729 research outputs found
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Formulation of Driver Judgment Process around Curves for Deviated State Detection
No full textThe objective of this study is to propose indices that detect deviated states of drivers during driving considering their judgment process and using a road environment and natural driving behavior database. To this end, we focus on curved roads because as road curvature changes continuously drivers need to adapt their behavior to not go wide of the lane or the road. The drivers’ speed choice behavior around curve situations was focused upon, and a speed choice process was formulated. Moreover, the validity of the formulated speed choice behavior in curve situations was examined using the real vehicle and the simulato
Measuring Young Drivers’ Behaviors during Complex Driving Situations
No full textDriving behaviors of teenagers and adults in complex driving situations, viz., merges and intersections, from an 18-month longitudinal naturalistic driving study were analyzed. Variables from multiple sources were selected to create an Unsafe Driving Index to rate drivers’ behaviors in these locations. Teenagers scored lower on this index, corresponding to safer driving behaviors, than adults. However, the teenagers’ scores for the index increased across the study period. The interpretations of these findings are discussed with respect to the methodological aspects of the study and in terms of driver training and rule following
The Effects of Momentary Visual Disruption on Hazard Anticipation in Driving
No full textDriver distraction is known to increase crashes, especially when the driver glances for especially long periods of time inside the vehicle. While it is clear that such glances increase risk for the driver when looking inside the vehicle, it is less clear how these glances disrupt the ongoing processing of information outside the vehicle once the eyes return to the road. The present study was aimed at exploring the effect of visual disruptions on the top-down processes that guide the detection and monitoring of hazards on the forward roadway. Using a driving simulator, twelve participants were monitored with an eye tracking system while they navigated various hazardous scenarios. Six participants were momentarily interrupted by a visual secondary task (simulating a glance inside the vehicle) prior to the hazard occurrence and six were not. Eye movement analyses show that interrupted drivers often failed to continue scanning for a hazard when their forward view reappeared. Implications of this study are discussed
A Research Synthesis of Text Messaging and Driving Performance
No full textTo determine the effects of text messaging on driving performance, all available experimental studies that measured driving performance were identified through a variety of database searches and backtracking strategies, and analyzed using standard research synthesis methods. Fourteen studies with a total of 519 participants were coded and analyzed. Methodology, independent and dependent variables, and statistical analyses varied widely across studies, but conclusions were clear and convergent. Reaction time, crashes, longitudinal and lateral control, eye movements, hazard detection and subjective workload measures indicate significant decrements in driving performance while reading and typing text messages. The importance of the results for further policy development and methodological reporting is briefly introduced
Can Young Drivers Learn to Anticipate Hidden Hazards: A Driving Simulator Study
No full textModern technology makes possible improvements in training programs designed to develop young drivers’ abilities to anticipate hazardous situations. These improvements which come from increases in the range of scenarios to which young drivers are exposed and the number of times young drivers can practice the skills they are learning. In this study, a new Flash-based, PC training program that runs on the web, Road Aware® (RA), is evaluated using a driving simulator. The program was developed by State Farm. Twenty-four young trained drivers and twenty four young untrained drivers were asked to drive various simulated hazardous scenarios while their gaze was monitored by an eye tracking system. The results show that trained drivers were more likely to anticipate hazards than their untrained peers, a difference which was present for both near transfer (scenarios that appeared in training) and far transfer scenarios. The effectiveness of RA is compared with other hazard anticipation training programs that were evaluated on a driving simulator and in the field. It appears every bit as effective in general and more effective for some scenarios. Additionally, there is evidence suggesting that, for the first time, young drivers can be trained to anticipate hazards as well as drivers who are older and more experienced
“Choking Under Pressure” in Older Drivers
No full textAging can impair executive control and emotion regulation, affecting driver decision-making and behavior, especially under stress. We used an interactive driving simulator to investigate ability to make safe left-turns across oncoming traffic under pressure in 13 older (> 65 years old) and 16 middle-aged (35-56 years old) drivers. Drivers made left-turns at an uncontrolled intersection with moderately heavy oncoming traffic. Gaps between oncoming vehicles varied and increased gradually from 2 s to 10 s. Drivers made two left-turns with a vehicle honking aggressively behind (pressure condition), and two left-turns without the honking vehicle (control condition). Results showed that middle-aged drivers made more cautious turning decisions under pressure (by waiting for larger and safer gaps, p < .001), but older drivers did not. Further, older driver turning paths deviated under pressure compared to the control condition (p < .05), but the middle-aged group did not. Moreover, across all subjects, better executive function was significantly correlated with larger increases of accepted gap size from control to honking (p < .01). The findings suggest that older drivers are more sensitive to traffic challenges from environmental pressure and that neural models of older driver performance and safety must factor in age-related changes in executive control and emotion processing
An Initial Assessment of the Significance of Task Pacing on Self-Report and Physiological Measures of Workload While Driving
No full textIn block A of a simulator study, a sample of 38 drivers showed a stepwise increase in heart rate and skin conductance level (SCL) from single task driving and across 3 levels of an auditory presentation – verbal response dual task (n-back), replicating findings from on-road research. Subjective ratings showed a similar stepwise increase, establishing concurrent validity of the physiological indices as measures of workload. In block B, varying the inter-stimulus interval in the intermediate 1-back level of the task resulted in a pattern across self-report workload ratings, heart rate, and SCL suggesting that task pacing may influence effective workload. Further consideration of the impact of task pacing in auditoryverbal in-vehicle applications is indicated
Driver Distraction through Conversation Measured with Pupillometry
No full textAssessing a driver´s mental workload during tasks that are not visualmanual is a challenging endeavor. Especially with the rapid development of speech systems, this is becoming increasingly important. Pupillometry promises to be a suitable physiological measurement method, sensitive to variations of cognitive workload. This driving simulator study shows that the pupillometry data indicate a significant increase in cognitive activity during conversation tasks regardless of the acoustic channel used
How Missing a Treatment of Mixed Amphetamine Salts Extended Release Affects Performance in Teen Drivers with ADHD
No full textMixed Amphetamine Salts Extended Release (MAS-XR or Adderall XR®) is a stimulant medication used to control symptoms of ADHD. People occasionally fail to take their medications. The goal of this pilot study was to assess the impact of a single missed medication on driving performance in 14 teen drivers with ADHD mixed type as a function of driving skill. A double-blind placebo control crossover design was used and participants were tested in a driving simulator. On the evening of the first day, baseline measures of driving performance were taken to assess driving skills (on medication). Then on two consecutive days drivers were tested three times a day, one day on medication and the other day off. Results indicated increased collisions and hazard response time off medication, with performance worst on 36 hours post-medication. Participants with the least developed driving skills benefited most from medication. This highlights the importance of consistent medication use in inexperienced teen drivers with ADHD
Neuropsychological Predictors of Safety in Urban Left-Turn Scenarios
No full textLeft turns at urban intersections can be dangerous, especially when views are obstructed or pedestrians are present. Impairments in driver vision, motor, and cognition functions may further increase left-turn risk. We examined this problem in a simulated environment that included left-turn scenarios to study the driving behaviors of 28 drivers, ages 37 to 88 years, six of whom had “Useful Field of View” (UFOV) impairments. Subjects also completed a battery of neuropsychological tests. The simulated drive included an urban section with six left turns in three types of scenarios: 1) a semi truck blocking the view of oncoming traffic, 2) a lead vehicle obstruction, and 3) a pedestrian crossing ahead of the turning driver. Results showed a mean (SD) of 1.46 (1.60) collisions per driver (range 0 to 7), 83% of which occurred at intersections with semi trucks. Far visual acuity, contrast sensitivity, UFOV, Mini Mental State Examination, TrailMaking Test Part B, the Wisconsin Card Sort task, and age were all associated with the total number of collisions (Pearson correlation magnitudes between 0.37 to 0.77; p-values<0.05). Spearman correlations were less significant. Findings indicate that visual obstruction by on oncoming semi-truck is a particularly dangerous left-turn situation