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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Eco-Driving in the Vicinity of Roadway Intersections - Algorithmic Development, Modeling and Testing

Kamalanathsharma, Raj Kishore 06 May 2014 (has links)
Vehicle stops and speed variations account for a large percentage of vehicle fuel losses especially at signalized intersections. Recently, researchers have attempted to develop tools that reduce these losses by capitalizing on traffic signal information received via vehicle connectivity with traffic signal controllers. Existing state-of-the-art approaches, however, only consider surrogate measures (e.g. number of vehicle stops, time spent accelerating and decelerating, and/or acceleration or deceleration levels) in the objective function and fail to explicitly optimize vehicle fuel consumption levels. Furthermore, the majority of these models do not capture vehicle acceleration and deceleration limitations in addition to vehicle-to-vehicle interactions as constraints within the mathematical program. The connectivity between vehicles and infrastructure, as achieved through Connected Vehicles technology, can provide a vehicle with information that was not possible before. For example, information on traffic signal changes, traffic slow-downs and even headway and speed of lead vehicles can be shared. The research proposed in this dissertation uses this information and advanced computational models to develop fuel-efficient vehicle trajectories, which can either be used as guidance for drivers or can be attached to an electronic throttle controlled cruise control system. This fuel-efficient cruise control system is known as an Eco-Cooperative Adaptive Cruise Control (ECACC) system. In addition to the ECACC presented here, the research also expands on some of the key eco-driving concepts such as fuel-optimizing acceleration models, which could be used in conjunction with conventional vehicles and even autonomous vehicles, or assistive systems that are being implemented in vehicles. The dissertation first presents the results from an on-line survey soliciting driver input on public perceptions of in-vehicle assistive devices. The results of the survey indicate that user-acceptance to systems that enhance safety and efficiency is ranked high. Driver–willingness to use advanced in-vehicle technology and cellphone applications is also found to be subjective on what benefits it has to offer and safety and efficiency are found to be in the top list. The dissertation then presents the algorithmic development of an Eco-Cooperative Adaptive Cruise Control system. The modeling of the system constitutes a modified state-of-the-art path-finding algorithm within a dynamic programming framework to find near-optimal and near-real-time solutions to a complex non-linear programming problem that involves minimizing vehicle fuel consumption in the vicinity of signalized intersections. The results demonstrated savings of up to 30 percent in fuel consumption within the traffic signalized intersection vicinity. The proposed system was tested in an agent-based environment developed in MATLAB using the RPA car-following model as well as the Society of Automobile Engineers (SAE) J2735 message set standards for vehicle-to-infrastructure (V2I) and vehicle-to-vehicle (V2V) communication. The results showed how multi-vehicle interaction enhances usability of the system. Simulation of a calibrated real intersection showed average fuel savings of nearly 30 percent for peak volumes. The fuel reduction was high for low volumes and decreased as the traffic volumes increased. The final testing of the algorithm was done in an enhanced Traffic Experimental Simulation tool (eTEXAS) that incorporates the conventional TEXAS model with a new web-service interface as well as connected vehicle message set dictionary. This testing was able to demonstrate model corrections required to negate the effect of system latencies as well as a demonstration of using SAE message set parsing in a connected vehicle application. Finally, the dissertation develops an integrated framework for the control of autonomous vehicle movements through intersections using a multi-objective optimization algorithm. The algorithm integrated within an existing framework that minimizes vehicle delay while ensuring vehicles do not collide. A lower-level of control is introduced that minimizes vehicle fuel consumption subject to the arrival times assigned by the upper-level controller. Results show that the eco-speed control algorithm was able to reduce the overall fuel-consumption of autonomous vehicles passing through an intersection by 15 percent while maintaining the 80 percent saving in delay when compared to a traditional signalized intersection control. / Ph. D.
2

Reliable Real-Time Communication for Future ITS (Intelligent Transport Systems) using HWA (Heterogeneous Wireless Access)

AFGHANI, AHMAD January 2011 (has links)
In this research oriented master’s thesis we have proposed a future vision of ITS (Intelligent Transport Systems) by utilizing the novel concept of HWA (Heterogeneous Wireless Access). Our proposal is backed by the investigation of the results of experiments conducted at CERES (Centre for Research on Embedded Systems), Halmstad University, Sweden to evaluate the quality of communication for V2V and V2I by using the IEEE 802.11p standard. We have also identified the expected scenarios with need of any other communication technology in replacement of IEEE 802.11p for V2V and V2I communication. We have also investigated the relevant research projects, experiments and their results on the basis of predefined constraints. In the investigated research projects the concept of HWA has been correlated with our proposal of HWA for ITS. We have identified that for smooth integration of any communication technology with IEEE 802.11p, an efficient and smart vertical handover protocol or method will be required. We have presented a blue print of a custom designed vertical handover technique which can be implemented for future ITS with further enhancements and experimental evaluations. We have also evaluated the worst case scenarios to assess the suitability of the HWA for the ITS. We proposed few solutions based on the evaluation of communication scenarios for the integration of IEEE 802.11p with other wireless communication technologies. Finally we have provided some conclusions and suggested future researches which must be conducted to realize the dream of ITS with support of HWA.
3

Effectiveness of a speed advisory traffic signal system for Conventional and Automated vehicles in a smart city

Anany, Hossam January 2019 (has links)
This thesis project presents a traffic micro simulation study that investigates the state-of-the-art in traffic management "Green Light Optimal Speed Advisory (GLOSA)" for vehicles in a smart city. GLOSA utilizes infrastructure and vehicles communication through using current signal plan settings and updated vehicular information in order to influence the intersection approach speeds. The project involves simulations for a mixed traffic environment of conventional and automated vehicles both connected to the intersection control and guided by a speed advisory traffic management system. Among the project goals is to assess the effects on traffic performance when human drivers comply to the speed advice. The GLOSA management approach is also accessed for its potential to improve traffic efficiency in a full market penetration of connected automated vehicles with enhanced capabilities such as having shorter time head ways.
4

Effectiveness of a Speed Advisory Traffic Signal System for Conventional and Automated vehicles in a Smart City

Anany, Hossam January 2019 (has links)
This thesis project investigates the state-of-the-art in traffic management "Green Light Optimal Speed Advisory (GLOSA)" for vehicles in a smart city. GLOSA utilizes infrastructure and vehicles communication through using current signal plan settings and updated vehicular information in order to influence the intersection approach speeds. The project involves traffic microscopic simulations for a mixed traffic environment of conventional and automated vehicles (AVs) both connected to the intersection control and guided by a speed advisory traffic management system. Among the project goals is to assess the effects on traffic performance when human drivers comply to the speed advice. The GLOSA management approach is accessed for its potential to improve traffic efficiency in a full market penetration of connected AVs with absolute compliance. The project also aims to determine the possible outcome resulting from enhancing the AVs capabilities such as implementing short time headways between vehicles in the future.  The best traffic performance results achieved by operating GLOSA goes for connected AVs with the lowest simulated time headway (0.3 sec). The waiting time reduction reaches 95% and trip delay lessens to 88 %.
5

Localisation et transmissions sécurisées pour la communication Véhicule à Infrastructure (V2I) : Application au service de télépéage ITS-G5 / Localization and secure transmissions for Vehicle to Infrastructure communication (V2I) : Application to the electronic toll service using the ITS-G5 technology

Randriamasy, Malalatiana 24 May 2019 (has links)
La localisation précise des véhicules et la sécurité des échanges sont deux grands axes qui font la fiabilité des services fournis dans les systèmes de transport intelligent. Ces dernières années, elles font l’objet de nombreux projets de recherche pour des champs d’application divers. Dans cette thèse, le contexte d’application est la réalisation d’un service de télépéage utilisant la technologie ITS-G5. Cette technologie de communication sans-fil permet dans un premier temps le partage des informations de sécurité routière entre les véhicules (V2V), le véhicule et l’infrastructure (V2I). Dans cette thèse, on propose une architecture permettant d’échanger des transactions de télépéage utilisant les équipements communicants en ITS-G5 embarqués dans les véhicules connectés et les unités bord de route (UBR) de l’infrastructure. Les problématiques de nos travaux de recherche se concentrent sur la méthode de localisation des véhicules ayant effectué la transaction afin de pouvoir la valider et sur la sécurité de l’architecture proposée pour assurer l’échange de cette transaction. Afin de bien localiser les véhicules lors du passage au péage, notre approche propose la compréhension de la cinématique du véhicule par une modélisation adéquate à partir des données recueillies dans les messages coopératifs (CAM : Cooperative Awareness Message) en approche du péage. Cela améliorera les informations de géolocalisation déjà présentes. Notre objectif est d’arriver à une précision de moins d’un mètre pour distinguer 2 véhicules adjacents. D’autre part, le protocole de sécurité proposé permet d’assurer l’authentification des équipements participant à l’échange et à la validation de la transaction, l’intégrité des données échangées ainsi que la confidentialité des échanges compte tenu du contexte de communication sans-fil et de la sensibilité des données échangées. Une preuve de concept de la solution de télépéage utilisant la technologie ITS-G5 est développée et intègre nos deux contributions. / The precise localization of vehicles and the security of communication are requirements that make almost of the services provided in intelligent transport systems (ITS) more reliable. In recent years, they have been the subject of numerous research projects for various fields of application. In this thesis, the context is the development of an electronic toll service using the ITS-G5 technology. This wireless communication technology initially allows the sharing of traffic safety information between vehicles (V2V), vehicle and infrastructure (V2I). In our work, we propose a tolling application using equipment operating in ITS-G5 embedded in the connected vehicles and roadside units. For this, ensuring both precise geolocation of the vehicles and security of communication are required to validate the transaction.In order to properly locate the vehicles during the toll crossing, our approach is based on the understanding of the kinematics of the vehicle through a suitable modeling from the data collected in the cooperative messages (called CAM: Cooperative Awareness Message). This approach aims to improve the geolocation information already present in the message. Our goal is to achieve vehicle localization with an accuracy lower than one meter to distinguish two adjacent vehicles. On the other hand, the proposed tolling protocol ensures the authentication of the equipment or entities involved in the exchange and the validation of the transaction, the integrity of the transmitted data as well as the confidentiality of the communication. In this way, we take into account the context of the wireless communication and the sensitivity of the exchanged data. Our two contributions are integrated in the implemented Proof of Concept of the tolling application using the ITS-G5 technology.

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