99 research outputs found

    Driver monitoring based on low-cost 3-D sensors

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    A solution for driver monitoring and event detection based on 3-D information from a range camera is presented. The system combines 2-D and 3-D techniques to provide head pose estimation and regions-of-interest identification. Based on the captured cloud of 3-D points from the sensor and analyzing the 2-D projection, the points corresponding to the head are determined and extracted for further analysis. Later, head pose estimation with three degrees of freedom (Euler angles) is estimated based on the iterative closest points algorithm. Finally, relevant regions of the face are identified and used for further analysis, e.g., event detection and behavior analysis. The resulting application is a 3-D driver monitoring system based on low-cost sensors. It represents an interesting tool for human factor research studies, allowing automatic study of specific factors and the detection of special event related to the driver, e.g., driver drowsiness, inattention, or head pose.This work was supported by the Spanish Government through the CICYT projects under Grants TRA2010- 20225-C03-01 and TRA 2011-29454-C03-02. The Associate Editor for this paper was C. Olaverri-Monreal

    Data fusion for driver behaviour analysis

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    A driver behaviour analysis tool is presented. The proposal offers a novel contribution based on low-cost hardware and advanced software capabilities based on data fusion. The device takes advantage of the information provided by the in-vehicle sensors using Controller Area Network Bus (CAN-BUS), an Inertial Measurement Unit (IMU) and a GPS. By fusing this information, the system can infer the behaviour of the driver, providing aggressive behaviour detection. By means of accurate GPS-based localization, the system is able to add context information, such as digital map information, speed limits, etc. Several parameters and signals are taken into account, both in the temporal and frequency domains, to provide real time behaviour detection. The system was tested in urban, interurban and highways scenarios.This work was supported by the Spanish Government through the CICYT project (TRA2013-48314-C3-1-R) and DGT project (SPID2015-01802) and by the company SERCORE Tech. S.L. through the project: “Proyecto de Viabilidad de la Comunicación entre el BUS CAN de un Vehículo Específico con un Dispositivo de Adquisición de Datos Móviles”. SERCORE provided invaluable support in the development of the communication technologies through the CAN BUS, presented in this paper

    Pattern Recognition

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    Pattern recognition is a very wide research field. It involves factors as diverse as sensors, feature extraction, pattern classification, decision fusion, applications and others. The signals processed are commonly one, two or three dimensional, the processing is done in real- time or takes hours and days, some systems look for one narrow object class, others search huge databases for entries with at least a small amount of similarity. No single person can claim expertise across the whole field, which develops rapidly, updates its paradigms and comprehends several philosophical approaches. This book reflects this diversity by presenting a selection of recent developments within the area of pattern recognition and related fields. It covers theoretical advances in classification and feature extraction as well as application-oriented works. Authors of these 25 works present and advocate recent achievements of their research related to the field of pattern recognition

    AN INVESTIGATION OF MOTOR VEHICLE DRIVER INATTENTION AND ITS EFFECTS AT HIGHWAY-RAIL GRADE CROSSINGS

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    The relationship between accident injury severity and drivers’ inattentive behavior requires an in-depth investigation – this is especially needed in the case of motor vehicle drivers at highway-rail grade crossings (HRGCs). The relationship between drivers’ personality/ socioeconomic characteristics and inattentive behavior at HRGCs is another topic requiring research. Past educational programs about safe driving at HRGCs have often not been designed to target people who may be in urgent need of such information, which may limit the effectiveness of those programs. This dissertation thus focuses on the following four objectives: to investigate the association between motor vehicle inattentive driving and the severity of drivers’ injuries sustained in crashes reported at or near HRGCs; to investigate the association between drivers’ self-reported inattentive driving experience and a series of factors such as drivers’ knowledge of safe driving, attitudes towards safe driving, etc.; to identify driver groups that have lower or higher levels of knowledge of correct rail crossing negotiation; and to investigate the direct and indirect effects between drivers’ characteristics and their knowledge level as well as their involvement with inattentive driving behavior at HRGCs. The research obtained 12 years of police-reported crash data from the Nebraska Department of Roads and collected data in a statewide random-sample mail questionnaire survey. Statistical analysis methods, including random parameters binary logit model, confirmatory factor analysis, robust linear regression, multinomial logit model, and structural equation models were utilized in this research. Conclusions are that inattentive driving plays a significant role in contributing to more severe injuries in accidents reported in proximity of HRGCs in Nebraska; Nebraska motor vehicle drivers’ personality traits, knowledge levels of negotiating HRGCs and driving experience are associated with inattentive driving; drivers with lower levels of knowledge of correct HRGC negotiation are: drivers who drive vehicles other than passenger cars, have received less safety information, have a shorter driving history, are older, have lower household income, and have higher intent to violate rules at rail crossings; inattentive driving behavior at HRGCs is directly and indirectly affected by their personality traits while drivers’ knowledge of correct HRGC negotiation appears to only have an indirect effect. Advisor: Aemal J.Khatta

    An enactive approach to perceptual augmentation in mobility

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    Event predictions are an important constituent of situation awareness, which is a key objective for many applications in human-machine interaction, in particular in driver assistance. This work focuses on facilitating event predictions in dynamic environments. Its primary contributions are 1) the theoretical development of an approach for enabling people to expand their sampling and understanding of spatiotemporal information, 2) the introduction of exemplary systems that are guided by this approach, 3) the empirical investigation of effects functional prototypes of these systems have on human behavior and safety in a range of simulated road traffic scenarios, and 4) a connection of the investigated approach to work on cooperative human-machine systems. More specific contents of this work are summarized as follows: The first part introduces several challenges for the formation of situation awareness as a requirement for safe traffic participation. It reviews existing work on these challenges in the domain of driver assistance, resulting in an identification of the need to better inform drivers about dynamically changing aspects of a scene, including event probabilities, spatial and temporal distances, as well as a suggestion to expand the scope of assistance systems to start informing drivers about relevant scene elements at an early stage. Novel forms of assistance can be guided by different fundamental approaches that target either replacement, distribution, or augmentation of driver competencies. A subsequent differentiation of these approaches concludes that an augmentation-guided paradigm, characterized by an integration of machine capabilities into human feedback loops, can be advantageous for tasks that rely on active user engagement, the preservation of awareness and competence, and the minimization of complexity in human- machine interaction. Consequently, findings and theories about human sensorimotor processes are connected to develop an enactive approach that is consistent with an augmentation perspective on human-machine interaction. The approach is characterized by enabling drivers to exercise new sensorimotor processes through which safety-relevant spatiotemporal information may be sampled. In the second part of this work, a concept and functional prototype for augmenting the perception of traffic dynamics is introduced as a first example for applying principles of this enactive approach. As a loose expression of functional biomimicry, the prototype utilizes a tactile inter- face that communicates temporal distances to potential hazards continuously through stimulus intensity. In a driving simulator study, participants quickly gained an intuitive understanding of the assistance without instructions and demonstrated higher driving safety in safety-critical highway scenarios. But this study also raised new questions such as whether benefits are due to a continuous time-intensity encoding and whether utility generalizes to intersection scenarios or highway driving with low criticality events. Effects of an expanded assistance prototype with lane-independent risk assessment and an option for binary signaling were thus investigated in a separate driving simulator study. Subjective responses confirmed quick signal understanding and a perception of spatial and temporal stimulus characteristics. Surprisingly, even for a binary assistance variant with a constant intensity level, participants reported perceiving a danger-dependent variation in stimulus intensity. They further felt supported by the system in the driving task, especially in difficult situations. But in contrast to the first study, this support was not expressed by changes in driving safety, suggesting that perceptual demands of the low criticality scenarios could be satisfied by existing driver capabilities. But what happens if such basic capabilities are impaired, e.g., due to poor visibility conditions or other situations that introduce perceptual uncertainty? In a third driving simulator study, the driver assistance was employed specifically in such ambiguous situations and produced substantial safety advantages over unassisted driving. Additionally, an assistance variant that adds an encoding of spatial uncertainty was investigated in these scenarios. Participants had no difficulties to understand and utilize this added signal dimension to improve safety. Despite being inherently less informative than spatially precise signals, users rated uncertainty-encoding signals as equally useful and satisfying. This appreciation for transparency of variable assistance reliability is a promising indicator for the feasibility of an adaptive trust calibration in human-machine interaction and marks one step towards a closer integration of driver and vehicle capabilities. A complementary step on the driver side would be to increase transparency about the driver’s mental states and thus allow for mutual adaptation. The final part of this work discusses how such prerequisites of cooperation may be achieved by monitoring mental state correlates observable in human behavior, especially in eye movements. Furthermore, the outlook for an addition of cooperative features also raises new questions about the bounds of identity as well as practical consequences of human-machine systems in which co-adapting agents may exercise sensorimotor processes through one another.Die Vorhersage von Ereignissen ist ein Bestandteil des Situationsbewusstseins, dessen UnterstĂŒtzung ein wesentliches Ziel diverser Anwendungen im Bereich Mensch-Maschine Interaktion ist, insbesondere in der Fahrerassistenz. Diese Arbeit zeigt Möglichkeiten auf, Menschen bei Vorhersagen in dynamischen Situationen im Straßenverkehr zu unterstĂŒtzen. Zentrale BeitrĂ€ge der Arbeit sind 1) eine theoretische Auseinandersetzung mit der Aufgabe, die menschliche Wahrnehmung und das VerstĂ€ndnis von raum-zeitlichen Informationen im Straßenverkehr zu erweitern, 2) die EinfĂŒhrung beispielhafter Systeme, die aus dieser Betrachtung hervorgehen, 3) die empirische Untersuchung der Auswirkungen dieser Systeme auf das Nutzerverhalten und die Fahrsicherheit in simulierten Verkehrssituationen und 4) die VerknĂŒpfung der untersuchten AnsĂ€tze mit Arbeiten an kooperativen Mensch-Maschine Systemen. Die Arbeit ist in drei Teile gegliedert: Der erste Teil stellt einige Herausforderungen bei der Bildung von Situationsbewusstsein vor, welches fĂŒr die sichere Teilnahme am Straßenverkehr notwendig ist. Aus einem Vergleich dieses Überblicks mit frĂŒheren Arbeiten zeigt sich, dass eine Notwendigkeit besteht, Fahrer besser ĂŒber dynamische Aspekte von Fahrsituationen zu informieren. Dies umfasst unter anderem Ereigniswahrscheinlichkeiten, rĂ€umliche und zeitliche Distanzen, sowie eine frĂŒhere Signalisierung relevanter Elemente in der Umgebung. Neue Formen der Assistenz können sich an verschiedenen grundlegenden AnsĂ€tzen der Mensch-Maschine Interaktion orientieren, die entweder auf einen Ersatz, eine Verteilung oder eine Erweiterung von Fahrerkompetenzen abzielen. Die Differenzierung dieser AnsĂ€tze legt den Schluss nahe, dass ein von Kompetenzerweiterung geleiteter Ansatz fĂŒr die BewĂ€ltigung jener Aufgaben von Vorteil ist, bei denen aktiver Nutzereinsatz, die Erhaltung bestehender Kompetenzen und Situationsbewusstsein gefordert sind. Im Anschluss werden Erkenntnisse und Theorien ĂŒber menschliche sensomotorische Prozesse verknĂŒpft, um einen enaktiven Ansatz der Mensch-Maschine Interaktion zu entwickeln, der einer erweiterungsgeleiteten Perspektive Rechnung trĂ€gt. Dieser Ansatz soll es Fahrern ermöglichen, sicherheitsrelevante raum-zeitliche Informationen ĂŒber neue sensomotorische Prozesse zu erfassen. Im zweiten Teil der Arbeit wird ein Konzept und funktioneller Prototyp zur Erweiterung der Wahrnehmung von Verkehrsdynamik als ein erstes Beispiel zur Anwendung der Prinzipien dieses enaktiven Ansatzes vorgestellt. Dieser Prototyp nutzt vibrotaktile Aktuatoren zur Kommunikation von Richtungen und zeitlichen Distanzen zu möglichen Gefahrenquellen ĂŒber die Aktuatorposition und -intensitĂ€t. Teilnehmer einer Fahrsimulationsstudie waren in der Lage, in kurzer Zeit ein intuitives VerstĂ€ndnis dieser Assistenz zu entwickeln, ohne vorher ĂŒber die FunktionalitĂ€t unterrichtet worden zu sein. Sie zeigten zudem ein erhöhtes Maß an Fahrsicherheit in kritischen Verkehrssituationen. Doch diese Studie wirft auch neue Fragen auf, beispielsweise, ob der Sicherheitsgewinn auf kontinuierliche Distanzkodierung zurĂŒckzufĂŒhren ist und ob ein Nutzen auch in weiteren Szenarien vorliegen wĂŒrde, etwa bei Kreuzungen und weniger kritischem longitudinalen Verkehr. Um diesen Fragen nachzugehen, wurden Effekte eines erweiterten Prototypen mit spurunabhĂ€ngiger KollisionsprĂ€diktion, sowie einer Option zur binĂ€ren Kommunikation möglicher Kollisionsrichtungen in einer weiteren Fahrsimulatorstudie untersucht. Auch in dieser Studie bestĂ€tigen die subjektiven Bewertungen ein schnelles VerstĂ€ndnis der Signale und eine Wahrnehmung rĂ€umlicher und zeitlicher Signalkomponenten. Überraschenderweise berichteten Teilnehmer grĂ¶ĂŸtenteils auch nach der Nutzung einer binĂ€ren Assistenzvariante, dass sie eine gefahrabhĂ€ngige Variation in der IntensitĂ€t von taktilen Stimuli wahrgenommen hĂ€tten. Die Teilnehmer fĂŒhlten sich mit beiden Varianten in der Fahraufgabe unterstĂŒtzt, besonders in Situationen, die von ihnen als kritisch eingeschĂ€tzt wurden. Im Gegensatz zur ersten Studie hat sich diese gefĂŒhlte UnterstĂŒtzung nur geringfĂŒgig in einer messbaren SicherheitsverĂ€nderung widergespiegelt. Dieses Ergebnis deutet darauf hin, dass die Wahrnehmungsanforderungen der Szenarien mit geringer KritikalitĂ€t mit den vorhandenen FahrerkapazitĂ€ten erfĂŒllt werden konnten. Doch was passiert, wenn diese FĂ€higkeiten eingeschrĂ€nkt werden, beispielsweise durch schlechte Sichtbedingungen oder Situationen mit erhöhter AmbiguitĂ€t? In einer dritten Fahrsimulatorstudie wurde das Assistenzsystem in speziell solchen Situationen eingesetzt, was zu substantiellen Sicherheitsvorteilen gegenĂŒber unassistiertem Fahren gefĂŒhrt hat. ZusĂ€tzlich zu der vorher eingefĂŒhrten Form wurde eine neue Variante des Prototyps untersucht, welche rĂ€umliche Unsicherheiten der Fahrzeugwahrnehmung in taktilen Signalen kodiert. Studienteilnehmer hatten keine Schwierigkeiten, diese zusĂ€tzliche Signaldimension zu verstehen und die Information zur Verbesserung der Fahrsicherheit zu nutzen. Obwohl sie inherent weniger informativ sind als rĂ€umlich prĂ€zise Signale, bewerteten die Teilnehmer die Signale, die die Unsicherheit ĂŒbermitteln, als ebenso nĂŒtzlich und zufriedenstellend. Solch eine WertschĂ€tzung fĂŒr die Transparenz variabler InformationsreliabilitĂ€t ist ein vielversprechendes Indiz fĂŒr die Möglichkeit einer adaptiven Vertrauenskalibrierung in der Mensch-Maschine Interaktion. Dies ist ein Schritt hin zur einer engeren Integration der FĂ€higkeiten von Fahrer und Fahrzeug. Ein komplementĂ€rer Schritt wĂ€re eine Erweiterung der Transparenz mentaler ZustĂ€nde des Fahrers, wodurch eine wechselseitige Anpassung von Mensch und Maschine möglich wĂ€re. Der letzte Teil dieser Arbeit diskutiert, wie diese Transparenz und weitere Voraussetzungen von Mensch-Maschine Kooperation erfĂŒllt werden könnten, indem etwa Korrelate mentaler ZustĂ€nde, insbesondere ĂŒber das Blickverhalten, ĂŒberwacht werden. Des Weiteren ergeben sich mit Blick auf zusĂ€tzliche kooperative FĂ€higkeiten neue Fragen ĂŒber die Definition von IdentitĂ€t, sowie ĂŒber die praktischen Konsequenzen von Mensch-Maschine Systemen, in denen ko-adaptive Agenten sensomotorische Prozesse vermittels einander ausĂŒben können

    Pharmacodynamics and pharmacokinetics of centrally acting depressants in man

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    Spatial Analysis of Teen Driver-Related Crashes in Kansas

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    In the United States, the risk of vehicle crashes is higher among teens than among any other age group. Accordingly, in Kansas, teen drivers ages 14 to 19 were one of the primary foci of Kansas Department of Transportation’s (KDOT’s) Strategic Highway Safety Plan (SHSP) to reduce the number of traffic injuries and fatalities. However, after several years of improving metrics, it appears that overall teen crashes have begun to increase in the past few years and the SHSP goals were not met. Most previous studies investigated the effects of demographic differences and nonspatial factors associated with crashes such as gender, age, driving under the influence of drugs or alcohol, the presence of passengers, and distractions. Besides these factors, it was necessary to investigate and understand how teen-related crashes are correlated and patterned spatially. However, adopting the spatial analysis methodology to identify the hotspots for teen drivers and factors behind their crashes has been underutilized. This research was conducted to develop a methodology to identify statistically significant spatial patterns for crashes involving teen drivers. Also, modelling was performed that identified spatial relationships between teen-related crashes and contributed factors that significantly influence the number of these crashes using an ordinary linear regression (OLS) model and geographically weighted regression (GWR). The utilized data were extracted from the KDOT crash database and other resources such as the Fatality Analysis Reporting System (FARS), the US Census Bureau, and the Kansas Department of Education. The analyzed crashes included crashes involving teen drivers aged between 14 and 19. The spatial analysis and modeling were conducted at the state level and Unified School District (USD) level using ArcGIS Pro software (Version 2.3.2). The spatial analysis tools were used to find statistically significant hotspots and outliers for fatal and non-fatal crashes at the state level, and fatal and severe injuries at the USD level. Most of the statistically significant hotspots and outliers were centered in the most populated counties such as Johnson, Sedgwick, and Wyandotte County. From 18 candidate exploratory variables, two exploratory variables were statistically significant to build a predictive model using OLS and GWR. The two exploratory variables were the miles of non-state roads and the number of passenger cars in counties. The predictive model showed that the number of crashes involving teen driver was expected to be lower by more than three percent by 2026. The methodology followed in this research was found to be applicable and valuable to spatially analyze teen-related crashes at the state and USD levels. The method was useful for analyzing a subset of crashes involving teen drivers; it can also be used to analyze other subgroups such as alcohol-related crashes, older driver crashes, or commercial vehicle crashes. The model represents useful guidance for the related parties’ allocation of limited resource for reducing crashes, and is helpful in predicting future crashes based on historical trends

    The Crewman's Associate for Path Control (CAPC): an automated driving function

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    Army Tank Automotive Command, Warren, Mich.http://deepblue.lib.umich.edu/bitstream/2027.42/1134/2/88210.0001.001.pd

    Monotony: the effect of task demand on subjective experience and performance

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    Although monotony is widely recognised as being detrimental to performance, its occurrence and effects are not yet well understood. This is despite the fact that task-related characteristics, such as monotony and low task demand, have been shown to contribute to performance decrements over time. Three empirical studies were conducted in this research to further our understanding of the factors that contribute to the experience of monotony and the role task demand may play in mitigating monotony-related effects on performance. The first study was lab-based to determine the effect of task demand on the subjective experience and performance of a computer-based monotonous task. Forty participants performed a monotonous task characterised by either low cognitive demand or high cognitive demand, as well as a number of self-report scales. Results clearly demonstrated that despite a similar subjective experience across both tasks, there were clear benefits for performance of the high demand monotonous task. Study two was designed to determine if monotony and fatigue are indeed issues for the potentially ‘at risk’ population of train drivers and if so, are there defining factors that contribute to these experiences. Survey results indicate that train drivers, particularly passenger drivers, experience monotony and fatigue on a regular basis while driving trains for work and the majority believe that these experiences adversely impact on their train management skills. Results also showed that train drivers are able to distinguish between the experiences of monotony and of fatigue and many utilise a somewhat limited range of strategies to cope with these experiences. Study three combined what was learned from the first two studies to determine if increasing the cognitive demand of a monotonous train driving task could mitigate the monotony-related effects on performance. The results clearly show that even a relatively minor increase in cognitive demand can mitigate adverse monotony-related effects on performance for extended periods of time, in this case over two hours of driving in a highly monotonous simulated scenario. Monotony is an inherent characteristic of transport industries, including rail, aviation and road transport, which can have adverse impact on safety, reliability and efficiency. These studies highlight possible strategies for mitigating these adverse effects
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