator. Voice entry (Google Glass and Samsung) had lower subjective workload ratings, lower standard deviation of lateral lane position, shorter task durations, faster remote Detection Response Task (DRT) reaction times, lower DRT miss rates, and resulted in less time glancing off-road than the primary visual-manual interaction with the Samsung Touch interface. Comparing voice entry methods, using Google Glass took less time, while glance metrics and reaction time to DRT events responded to were similar.
View Article and Find Full Text PDFThere is limited research on trade-offs in demand between manual and voice interfaces of embedded and portable technologies. Mehler et al. identified differences in driving performance, visual engagement and workload between two contrasting embedded vehicle system designs (Chevrolet MyLink and Volvo Sensus).
View Article and Find Full Text PDFDevelopments in lighting technologies have allowed more dynamic digital billboards in locations visible from the roadway. Decades of laboratory research have shown that rapidly changing or moving stimuli presented in peripheral vision tends to 'capture' covert attention. We report naturalistic glance and driving behavior of a large sample of drivers who were exposed to two digital billboards on a segment of highway largely free from extraneous signage.
View Article and Find Full Text PDFDrivers' reactions to a semi-autonomous technology for assisted parallel parking system were evaluated in a field experiment. A sample of 42 drivers balanced by gender and across three age groups (20-29, 40-49, 60-69) were given a comprehensive briefing, saw the technology demonstrated, practiced parallel parking 3 times each with and without the assistive technology, and then were assessed on an additional 3 parking events each with and without the technology. Anticipatory stress, as measured by heart rate, was significantly lower when drivers approached a parking space knowing that they would be using the assistive technology as opposed to manually parking.
View Article and Find Full Text PDFOne purpose of integrating voice interfaces into embedded vehicle systems is to reduce drivers' visual and manual distractions with 'infotainment' technologies. However, there is scant research on actual benefits in production vehicles or how different interface designs affect attentional demands. Driving performance, visual engagement, and indices of workload (heart rate, skin conductance, subjective ratings) were assessed in 80 drivers randomly assigned to drive a 2013 Chevrolet Equinox or Volvo XC60.
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