6,065 research outputs found

    A New Vehicle Localization Scheme Based on Combined Optical Camera Communication and Photogrammetry

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    The demand for autonomous vehicles is increasing gradually owing to their enormous potential benefits. However, several challenges, such as vehicle localization, are involved in the development of autonomous vehicles. A simple and secure algorithm for vehicle positioning is proposed herein without massively modifying the existing transportation infrastructure. For vehicle localization, vehicles on the road are classified into two categories: host vehicles (HVs) are the ones used to estimate other vehicles' positions and forwarding vehicles (FVs) are the ones that move in front of the HVs. The FV transmits modulated data from the tail (or back) light, and the camera of the HV receives that signal using optical camera communication (OCC). In addition, the streetlight (SL) data are considered to ensure the position accuracy of the HV. Determining the HV position minimizes the relative position variation between the HV and FV. Using photogrammetry, the distance between FV or SL and the camera of the HV is calculated by measuring the occupied image area on the image sensor. Comparing the change in distance between HV and SLs with the change in distance between HV and FV, the positions of FVs are determined. The performance of the proposed technique is analyzed, and the results indicate a significant improvement in performance. The experimental distance measurement validated the feasibility of the proposed scheme

    Static and Motion-Based Visual Features Used by Airport Tower Controllers: Some Implications for the Design of Remote or Virtual Towers

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    Visual motion and other visual cues are used by tower controllers to provide important support for their control tasks at and near airports. These cues are particularly important for anticipated separation. Some of them, which we call visual features, have been identified from structured interviews and discussions with 24 active air traffic controllers or supervisors. The visual information that these features provide has been analyzed with respect to possible ways it could be presented at a remote tower that does not allow a direct view of the airport. Two types of remote towers are possible. One could be based on a plan-view, map-like computer-generated display of the airport and its immediate surroundings. An alternative would present a composite perspective view of the airport and its surroundings, possibly provided by an array of radially mounted cameras positioned at the airport in lieu of a tower. An initial more detailed analyses of one of the specific landing cues identified by the controllers, landing deceleration, is provided as a basis for evaluating how controllers might detect and use it. Understanding other such cues will help identify the information that may be degraded or lost in a remote or virtual tower not located at the airport. Some initial suggestions how some of the lost visual information may be presented in displays are mentioned. Many of the cues considered involve visual motion, though some important static cues are also discussed

    A review of traffic simulation software

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    Computer simulation of tra c is a widely used method in research of tra c modelling, planning and development of tra c networks and systems. Vehicular tra c systems are of growing concern and interest globally and modelling arbitrarily complex tra c systems is a hard problem. In this article we review some of the tra c simulation software applications, their features and characteristics as well as the issues these applications face. Additionally, we introduce some algorithmic ideas, underpinning data structural approaches and quanti able metrics that can be applied to simulated model systems

    Intelligent tutoring in virtual reality for highly dynamic pedestrian safety training

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    This thesis presents the design, implementation, and evaluation of an Intelligent Tutoring System (ITS) with a Virtual Reality (VR) interface for child pedestrian safety training. This system enables children to train practical skills in a safe and realistic virtual environment without the time and space dependencies of traditional roadside training. This system also employs Domain and Student Modelling techniques to analyze user data during training automatically and to provide appropriate instructions and feedback. Thus, the traditional requirement of constant monitoring from teaching personnel is greatly reduced. Compared to previous work, especially the second aspect is a principal novelty for this domain. To achieve this, a novel Domain and Student Modeling method was developed in addition to a modular and extensible virtual environment for the target domain. While the Domain and Student Modeling framework is designed to handle the highly dynamic nature of training in traffic and the ill-defined characteristics of pedestrian tasks, the modular virtual environment supports different interaction methods and a simple and efficient way to create and adapt exercises. The thesis is complemented by two user studies with elementary school children. These studies testify great overall user acceptance and the system’s potential for improving key pedestrian skills through autonomous learning. Last but not least, the thesis presents experiments with different forms of VR input and provides directions for future work.Diese Arbeit behandelt den Entwurf, die Implementierung sowie die Evaluierung eines intelligenten Tutorensystems (ITS) mit einer Virtual Reality (VR) basierten Benutzeroberfläche zum Zwecke von Verkehrssicherheitstraining für Kinder. Dieses System ermöglicht es Kindern praktische Fähigkeiten in einer sicheren und realistischen Umgebung zu trainieren, ohne den örtlichen und zeitlichen Abhängigkeiten des traditionellen, straßenseitigen Trainings unterworfen zu sein. Dieses System macht außerdem von Domain und Student Modelling Techniken gebrauch, um Nutzerdaten während des Trainings zu analysieren und daraufhin automatisiert geeignete Instruktionen und Rückmeldung zu generieren. Dadurch kann die bisher erforderliche, ständige Überwachung durch Lehrpersonal drastisch reduziert werden. Verglichen mit bisherigen Lösungen ist insbesondere der zweite Aspekt eine grundlegende Neuheit für diesen Bereich. Um dies zu erreichen wurde ein neuartiges Framework für Domain und Student Modelling entwickelt, sowie eine modulare und erweiterbare virtuelle Umgebung für diese Art von Training. Während das Domain und Student Modelling Framework so entworfen wurde, um mit der hohen Dynamik des Straßenverkehrs sowie den vage definierten Fußgängeraufgaben zurecht zu kommen, unterstützt die modulare Umgebung unterschiedliche Eingabeformen sowie eine unkomplizierte und effiziente Methode, um Übungen zu erstellen und anzupassen. Die Arbeit beinhaltet außerdem zwei Nutzerstudien mit Grundschulkindern. Diese Studien belegen dem System eine hohe Benutzerakzeptanz und stellt das Potenzial des Systems heraus, wichtige Fähigkeiten für Fußgängersicherheit durch autodidaktisches Training zu verbessern. Nicht zuletzt beschreibt die Arbeit Experimente mit verschiedenen Formen von VR Eingaben und zeigt die Richtung für zukünftige Arbeit auf

    Take It to the Curb: Scalable Communication Between Autonomous Cars and Vulnerable Road Users Through Curbstone Displays

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    Automated driving will require new approaches to the communication between vehicles and vulnerable road users (VRUs) such as pedestrians, e.g., through external human-machine interfaces (eHMIs). However, the majority of eHMI concepts are neither scalable (i.e., take into account complex traffic scenarios with multiple vehicles and VRUs), nor do they optimize traffic flow. Speculating on the upgrade of traffic infrastructure in the automated city, we propose Smart Curbs, a scalable communication concept integrated into the curbstone. Using a combination of immersive and non-immersive prototypes, we evaluated the suitability of our concept for complex urban environments in a user study (N = 18). Comparing the approach to a projection-based eHMI, our findings reveal that Smart Curbs are safer to use, as our participants spent less time on the road when crossing. Based on our findings, we discuss the potential of Smart Curbs to mitigate the scalability problem in AV-pedestrian communication and simultaneously enhance traffic flow

    Design and evaluation of safety-critical applications based on inter-vehicle communication

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    Inter-vehicle communication has a potential to improve road traffic safety and efficiency. Technical feasibility of communication between vehicles has been extensively studied, but due to the scarcity of application-level research, communication\u27s impact on the road traffic is still unclear. This thesis addresses this uncertainty by designing and evaluating two fail-safe applications, namely, Rear-End Collision Avoidance and Virtual Traffic Lights
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