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Model Predictive Control for Heavy Duty Vehicle Platooning / Modellbaserad prediktionsreglering för tunga fordon i fordonstågKemppainen, Josefin January 2012 (has links)
The aim of platooning is to enable several vehicles to drive in a convoy while each vehicle is controlled autonomously in longitudinal direction. All vehicles in the platoon are equipped with WiFi and can therefore apply Vehicle-to-Vehicle (V2V) communication. As a result, a short intermediate distance between the vehicles can be maintained. Reduction of the aerodynamic drag is the result of the short distance, which in turn, reduces the consumed fuel. This thesis is a part of a larger project, consisting of two other theses that investigate estimation of the sensor data. Other scenarios that may arise with the platooning concept, e.g. packet losses and time synchronization of the different sensors are also analyzed. The purpose of this master thesis is to develop and evaluate a Model Predictive Control (MPC) in the concept of platooning. The main focus lies on implementation of two types of MPC, centralized and distributed, and later on integration with the other two subsystems is performed. Results from the MPC itself are evaluated, principally in terms of fuel con- sumption and computational demand. The major part of the results are based on the complete system as one unit and covers different test scenarios such as WiFi loss and non-transmitting vehicle entering the platoon. A comparison of how much energy that is consumed by the engine between an HDV driving with its cruise control and an HDV driving in a platoon has been performed. With an intermediate distance of 10 meters, driving with varying velocity and ideal signals the energy consumption got reduced with an average of 11%. / Syftet med platooning är att flera tunga fordon kör tätt efter varandra i ett fordonståg. Varje fordon regleras autonomt i longitudinell riktning och är utrustad med WiFi. Detta bidrar till att fordonen kan kommunicera med varandra och denna kommunikation, även kallad Vehicle-to-Vehicle (V2V) - communication, leder till att det relativa avståndet mellan fordonen kan minskas, vilket i sin tur leder till minskat luftmotstånd och därmed minskad bränsleförbrukning. Detta examensarbete är en del av ett större projekt som består av ytterligare två examensarbeten. De andra två hanterar estimeringen av sensordata samt behandlar förlorat sensordata och tidssynkronisering av de olika sensorerna som används. Syftet med detta examensarbete är att utveckla och utvärdera en MPC regu- lator i platooning sammanhang. Huvudfokuset ligger på implementeringen, både centraliserad och distribuerad MPC, och integreringen med de två andra delsystemen. Resultaten från enbart MPC utvärderas i termer av bränsleförbrukning och även beräkningskapactiet, då MPC är känt för att vara väldigt beräkningskrävan- de och är ofta en begränsning för hårdvaran. Den största delen av resultaten är baserade på hela systemet och täcker olika scenarion som exempelvis dålig WiFi uppkoppling och att icke−sändande fordon intar platoonen. En jämförelse av hur mycket energi motorn förbrukade har gjorts mellan ett tungt fordon som kör med farthållaren påslagen och ett tungt fordon som kör i en platoon. Med ett relativt avstånd på 10 meter, varierande hastighet och icke brusiga signaler kan bränsleförbrukning minskas med ett medel på approximativt 11%.
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Vehicle to Vehicle Communication in Level 4 AutonomyHajimirsadeghi, Seyedsalar 01 January 2017 (has links)
With the number of deaths, commute time, and injuries constantly rising due to
human driving errors, it’s time for a new transportation system, where humans are no
longer involved in driving decisions and vehicles are the only machine that decide the
actions of a vehicle. To accomplish a fully autonomous world, it’s important for
vehicles to be able to communicate instantly and report their movements in order to
reduce accidents. This paper discusses four approaches to vehicle to vehicle
communication, as well as the underlying standards and technology that enable
vehicles to accomplish communicating.
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A RELIABILITY-BASED ROUTING PROTOCOL FOR VEHICULAR AD-HOC NETWORKSBernsen, James 01 January 2011 (has links)
Vehicular Ad hoc NETworks (VANETs), an emerging technology, would allow vehicles to form a self-organized network without the aid of a permanent infrastructure. As a prerequisite to communication in VANETs, an efficient route between communicating nodes in the network must be established, and the routing protocol must adapt to the rapidly changing topology of vehicles in motion. This is one of the goals of VANET routing protocols. In this thesis, we present an efficient routing protocol for VANETs, called the Reliable Inter-VEhicular Routing (RIVER) protocol. RIVER utilizes an undirected graph that represents the surrounding street layout where the vertices of the graph are points at which streets curve or intersect, and the graph edges represent the street segments between those vertices. Unlike existing protocols, RIVER performs real-time, active traffic monitoring and uses this data and other data gathered through passive mechanisms to assign a reliability rating to each street edge. The protocol then uses these reliability ratings to select the most reliable route. Control messages are used to identify a node’s neighbors, determine the reliability of street edges, and to share street edge reliability information with other nodes.
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An Agent-based Coordination Strategy for Information Propagation in Connected Vehicle SystemsLi, Xin January 2014 (has links)
Context. Connected vehicles use sensors such as cameras or radars to collect data about surrounding environments automatically and share these data with each other or with road side infrastructure using short-range wireless communication. Due to the large amount of information generated, strategies are required to minimize information redundancy when important information is propagated among connected vehicles. Objectives. This research aims to develop an information propagation strategy in connected vehicle systems using software agent-based coordination strategies to reduce unnecessary message broadcast and message propagation delay. Methods. A review of related work is used to acquire a deep insight as well as knowledge of the state-of-the-art and the state-of-practice from relevant studies in the subject area. Based on the review of related work, we propose an agent-based coordination strategy for information propagation in connected vehicle systems, in which connected vehicles coordinate their message broadcast activities using auctions. After that, a simulation experiment is conducted to evaluate the proposed strategy by comparing it with existing representative strategies. Results. Results of simulation experiments and statistical tests show that the proposed agent-based coordination strategy manifest some improvements in reducing unnecessary message broadcast and message propagation delay compared to other strategies involved in the simulation experiments. Conclusions. In this research, we suggest a new strategy to manage the propagation of information in connected vehicle systems. According to the small scale simulation analysis, the use of auctions to select message transmitters enables our proposed strategy to achieve some improvements in reducing unnecessary message broadcast and propagation delay than existing strategies. Thus, with the help of our proposed strategy, unnecessary message broadcast can be minimized and the communication resources of connected vehicle systems can be utilized effectively. Also, important safety messages can be propagated to drivers faster, negative traffic events could be averted. / 0707708513
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Intersection Simulation and Path EstimationMilo, Curtis January 2020 (has links)
As autonomous vehicles begin to move towards full autonomy, the controllers and software within them are becoming incredibly more complex to deal with any plausible scenario. Automotive manufacturers must balance the need for safety with the customers' desire for performance and features. A robust set of tools is a necessity to develop vehicle control protocols and navigation strategies. Vehicle to everything communication protocols and path planning are two aspects of autonomous vehicles that need a large amount of development effort. The MathWorks has put a great amount of effort in developing a robust simulation tool for autonomous vehicles. However, it currently lacks a method to develop V2X communication and path routing. In this thesis, I developed an extension for the Mathworks Simulink autonomous driving toolbox to incorporate graph-based path planning and vehicle to vehicle communication. The navigation system models each road using standard civil engineering techniques, to calculate the intersection points and bounding areas for regions of interest. Based on these regions, a directed graph is created to aid in calculating the shortest path. The navigation system also provides a redundant method for path planning for poorly marked areas and intersections. The vehicle to vehicle communication system emulates the 802.11p protocol and deals with practical challenges such as latency to provide developers with a realistic environment in which to develop vehicle communication protocols. The final result is a simulation where multiple vehicles drive safely and efficiently throughout a city network, sending messages at regions of interest and follow computed paths to their desired destinations. / Thesis / Master of Applied Science (MASc) / Vehicle to Everything communication protocols and path planning are two aspects of autonomous vehicles that need a robust framework to aid in their development. I developed an extension for the Mathworks Simulink autonomous driving toolbox to incorporate graph-based path planning and vehicle to vehicle communication. The navigation system models each road using standard civil engineering techniques, to calculate the intersection points and bounding areas for regions of interest. Based on these regions, a directed graph is created to aid in calculating the shortest path. The navigation system also provides a redundant method for path planning for poorly marked areas and intersections. The vehicle to vehicle communication system emulates the 802.11p protocol and realistic effects such as latency to provide developers with a realistic environment to develop vehicle communication protocols. The final result is a simulation where multiple vehicles drive throughout a city network, sending messages at regions of interest and follow a computed path to their desired destination.
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Probability Distribution of Rician K-Factor in Urban, Suburban and Rural Areas Using Real World Captured DataAbd-Alhameed, Raed, Jones, Steven M.R., Noras, James M., Zhu, Shaozhen (Sharon), Ghazaany, Tahereh S., Van Buren, T., Wilson, J., Suggett, T., Marker, S. 07 1900 (has links)
Yes / The Rician K-factor of the vehicle-to-vehicle (V2V) wireless propagation channel is estimated using a moment-based method on the envelope of measured pulse data. The measurements were carried out under vehicle-to-vehicle wireless communication channel condition with car rooftop antenna heights at one end of the link and very low antenna height at the other end. Data captured from typical urban, suburban and rural areas are analyzed and the K-factor probability density function is generated for each scenario to give an insight into the V2V channel behavior. For all three areas, the majority of K values are found to be within the range of -10 to +10 dB. The K-factor distributions are close to normal with mean values of 1.8, 2.6 and 3 dB respectively for urban, suburban and rural area.
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Concept of an enhanced V2X pedestrian collision avoidance system with a cost function–based pedestrian modelKotte, Jens, Schmeichel, Carsten, Zlocki, Adrian, Gathmann, Hauke, Eckstein, Lutz 29 September 2020 (has links)
Objective: State-of-the-art collision avoidance and collision mitigation systems predict the behavior of pedestrians based on trivial models that assume a constant acceleration or velocity. New sources of sensor information—for example, smart devices such as smartphones, tablets, smartwatches, etc.—can support enhanced pedestrian behavior models. The objective of this article is the development and implementation of a V2Xpedestrian collision avoidance system that uses new information sources.
Methods: A literature review of existing state-of-the-art pedestrian collision avoidance systems, pedestrian behavior models in advanced driver assistance systems (ADAS), and traffic simulations is conducted together with an analysis of existing studies on typical pedestrian patterns in traffic. Based on this analysis, possible parameters for predicting pedestrian behavior were investigated. The results led to new requirements from which a concept was developed and implemented.
Results: The analysis of typical pedestrian behavior patterns in traffic situations showed the complexity of predicting pedestrian behavior. Requirements for an improved behavior prediction were derived. A concept for a V2X collision avoidance system, based on a cost function that predicts pedestrian near future presence, and its implementation is presented. The concept presented considers several challenges such as information privacy, inaccuracies of the localization, and inaccuracies of the prediction.
Conclusion: A concept for an enhanced V2X pedestrian collision avoidance system was developed and introduced. The concept uses new information sources such as smart devices to improve the prediction of the pedestrian's presence in the near future and considers challenges that come along with the usage of these information sources.
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A Microsimulation Approach Assessing the Impact of Connected Vehicle on Work Zone Traffic SafetyGenders, Wade 06 1900 (has links)
Safety in transportation systems is of paramount concern to society; many improvements have been made in recent decades and yet thousands of fatalities still occur annually. Work zones in particular are areas with increased safety risks in transit networks. Advances in electronics have now allowed engineers to merge powerful computing and communication technologies with modern automotive and vehicular technology, known as connected vehicle. Connected vehicle will allow vehicles to exchange data wirelessly with each other and infrastructure to improve safety, mobility and sustainability. This thesis presents a paper that focuses on evaluating the impact of connected vehicle on work zone traffic safety. A dynamic route guidance system based on decaying average-travel-time and shortest path routing was developed and tested in a microscopic traffic simulation environment to avoid routes with work zones. To account for the unpredictable behaviour and psychology of driver’s response to information, three behaviour models, in the form of multinomial distributions, are proposed and studied in this research. The surrogate safety measure improved Time to Collision was used to gauge network safety at various market penetrations of connected vehicles. Results show that higher market penetrations of connected vehicles decrease network safety due to increased average travel distance, while the safest conditions, 5%-10% reduction in critical Time to Collision events, were observed at market penetrations of 20%-40% connected vehicle, with network safety strongly influenced by behaviour model. / Thesis / Master of Applied Science (MASc)
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SIMULATION-BASED PERFORMANCE COMPARISONS OF GEOCAST ROUTING PROTOCOLSHequn, Zhang, Rui, Wang January 2014 (has links)
Intelligent Transportation System (ITS) is the main research domain for making road transport safer and more comfortable. For the sake of increasing the benefits of ITS, projects about Inter-Vehicle Communication (IVC) system have been proposed to make communications among vehicles possible, to exchange traffic information and avoid accidents. In order to create communication network among vehicles or between vehicles and infrastructure, Vehicular Ad hoc Networks (VANETs) has been proposed. Many applications in VANETs need to send messages to vehicles within a specific geographic region. This behavior is called geocast and this specific geographic region is called the Zone of Relevance (ZOR). Some routing protocols which are related to Geocast have been proposed in literature for VANETs. So it is significant to evaluate and compare the performance of these known Geocast routing protocols. In this thesis, categories of the routing protocols, as well as communication forwarding schemes are introduced. The routing protocols in VANETs are also summarized and compared. In order to evaluate the performance of these protocols, the evaluation methods are proposed and then a Geocast routing simulator is designed and used to simulate the Geocast network environment and several Geocast routing protocols.
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Development and evaluation of advanced traveler information system (ATIS) using vehicle-to-vehicle (V2V) communication systemKim, Hoe Kyoung 15 January 2010 (has links)
This research develops and evaluates an Advanced Traveler Information System (ATIS) model using a Vehicle-to-Vehicle (V2V) communication system (referred to as the GATIS-V2V model) with the off-the-shelf microscopic simulation model, VISSIM. The GATIS-V2V model is tested on notional small traffic networks (non-signalized and signalized) and a 6X6 typical urban grid network (signalized traffic network). The GATIS-V2V model consists of three key modules: vehicle communication, on-board travel time database management, and a Dynamic Route Guidance System (DRGS). In addition, the system performance has been enhanced by applying three complementary functions: Autonomous Automatic Incident Detection (AAID), a minimum sample size algorithm, and a simple driver behavior model. To select appropriate parameter ranges for the complementary functions a sensitivity analysis has been conducted. The GATIS-V2V performance has been investigated relative to three underlying system parameters: traffic flow, communication radio range, and penetration ratio of participating vehicles. Lastly, the enhanced GATIS-V2V model is compared with the centralized traffic information system.
This research found that the enhanced GATIS-V2V model outperforms the basic model in terms of travel time savings and produces more consistent and robust system output under non-recurrent traffic states (i.e., traffic incident) in the simple traffic network. This research also identified that the traffic incident detection time and driver's route choice rule are the most crucial factors influencing the system performance. As expected, as traffic flow and penetration ratio increase, the system becomes more efficient, with non-participating vehicles also benefiting from the re-routing of participating vehicles. The communication radio ranges considered were found not to significantly influence system operations in the studied traffic network. Finally, it is found that the decentralized GATIS-V2V model has similar performance to the centralized model even under low flow, short radio range, and low penetration ratio cases. This implies that a dynamic infrastructure-based traffic information system could replace a fixed infrastructure-based traffic information system, allowing for considerable savings in fixed costs and ready expansion of the system off of the main network corridors.
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