Altering driver's goals and motives for at-risk driving is likely to reduce the frequency of at-risk driving behaviors and their associated crashes and injuries. However, most driving occurs when people are alone with little supervisions or accountability. Thus, a self-management for safety (SMS) intervention may be the most appropriate technique to decrease at-risk driving behaviors. The current research evaluated an SMS process with college students on a simulated driving task. Participants included 93 university students (41 males, 52 females) randomly assigned to one of three groups (31 participants per group). Participants in the Control group did not receive any of the intervention materials; they were instructed to drive as they normally drive on each trial. Participants in the Self-Monitoring + Objective Feedback group received objective feedback from the experimenter about their actual performance on the target driving behavior as well as personal feedback from their self-monitoring forms. These participants recorded their individual improvement goals on the targeted driving behavior. Participants in the Self-Monitoring group recorded their individual improvement goals on the targeted driving behavior, but received only personal feedback from their self-monitoring forms. Similar to past self-management interventions directed at increasing safety-related driving behavior (Hickman & Geller, in press; Krause, 1997; Olson & Austin, 2001), SMS led to clear improvement in subsequent safety performance. Based on the recorded driving behaviors of 93 participants, SMS was effective in increasing the mean percentage of total driving time traveling below the posted speed limit compared to a Control group that did not receive any of the SMS components. Across the four trials, participants in the SM and SM + OFB group significantly increased the percentage of total driving time traveling below the posted speed limit by 13.4 (18.3%) and 14.5 (19.8%) percentage points, respectively, compared to participants in the Control group. / Ph. D.

This research effort aims to create a new car-following model that accounts for the effects of emotion on driver behavior. This research effort is divided into eight research milestones: (1) the development of a segmentation and clustering algorithm to perform new investigations into driver behavior; (2) the finding that driver behavior is different between drivers, between car-following periods, and within a car-following period; (3) the finding that there are patterns in the distribution of driving behaviors; (4) the finding that driving states can result in different driving actions and that the same driving action can be the result of multiple driving states; (5) the finding that the performance of car-following models can be improved by calibration to state-action clusters; (6) the development of a psychophysiological driving simulator study; (7) the finding that the distribution of driving behavior is affected by emotional states; and (8) the development of a car-following model that incorporates the influence of emotions. / Ph. D.

L'objectif de cette thèse est de déterminer l'impact de la distraction du conducteur et de la consommation d'alcool, ainsi que leurs interactions, sur les performances des conducteurs novices. Des mesures subjectives des comportements à risques et des performances objectives sur simulateur de conduite sont recueillies. Une première expérience étudie les déterminants psycho-sociaux de la prise de risque et le type de comportements à risques rapportés par les jeunes conducteurs. La seconde expérience s'intéresse aux performances lors d'une tâche d'attention divisée sur simulateur de conduite en fonction de l'expérience, de l'âge et du type d'apprentissage suivi. Enfin, la troisième expérimentation a pour objectif d'étudier l'impact de faible et forte dose d'alcool sur les performances de jeunes conducteurs, novices et expérimentés, lors d'une tâche d'attention divisée. Ces recherches permettent d'approfondir nos connaissances sur les mécanismes d'actions de la distraction et de l'alcool sur les performances du conducteur, en particulier des novices. / The aim of this thesis is to investigate the effects of driver distraction by a secondary task, alcohol consumption and their interaction on performance depending on driving experience. Objective and subjective measures are recorded. The first experience studies the determinants of risk-taking and the kind of risky driving behaviour recalled by young drivers. Differences depending on driving experience, sex, and initial training show an increment of driving risk-taking for young drivers with 3 years of driving experience and with traditional training. The aim of the second experiment is to study the effects of a divided attention task on performance depending on driving experience, age and initial training. Novice drivers have more difficulties to divide their attention between two tasks than experienced drivers, notably when one of these tasks is complex or located in peripheral vision. The third experiment studies the negative impact of alcohol (low and high doses) on young drivers' performances, novice and experienced, during a divided attention task. The classical detriment effect of alcohol on driving performance is replicated, and this effect is more pronounced for novice drivers who adopt a risky driving behaviour under the influence of alcohol, even with a low dose of alcohol. This research improves our fundamental knowledge on how distraction and alcohol impair drivers' performance, notably when they are novice.

Cette thèse présente le produit d'un projet de recherche doctoral ambitieux qui a procédé à la réalisation des premières étapes cruciales de conception, développement et évaluation d'un test de mesure de l'impact de la distraction du conducteur (DDIAT). L'objectif de ce test est de mesurer l'impact que la distraction du conducteur a sur les performances de conduite et les comportements du conducteur. En outre, une présentation sera effectuée des étapes majeures qui restent encore à réaliser, et qui dépassent le cadre de cette thèse, pour entièrement valider et implémenter le test. Le DDIAT est composé de trois épreuves de conduite ou Drives (Drive 1, 2 et 3), qui ont été conçues à partir des principes de la littérature de la cognition et de l’attention. Les épreuves Drive 1 et Drive 2 ont été implémentées dans un environnement de conduite urbain et elles incluent des conditions de feux de circulation qui ont été conçues pour ressembler aux feux de circulation rencontrés dans des conditions de conduite réelles. De plus, l'épreuve Drive 1 inclut des scénarios de traversée d’une file de véhicules pour tourner à gauche à une intersection (gap acceptance), dans lesquels les participants doivent prendre la décision cruciale de sélectionner un intervalle entre deux véhicules pour traverser. L'épreuve Drive 2 inclut plusieurs instances de suivi de véhicule, dont certaines où le véhicule suivi freine brutalement et où le participant doit réagir de manière appropriée pour éviter une collision frontale. Enfin, l'épreuve Drive 3 a été conçue pour implicitement mesurer la conscience de la situation dans un environnement de conduite autoroutier, mais cette épreuve n'a pas été entièrement implémentée dans le cadre de cette thèse. Les épreuves Drive 1 et Drive 2 ont été évaluées dans une expérimentation sur un simulateur de conduite avancé. Les résultats de cette évaluation expérimentale ont montré que les deux épreuves Drive 1 et Drive 2 étaient capables de : a) représenter la conduite réelle (c.-à-d., elles vérifient la validité de contenu et la validité apparente), b) mesurer l'impact de la distraction du conducteur et c) de faire la distinction entre les deux tâches secondaires (l'une visuelle/manuelle, l'autre auditive/cognitive) à travers leur impact sur les performances de conduite. En conclusion, le travail complété dans le cadre de cette thèse constitue les premières étapes cruciales nécessaires au développement d'un DDIAT complet qui surpasse les limitations des outils et tests précédents et fournit également les bases d'une méthode standardisée pour aider à surpasser les incohérences qui existent entre les différentes études de mesure de l'impact de la distraction du conducteur. / This thesis describes the outcomes of an ambitious doctoral research program that carried out the initial critical steps in the design, development, and evaluation of a driver distraction impact assessment test (DDIAT). The purpose of this test has been to assess the impact driver distraction has on driving performance and driver behaviour. The thesis also describes the critical steps, beyond the scope of this thesis, that remain to be carried out in order to fully validate and implement the complete DDIAT proposed in this thesis. As part of the DDIAT proposed in this thesis, three Drives (Drive 1, 2, and 3) were designed and created from basic attention principles and by using a complex experimental design. Drive 1 and Drive 2 were implemented in an urban driving environment and included traffic light conditions that were designed to resemble real world traffic light conditions. Furthermore, Drive 1 included gap acceptance events in which participants had to make a crucial and important decision when selecting a gap to turn left though an oncoming stream of vehicles. Drive 2 included various car following instances and lead vehicle braking events, whereby participants had to react suddenly to avoid a frontal collision. Lastly, Drive 3 was designed to implicitly measure situation awareness on a highway driving environment – but was outside of the scope of the thesis to investigate. Drive 1 and Drive 2 were evaluated in an experiment implemented in an advanced driving simulator. The results from this evaluation experiment showed that both Drive 1 and Drive 2: a) represent real world driving (i.e., have content and face validity); b) are capable of measuring the impact of driver distraction; and c) are capable of distinguishing between the impact on driving of two secondary tasks (one visual/manual, the other auditory/cognitive). In conclusion, the work completed as part of this thesis provided a first and important step towards the development of a complete DDIAT that overcomes the shortcomings of previous tests and tools and also provides the beginnings of a standardised method to assist in overcoming the inconsistencies that exist across studies in the measurement of driver distraction.

Os simuladores de direção são ferramentas de pesquisa que permitem estudar o comportamento do condutor em diversos cenários de direção, de forma rápida, segura e econômica. Este estudo faz parte de um projeto de pesquisa que visa utilizar essas ferramentas na avaliação de projetos de sinalização, antes da sua implantação na rodovia. Em particular, o objetivo deste trabalho foi analisar como os condutores percebem a sinalização vertical dentro de um ambiente simulado de direção, apoiado no uso de um sistema de rastreio do olhar. O andamento da pesquisa abrangeu a montagem do simulador e do sistema de rastreio do olhar, a geração do ambiente simulado de direção, o experimento no simulador para medir a percepção da sinalização dentro do ambiente virtual, e por último, a análise e validação dos resultados. No experimento, 21 condutores dirigiram em um trecho de 10 quilômetros da rodovia BR-116 que possui 31 sinais de trânsito, para mensurar a distância de percepção, o número de fixações e o tempo de observação da sinalização, assim como a variação da velocidade após percepção da mesma. A percepção da sinalização dentro do ambiente virtual foi semelhante à reportada na literatura para estudos em estradas: em média, os condutores perceberam um de cada três sinais, o tempo de observação foi de 360 milissegundos, a distância de percepção foi de 100 metros e somente a percepção dos limites de velocidade foi relevante no comportamento dos condutores. Adicionalmente, obteve-se uma validade relativa entre as velocidades no simulador e as velocidades de operação medidas no trecho estudado. Nesse sentido, os resultados deste estudo sustentam a viabilidade e a validade do simulador de direção na avaliação de projetos de sinalização. Finalmente, como contribuição adicional, propuseram-se medidas para aprimorar a sinalização no trecho estudado e o realismo do simulador de direção. / Driving simulators are research tools that allow studying driver behavior on several driving scenarios, in a safely and cost-effective way. This study pertains to a research project whose goal is to use these tools in the assessment of road signage projects, before their implementation on roadway. In particular, the goal of this study was to analyze how drivers perceive road signs within a simulated driving environment, supported by an eye tracking system. The research development included the assembling of the driving simulator and the eye tracking system, the generation of the simulated environment, an experiment to measure the signaling perception within that environment, and finally, the analysis and validation of the results. In the experiment, twenty-one drivers drove over a ten-kilometer virtual segment of the BR-116 roadway, that has thirty-one traffic signs, in order to measure the number of eye fixations, the perception distance and the observation time over each sign, as well as, the speed change after its perception. The perception of the road signs within the virtual environment was similar to that reported in the literature for on-road studies: in average, the drivers perceived one-third of the traffic signs, the mean observation time was 360 milliseconds, the mean perception distance was 100 meters and only the speed limit signs perception was relevant on the drivers behavior. Furthermore, it was observed a relative validity between the driving simulator speeds and the actual operating speeds in the studied segment. In that sense, this study shows the feasibility and validity of using driving simulators to assess road signage projects. Finally, some countermeasures were proposed in order to enhance both the road signaling of the studied segment and the road signs perception within the simulated driving environment.

Dangerous driving behaviors are influenced by multiple factors including cognitive processes such as impulse inhibition and attentiveness. Impulsiveness, inattention, and cognitive failures have been linked to other risky behaviors, but a comprehensive evaluation using multiple methods of measurement of these has never been conducted to analyze their impact on dangerous driving. The purpose of this study was to examine influences of attentional abilities, impulsiveness, and cognitive failures on reported and demonstrated dangerous driving behaviors. Seventy-five participants completed a self-report dangerous driving measure, a self-report ADHD measure, a self-report impulsiveness measure, a continuous performance task to measure behavioral impulsivity and inattention, a measure of cognitive failures, and a driving simulator task. Two hierarchical linear regressions with simultaneous entry into blocks were used to analyze contributions of impulsiveness, inattention, and cognitive failures assessments in predicting dangerous driving behavior. Results indicated these assessments accounted for a significant proportion of the variance in Dula Dangerous Driving Index (3DI) scores above and beyond the effects of age and sex, Adjusted R▓ = .20, F(6, 59) = 2.51, p < .05, but no significant individual predictors emerged. Scores on these measures were also found to account for a significant amount of the variance in risky driving as measured by the driving simulator, above and beyond the effects of age and sex, Adjusted R▓ = .15, F(6, 60) = 2.91, p < .05, and identified BIS-11 scores and ADHD-RS impulsiveness scores as significant individual predictors. It seems that despite multiple methods of assessment, it is still difficult to capture the assumed relationships between each of these factors and driving. Though each assessment measures different aspects of constructs related to dangerous driving, the lack of relationships and predictive abilities may indicate that impulsiveness, inattention, cognitive failures, and dangerous driving may be more complex and multifaceted than previously understood.

<p>The objective of this thesis is to implement a basic, yet realistic, ESC system into the VTI simulator environment. This system is then validated to assure that it is working properly and provides a realistic behavior.</p><p>The implemented ESC system is used in a study, where the ESC system could be turned on and off, to evaluate the benefits of an ESC system after a side impact. This study shows that an ESC system may aid the driver in such a critical situation when the driver is unaware that a side impact will occur. With the ESC system active no driver lost control while with the system inactive there were five drivers that lost control, but deviations in initial speed give statistical difficulties, thus more tests are needed. In the case where the driver knows that an impact will occur the ESC system showed to stabilize the automobile faster and it is shown that an expected improvement in stabilization time is between 40 to 62 percent. It was also seen during this part of the scenario that 2 percent loss of control occurred with an active ESC system and 45 percent without.</p>

<p>Driving simulators are used to conduct experiments on for example driver behavior, road design, and vehicle characteristics. The results of the experiments often depend on the traffic conditions. One example is the evaluation of cellular phones and how they affect driving behavior. It is clear that the ability to use phones when driving depends on traffic intensity and composition, and that realistic experiments in driving simulators therefore has to include surrounding traffic.</p><p>This thesis describes a model that generates and simulates surrounding vehicles for a driving simulator. The proposed model generates a traffic stream, corresponding to a given target flow and simulates realistic interactions between vehicles. The model is built on established techniques for time-driven microscopic simulation of traffic and uses an approach of only simulating the closest neighborhood of the driving simulator vehicle. In our model this closest neighborhood is divided into one inner region and two outer regions. Vehicles in the inner region are simulated according to advanced behavioral models while vehicles in the outer regions are updated according to a less time-consuming model. The presented work includes a new framework for generating and simulating vehicles within a moving area. It also includes the development of enhanced models for car-following and overtaking and a simple mesoscopic traffic model.</p><p>The developed model has been integrated and tested within the VTI Driving simulator III. A driving simulator experiment has been performed in order to check if the participants observe the behavior of the simulated vehicles as realistic or not. The results were promising but they also indicated that enhancements could be made. The model has also been validated on the number of vehicles that catches up with the driving simulator vehicle and vice versa. The agreement is good for active and passive catch-ups on rural roads and for passive catch-ups on freeways, but less good for active catch-ups on freeways.</p>

The objective of this thesis is to implement a basic, yet realistic, ESC system into the VTI simulator environment. This system is then validated to assure that it is working properly and provides a realistic behavior. The implemented ESC system is used in a study, where the ESC system could be turned on and off, to evaluate the benefits of an ESC system after a side impact. This study shows that an ESC system may aid the driver in such a critical situation when the driver is unaware that a side impact will occur. With the ESC system active no driver lost control while with the system inactive there were five drivers that lost control, but deviations in initial speed give statistical difficulties, thus more tests are needed. In the case where the driver knows that an impact will occur the ESC system showed to stabilize the automobile faster and it is shown that an expected improvement in stabilization time is between 40 to 62 percent. It was also seen during this part of the scenario that 2 percent loss of control occurred with an active ESC system and 45 percent without.

A critical part of traffic safety is a driver’s ability to detect and respond to emergency roadway hazards. This thesis uses eye movements and motor responses to divide driver perception-response time in three stages: perception, inspection, and movement time. The effects of cognitive distraction and repeated exposure on each stage were investigated for three distinct hazards (left-turning vehicle, pedestrian, right-incursion vehicle). In general, there were varying effects of cognitive distraction observed depending on the hazard being responded to. Cognitive distraction resulted in a significant increase in perception times for the pedestrian and right-incursion vehicle hazards, whereas cognitive distraction resulted in significantly longer inspection times for the left-turning vehicle hazard. When considering the effect of repeated scenario exposure, perception times were the most greatly affected. Perception times were significantly shorter during the second exposure to the left-turning vehicle hazard in the baseline condition, and for all hazards in the distraction condition.