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Browsing by Author "Wotring, Brian"

Now showing 1 - 10 of 10
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    Alcohol Intoxication Checklist: A Naturalistic Approach
    Wotring, Brian; Antin, Jonathan F.; Smith, Ryan C. (National Surface Transportation Safety Center for Excellence, 2021-07-16)
    This effort sought to determine the prevalence of particular visual and behavioral indicators for alcohol intoxication using data collected in the Strategic Highway Research Program 2 Naturalistic Driving Study (SHRP 2 NDS). A list of visual and behavioral cues was identified from previous research and served as the basis for identification. The prevalence of several of these cues reached statistical significance between judged states of intoxication. Some cues include, but are not limited to, lids-heavy, dozing, exhilarated, distracted, talkative, inability to sit upright, yawning, and leaning against window. While the study was able to determine the prevalence of the markers, several limitations temper interpretation. First, a large proportion of trips evaluated occurred between midnight and 4:00 a.m., when drivers are likely to be drowsy and exhibit many of the same visual and behavioral indicators also expected to be present in intoxicated individuals. Thus, impacts of drowsiness may be confounded with those of intoxication. In addition, the same visual cues were used both to determine the degree of intoxication as well as the behaviors most associated thereto, thus resulting in a logical conundrum. The results of this research should be viewed as exploratory work that can aid in the generation of hypotheses for future work.
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    Examining Senior Drivers Adaptation to Mixed Level Automated Vehicles: A Naturalistic Study
    Liang, Dan; Antin, Jonathan F.; Lau, Nathan; Stulce, Kelly E.; Baker, Stephanie Ann; Wotring, Brian (SAFE-D: Safety Through Disruption National University Transportation Center, 2019-08)
    Advances in the development of advanced vehicle technologies (AVTs), such as blind spot alerts, lane keep assist,lane alert, and adaptive cruise control, can benefit senior drivers by reducing exposure to hazards andcompensating for diminished cognitive abilities sometimes seen in this population. However, the degree to whichsuch benefits can be realized in this vulnerable population depends largely on the degree to which senior driverswill accept, adopt, and adapt to these features. This study investigated how 18 seniors, aged 70–79, accepted,trusted, and used mixed-function AVTs when provided an AVT-equipped vehicle to drive as they desired for a 6-week period. Researchers assessed attitudes and the effect of exposure via before-and-after exposure surveys, briefweekly check-in surveys during the driving exposure period, and focus group sessions conducted after theconclusion of the driving exposure period. Analyses revealed that seniors prefer technologies that inform, such asblind spot alert, over those that assert independent control over the vehicle, such as lane keep assist. Increasedconfidence in and willingness to use AVTs correlated positively with exposure, with adequate time for orientationand appropriate user documentation emerging as key factors determining senior drivers’ acceptance.
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    An Exploration of Driver Behavior During Turns at Intersections (for Drivers in Different Age Groups)
    Angell, Linda; Aitch, Sudipto; Antin, Jonathan F.; Wotring, Brian (National Surface Transportation Safety Center for Excellence, 2015-06-23)
    A two-phase study of driver behavior at intersections was conducted using a naturalistic paradigm. In Phase 1, the behavior of teen, middle-aged, and older drivers was compared for left turns at three types of left turns across path (LTAP) intersections. Phase II was a follow-on effort focused more narrowly on a single T-intersection that included both left and right turns. A data-mining algorithm was used to aggregate data from two different naturalistic databases to obtain instances of unprotected turns at the same intersection and instances from a comparison protected turn at a signalized intersection. Several dependent variables were analyzed, including visual scanning measures, head-turning measures, speed approaching and driving through the intersection, and gap acceptance and rejection times. Results from Phase 1 show that driver behavior differed between the unprotected turns and the comparison protected turn. The two types of unprotected turns also had different effects on scan patterns and glance durations through the initiation, conflict, and completion zones of the turn. Definitive age-group effects were seen with head turning. The Phase 1 results suggest that older drivers scanned more narrowly and that they strategically oriented their scans in the direction of greatest threat for certain types of unprotected left turns. Results from Phase 2 replicated those from Phase 1. For left turns, most driver groups had a similar distribution of glances by location for this T-intersection, with the forward-looking glances constituting almost half of all glances, followed by glances through the window areas. However, older drivers showed a higher proportion of glances to the right, indicating a strategic shift of attention that was consistent with the head-turn analysis in Phase 1. Link analyses done on the visual scan patterns of drivers indicated that older drivers and middle-aged drivers had more-organized and more-strategic visual scans of the intersection compared with young drivers. While middle-aged drivers and younger drivers scanned broadly, older drivers had a narrower scan that was oriented slightly toward the right for a left turn and to the left for a right turn, perhaps indicating attention to gap selection and threats in the stream of traffic into which they were merging. Visual entropy analyses showed that active visual scanning to a larger number of areas increased for all age groups when traffic was present. This increase was most pronounced for younger drivers. Significant differences were observed for peak speed and average speed during a left turn, with older drivers using lower speeds throughout intersections and completing their turns at lower speeds than other age groups. These findings suggest that the behavior of older drivers is at least partly strategic in nature. The changes in scanning exhibited by older drivers appear to be more focused “versions” of the visual scanning typical of middle-aged drivers, tuned specifically to areas of highest threat during turns. However, this may lead to some neglect of other areas, and it is possible that age-related changes in perception and cognition may be contributing to some of the differences.
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    Improving Mobility for Rural Older Adults: A Program Review
    Wotring, Brian; Antin, Jonathan F. (National Surface Transportation Safety Center for Excellence, 2020-08-07)
    The population of older adults is increasing and is expected to represent a larger proportion of the population over the next several decades. Those who live in rural areas face many transportation challenges, including a reliance on personal vehicles, reduced availability of public transportation, fewer friends and family to rely on for rides, and longer travel distances. This research effort entailed expert interviews and a search to determine what types of programs currently exist in rural or urban environments that might enable rural seniors to retain mobility. The results illustrate a wide variety of programs, many of which offer multiple types of services. Among these, there are also minute but important differences. Several gaps between users requiring rides and available mobility options for seniors are noted. Suggestions for an implementation to bridge the gap are explored. Researchers discovered that many law enforcement training programs appear to no longer be functional. Additionally, gaps related to the use of GPS technologies as well as expansions of current implementations are discussed.
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    In-vehicle device acquisition and usage in personal vehicles : commercial versus non-commercial driver's license holders
    Wotring, Brian; Angell, Linda; Antin, Jonathan F. (National Surface Transportation Safety Center for Excellence, 2011-03-28)
    A survey was administered to 1,524 Virginia Tech faculty, staff, and students and Blacksburg Transit drivers in an effort to differentiate between commercial driver's license holders (72 of the respondents) and "regular" (i.e., non-commercial) drivers in terms of their ownership and personal in-vehicle usage of handheld devices (e.g., cell phones and MP3 players). Results indicated that discrepancies exist between these two groups for some devices and usage. For instance, almost 35% of commercial drivers reported that they "never" text while driving their personal vehicles compared with only 4% of the non-commercial drivers.
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    Investigating Lane Change Behaviors and Difficulties for Senior Drivers Using the SHRP 2 Naturalistic Database
    Antin, Jonathan F.; Wotring, Brian; Perez, Miguel A.; Glaser, Daniel (National Surface Transportation Safety Center for Excellence, 2017-10-19)
    Older drivers are more likely to be involved in a lane change crash compared with middle-aged drivers. While a number of different blind spot warning systems and intervention systems exist, a more thorough understanding of in situ lane change behaviors and difficulties for older drivers may be beneficial to inform future lane-change support systems and the development or improvement of related training modules. This effort examined lane-change behavior and glance locations for three age groups, younger (18–29 years), middle-aged (30–49 years), and older drivers (70–94 years), using data from the Second Strategic Highway Research Program (SHRP 2) Naturalistic Driving Study (NDS). Descriptive outcomes were reported for several glance characteristics, including glance duration and percentage of time, as well as entropy as a measure of glance dispersion. Various behaviors, including turn signal use, glance errors, and environmental characteristics, were analyzed. For both uninterrupted and interrupted lane changes, results showed that many drivers, regardless of age, failed to make over-the-shoulder (OTS) and side mirror glances prior to initiating the lane change. Most drivers relied on side mirror and rearview mirror checks for lane change safety. Many drivers failed to check the side mirror prior to initiating the lane change maneuver. In addition, many drivers failed to activate the turn signal prior to lane change initiation, and only approximately 60% of older drivers activated the signal at any point during the lane change. For uninterrupted lane changes, when a conflict did occur with relation to the lane change maneuver, it was most frequently associated with either a lead vehicle in or a lead vehicle incurring into the destination lane. Results for interrupted lane changes showed that when a conflict did occur with relation to the lane change maneuver, it was most frequently associated with two sources of conflict: lead vehicle in or incurring into the destination lane or a trailing vehicle in or incurring into the destination lane. Left lane changes also showed a moderate level of conflict with adjacent vehicles in or incurring into the destination lane. Nearly one-third of interrupted lane change maneuvers involved an event where the participant proceeded despite improper spacing and cut off a trailing vehicle in the destination lane. As driver age increases, the percentage of events where the driver cut off another vehicle increases: while younger drivers cut off another vehicle 19% of the time, middle-aged drivers did so 27% of the time, and older drivers 28% of the time.
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    An On-Road Evaluation of the Impact of Explicit and Implicit Cognitive Training Protocols on Safety-Related Senior Driver Behaviors
    Antin, Jonathan F.; Owens, Justin M.; Wotring, Brian (National Surface Transportation Safety Center for Excellence, 2017-04-21)
    This study presents a long-term examination of the effects of two types of perceptual-cognitive brain training programs on senior driver behavior and on-road driving performance. Seniors over the age of 69 engaged in either a Toyota-designed in-vehicle training program based on implicit learning principles or a commercially available computer-based training program developed by Posit Science®. Another group served as a control group and received no training; total enrollment was 55 participants. Participants completed a series of four experimental sessions: (1) baseline pre-training, (2) immediate post-training, (3) 6–9 months post-training, and (4) 12–16 months post-training. Experimental metrics taken at each session included a laboratory metrics portion, a target-detection performance on a closed-road course, and a public-road portion examining vehicle control and glance behavior. These sessions were designed to examine not only whether training provided immediate benefit to senior drivers, but also whether any improvements persisted after training or precluded decrements in performance found in untrained individuals. The results found few statistically significant improvements in performance with either type of training. However, there were non-significant trends toward improved glance behavior at risky intersections for participants in the Car Training group, suggesting that this might be a valuable target of future research using experimental designs with increased statistical power. In addition, several tests of training improvements examined by individual differences suggested that drivers with particular deficits on physical and cognitive metrics could benefit differentially from this type of training, leading to future research questions on appropriate targeting and the potential benefits of refresher training.
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    Pedestrian-Vehicle Interaction Data Dictionary and Analysis Protocol: Design, Development, and Pilot Application on Two Naturalistic Driving Databases
    Mabry, J. Erin; Wotring, Brian; McClafferty, Julie A.; Soccolich, Susan A.; Boucher, Ben (2024-08-09)
    Pedestrian conflicts with vehicles continue to be a serious problem in the United States. Unlike vehicle occupants, pedestrians do not have the protection of airbags, a steel structure surrounding them, or other vehicle safety technologies; their resultant vulnerability places them at higher risk of injury when involved in a traffic crash or conflict. Examining pedestrian behavior in a variety of settings and interaction severity levels supports research goals to improve pedestrian safety. The goals of this study were to: 1. Create an inclusive dictionary of video data analysis variables that details and describes interactions between pedestrians and motorized vehicles; and 2. Develop and pilot test a Pedestrian-Vehicle Interaction Data Reduction Protocol (PVIP) using existing naturalistic driving datasets. Implementing the PVIP confirmed that coding elements related to the interaction response between the pedestrian and vehicle from each perspective, and according to the three epoch stages (i.e., leading up to, during, and following the interaction), was critical for characterizing the entire interaction with consideration of all viewpoints. Pedestrian behaviors, locations, communication strategies, distractions, impairments, and glance behaviors were observed and coded at each stage of the epoch to account for behavioral, sensory-related, and positional changes of the pedestrian occurring over the course of the interaction that could impact the outcome. Similarly, coding the vehicle maneuver, driver behaviors, driving-related tasks, and glance behavior across the interaction epoch may be important elements to consider for pedestrian safety. Pedestrian location across the epoch was also an important variable in the pilot analyses. This study is the first of its kind to design, develop, and systematically apply a comprehensive, video-based, and pedestrian-centric data reduction protocol to NDS data to explore and describe interactions between pedestrians and vehicles for better understanding of pedestrian safety. The output of this project is a comprehensive and systematic PVIP that can be used to characterize pedestrian-vehicle interactions and behaviors. The protocol is organized so that researchers may select questions or groups of questions that are applicable for their specific research objectives in an à la carte fashion to create a focused protocol that fully explores a pedestrian-vehicle scenario using available data.
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    SmartShield: A Proof-of-Concept Application for Augmented Reality in Driving Research
    Owens, Justin; Kavanaugh, Daniel; Wotring, Brian (National Surface Transportation Safety Center for Excellence, 2022-09-16)
    Driver behavior research has traditionally been conducted using varied modalities ranging from controlled experimental research to naturalistic observation, all of which face fundamental trade-offs among realism, control, and the maintenance of a safe environment for both drivers and other road users. New technology, particularly virtual and augmented reality (VR and AR, respectively), present opportunities for improving this balance by potentially enabling the merging of virtual, controlled stimuli with real-world driving. If such experimental tools could be developed, they have the potential to revolutionize behavioral research by combining the experimental control and safety of simulation research with the validity of on-road or test-track studies where participants drive physical vehicles in the real world. The current effort was undertaken as a proof-of-concept challenge to implement AR glasses as a tool for driver behavior research. Researchers conducted a comprehensive review of current offerings in the AR and VR spaces and selected the candidate most likely to succeed, the Microsoft HoloLens. The HoloLens is a lightweight, head-mounted visor that combines a direct view of the world with an overlaid virtual image. As designed, the system is intended to provide support for indoor tasks in relatively static environments, such as supporting visualization in engineering and health care fields. In these controlled environments, onboard software creates three-dimensional images of persistent virtual objects that can interact with real-world surfaces using a series of cameras and positioning sensors. In theory, such technology could be extended to superimpose virtual objects onto the driving scene, the exploration of which formed the premise of this project. Following procurement of the device, the team developed virtual objects within the Unity environment and investigated a variety of methods to overlay those objects in the real world. The process proved difficult with several challenges, including flickering and/or drifting objects, a lack of contrast in sunlight, incompatibility with externally provided GPS coordinates, and unacceptable visual range. Given that the HoloLens was intended for use in an indoor environment, relocating it to an outdoor environment revealed its limitations. While indoor performance in lower light was promising, the display was unable to compensate for the intense sunlight, and the device’s internal GPS receiver did not function at a level required for research, resulting in objects being displayed in incorrect ways. The team was able to demonstrate that the goal of using augmented reality in research is possible, but not with currently available technology. Future research should focus on utilizing newer designs with more suitability to be used outdoors in direct sunlight and at longer ranges.
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    Speed Management Countermeasures: Gaps and Opportunities
    Wotring, Brian; Medina, Alejandra; Antin, Jonathan F. (National Surface Transportation Safety Center for Excellence, 2023-02-01)
    The number of speeding-related crashes continues to be a major concern on U.S. highways, with 29% of roadway fatalities determined to be due to speeding (National Center for Statistics and Analysis, 2022). To reduce the number of fatalities and move towards a goal of zero roadway deaths, it is important to understand the risks and factors that lead to speeding behaviors as well as to evaluate currently deployed speeding countermeasures. In order to determine the state of speeding countermeasures, a highly targeted literature review was focused on published documentation from national agencies and the peer-reviewed literature. These specific sources were chosen to rely solely on the highest quality countermeasure information currently available. Using these sources, a gap analysis was then completed based on statements and postulations within the noted literature. Additionally, the research team engaged in a brainstorming session to determine additional gaps and potential opportunities for improved countermeasure implementation not yet represented in the formal literature. Finally, the research team also collected information on several speeding campaigns and initiatives currently in place. In order to better organize the findings, they were grouped by domain. Such groups include advanced technologies, education and outreach, enforcement, engineering, and other. Overall, the review of documentation on speeding countermeasures revealed a large number of gaps and opportunities in the current knowledge space. One benefit of housing so many in a single location is to aid in the process of hypothesis generation. This collection may prove useful in guiding or eliciting future ideas.