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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.
31

Cooperative perception : Application in the context of outdoor intelligent vehicle systems

Li, Hao 21 September 2012 (has links) (PDF)
The research theme of this dissertation is the multiple-vehicles cooperative perception (or cooperative perception) applied in the context of intelligent vehicle systems. The general methodology of the presented works in this dissertation is to realize multiple-intelligent vehicles cooperative perception, which aims at providing better vehicle perception result compared with single vehicle perception (or non-cooperative perception). Instead of focusing our research works on the absolute performance of cooperative perception, we focus on the general mechanisms which enable the realization of cooperative localization and cooperative mapping (and moving objects detection), considering that localization and mapping are two underlying tasks for an intelligent vehicle system. We also exploit the possibility to realize certain augmented reality effect with the help of basic cooperative perception functionalities; we name this kind of practice as cooperative augmented reality. Naturally, the contributions of the presented works consist in three aspects: cooperative localization, cooperative local mapping and moving objects detection, and cooperative augmented reality.
32

Vehicle Perception: Localization, Mapping with Detection, Classification and Tracking of Moving Objects

Vu, Trung-Dung 18 September 2009 (has links) (PDF)
Perceiving or understanding the environment surrounding of a vehicle is a very important step in building driving assistant systems or autonomous vehicles. In this thesis, we study problems of simultaneous localization and mapping (SLAM) with detection, classification and tracking moving objects in context of dynamic outdoor environments focusing on using laser scanner as a main perception sensor. It is believed that if one is able to accomplish these tasks reliably in real time, this will open a vast range of potential automotive applications. The first contribution of this research is made by a grid-based approach to solve both problems of SLAM with detection of moving objects. To correct vehicle location from odometry we introduce a new fast incremental scan matching method that works reliably in dynamic outdoor environments. After good vehicle location is estimated, the surrounding map is updated incrementally and moving objects are detected without a priori knowledge of the targets. Experimental results on datasets collected from different scenarios demonstrate the efficiency of the method. The second contribution follows the first result after a good vehicle localization and a reliable map are obtained. We now focus on moving objects and present a method of simultaneous detection, classification and tracking moving objects. A model-based approach is introduced to interpret the laser measurement sequence over a sliding window of time by hypotheses of moving object trajectories. The data-driven Markov chain Monte Carlo (DDMCMC) technique is used to solve the data association in the spatio-temporal space to effectively find the most likely solution. We test the proposed algorithm on real-life data of urban traffic and present promising results. The third contribution is an integration of our perception module on a real vehicle for a particular safety automotive application, named Pre-Crash. This work has been performed in the framework of the European Project PReVENT-ProFusion in collaboration with Daimler AG. A comprehensive experimental evaluation based on relevant crash and non-crash scenarios is presented which confirms the robustness and reliability of our proposed method.
33

Analysis and Control of High-Speed Wheeled Vehicles

Velenis, Efstathios 29 March 2006 (has links)
In this work we reproduce driving techniques to mimic expert race drivers and obtain the open-loop control signals that may be used by auto-pilot agents driving autonomous ground wheeled vehicles. Race drivers operate their vehicles at the limits of the acceleration envelope. An accurate characterization of the acceleration capacity of the vehicle is required. Understanding and reproduction of such complex maneuvers also require a physics-based mathematical description of the vehicle dynamics. While most of the modeling issues of ground-vehicles/automobiles are already well established in the literature, lack of understanding of the physics associated with friction generation results in ad-hoc approaches to tire friction modeling. In this work we revisit this aspect of the overall vehicle modeling and develop a tire friction model that provides physical interpretation of the tire forces. The new model is free of those singularities at low vehicle speed and wheel angular rate that are inherent in the widely used empirical static models. In addition, the dynamic nature of the tire model proposed herein allows the study of dynamic effects such as transients and hysteresis. The trajectory-planning problem for an autonomous ground wheeled vehicle is formulated in an optimal control framework aiming to minimize the time of travel and maximize the use of the available acceleration capacity. The first approach to solve the optimal control problem is using numerical techniques. Numerical optimization allows incorporation of a vehicle model of high fidelity and generates realistic solutions. Such an optimization scheme provides an ideal platform to study the limit operation of the vehicle, which would not be possible via straightforward simulation. In this work we emphasize the importance of online applicability of the proposed methodologies. This underlines the need for optimal solutions that require little computational cost and are able to incorporate real, unpredictable environments. A semi-analytic methodology is developed to generate the optimal velocity profile for minimum time travel along a prescribed path. The semi-analytic nature ensures minimal computational cost while a receding horizon implementation allows application of the methodology in uncertain environments. Extensions to increase fidelity of the vehicle model are finally provided.
34

Stochastic dynamic traffic assignment for intermodal transportation networks with consistent information supply strategies

Abdelghany, Khaled Faissal Said, January 2001 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2001. / Vita. Includes bibliographical references. Available also from Dissertation Abstracts.
35

Integrated information and traffic control strategies for congested urban freeway corridors /

Valdes Diaz, Didier M., January 1999 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 1999. / Vita. Includes bibliographical references (leaves 189-197). Available also in a digital version from Dissertation Abstracts.
36

Applications of vehicle location and communication technology in fleet management systems /

Wong, Chi-tak, Keith. January 2001 (has links)
Thesis (M.A.)--University of Hong Kong, 2001. / Includes bibliographical references (leaf 62).
37

An integrated methodology for the evaluation of the safety impacts of in-vehicle driver warning technologies

de Oliveira, Marcelo Gurgel 05 1900 (has links)
No description available.
38

Universal incident detection :

Zhang, Kun. Unknown Date (has links)
Road incidents and incident induced traffic congestions are a big threat to the mobility and safety of our daily life. Timely and accurate incident detection using automated incident detection (AID) systems is essential to effectively tackle incident induced congestion problems and to improve traffic management. The core of an AID system is an incident detection algorithm that interprets real time traffic data and makes decision on incidents. / Literature review of existing AID algorithms and their applications reveals that 1) there is no single freeway algorithm that can fulfil the universality aspect of incident detection which is required by the advanced traffic management systems, and 2) how to achieve the effective and stable arterial road incident detection remains a big issue of AID research. In addition, there exists a strong need for incorporating existing expert traffic knowledge into AID algorithms to enhance incident detection performance. / Thesis (PhDTransportSystemsEngineering)--University of South Australia, 2005.
39

Advanced motion control and sensing for intelligent vehicles

Li, Li, Wang, Fei-Yue. January 2007 (has links)
Mainly based on Li Li's Ph. D. dissertation: University of Arizona, Tucson, 2005. / Includes bibliographical references and index.
40

Methodologies for integrating traffic flow theory, ITS and evolving surveillance technologies /

Nam, Do H., January 1995 (has links)
Thesis (Ph. D.)--Virginia Polytechnic Institute and State University, 1995. / Vita. Abstract. Includes bibliographical references (leaves 137-140). Also available via the Internet.

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