Auswahl der wissenschaftlichen Literatur zum Thema „Application au Platooning“

Truck platooning has been identified as an emerging and promising operational technology with the advantages of fuel consumption savings and carbon emissions reductions. We formulate the truck platooning routing optimization problem as a multi-commodity network flow problem from a transportation optimization and scheduling perspective. Based on fuel consumption savings generated through the reduction of aerodynamic drag by the formation of truck platooning, the route of each truck is also set to be a decision variable needing settlement to facilitate the formation of truck platooning to maximize fuel consumption savings. Considering fuel consumption and detour costs, we construct a truck platooning routing optimization model with minimum overall system fuel consumption as the optimization objective. The output of the routing optimization model could both reflect the composition of each truck platooning on each link and directly show the routings of each truck. To explore the impact of the restrictions on the number of trucks in truck platooning on overall fuel consumption savings, road networks are constructed and the truck platooning routing optimization model is solved by the commercial solver CPLEX. Compared to individual trucks, 8% or 12% fuel consumption savings are achieved, respectively, with the number of trucks being restricted or not restricted in truck platooning. Considering the different fuel reduction rates of the following trucks in platooning on the system performance in terms of the total fuel cost, a sensitivity analysis is also conducted. The results also show that the ideal truck platooning routing plan can be obtained by the proposed model, and the study provides a theoretical reference for the promotion and application of truck platooning.

Since 2016 federated learning (FL) has been an evolving topic of discussion in the artificial intelligence (AI) research community. Applications of FL led to the development and study of federated reinforcement learning (FRL). Few works exist on the topic of FRL applied to autonomous vehicle (AV) platoons. In addition, most FRL works choose a single aggregation method (usually weight or gradient aggregation). We explore FRL's effectiveness as a means to improve AV platooning by designing and implementing an FRL framework atop a custom AV platoon environment. The application of FRL in AV platooning is studied under two scenarios: (1) Inter-platoon FRL (Inter-FRL) where FRL is applied to AVs across different platoons; (2) Intra-platoon FRL (Intra-FRL) where FRL is applied to AVs within a single platoon. Both Inter-FRL and Intra-FRL are applied to a custom AV platooning environment using both gradient and weight aggregation to observe the performance effects FRL can have on AV platoons relative to an AV platooning environment trained without FRL. It is concluded that Intra-FRL using weight aggregation (Intra-FRLWA) provides the best performance for controlling an AV platoon. In addition, we found that weight aggregation in FRL for AV platooning provides increases in performance relative to gradient aggregation. Finally, a performance analysis is conducted for Intra-FRLWA versus a platooning environment without FRL for platoons of length 3, 4 and 5 vehicles. It is concluded that Intra-FRLWA largely out-performs the platooning environment that is trained without FRL.

The advent of autonomous vehicles has opened new horizons for transportation efficiency and safety. Platooning, a strategy where vehicles travel closely together in a synchronized manner, holds promise for reducing traffic congestion, lowering fuel consumption, and enhancing overall road safety. This article explores the application of Multi-Agent Reinforcement Learning (MARL) combined with Proximal Policy Optimization (PPO) to optimize autonomous vehicle platooning. We delve into the world of MARL, which empowers vehicles to communicate and collaborate, enabling real-time decision making in complex traffic scenarios. PPO, a cutting-edge reinforcement learning algorithm, ensures stable and efficient training for platooning agents. The synergy between MARL and PPO enables the development of intelligent platooning strategies that adapt dynamically to changing traffic conditions, minimize inter-vehicle gaps, and maximize road capacity. In addition to these insights, this article introduces a cooperative approach to Multi-Agent Reinforcement Learning (MARL), leveraging Proximal Policy Optimization (PPO) to further optimize autonomous vehicle platooning. This cooperative framework enhances the adaptability and efficiency of platooning strategies, marking a significant advancement in the pursuit of intelligent and responsive autonomous vehicle systems.

Truck platooning involves a small convoy of freight vehicles using electronic coupling as an application in automated driving technology, and it is expected to represent a major solution for improving efficiency in truck transportation in the near future. Recently, there have been several trials regarding truck platooning with major truck manufacturers and logistics companies on public roads in the United States, European countries and Japan. There is a need to locate a facility for the formation of truck platooning to realize the unmanned operation of trucks following in a platoon. In this study, we introduce the current status of truck platooning in Japan and present the optimal location model for truck platooning using the continuous approximation model with a numerical experiment, considering the case in Japan. We derived the optimal locational strategy for the combination of the long-haul ratio and the cost factor of platooning. With parameters estimated for several scenarios for the deployment of truck platooning in Japan, the numerical results show that the optimal locational strategy for a platoon of manned vehicles and a platoon with unmanned following vehicles is the edge of the local region, and that for a platoon of fully automated vehicles is the center of the region.

Heavy duty vehicle platooning under highway operating conditions has been projected to provide significant fuel economy gains based on aerodynamic drag improvements of the platooning vehicles. Realizing these benefits and the economic viability under real-world operating conditions presents several challenges. The objective of this paper (the third as part of a series) is to analytically quantify the payback and profitability of heavy-duty vehicles platooning across the U.S. Interstate highway system. In this paper, a rigorous assessment of several factors that influence the platooning system payback for an end-user as well as the revenue potential for suppliers who may be utilizing an equipment lease model dependent on end-user savings, is presented. In this assessment key interactions explored include market adoption rates, platooning velocities, platoon-able daily mileage, platooning likelihood, variations in baseline powertrain fuel economy (diesel or electric), price of fuel (diesel or electricity), platooning fuel economy benefits, price of the added technology, and the impact of natural platooning due to traffic interactions. Further, the paper explores the economic impact of higher levels of vehicle automation for the trailing vehicles in the platoon, where extending the driver Hours of Service (HoS) may provide additional financial benefits. While the approach makes use of a limited fidelity vehicle analytical model for longitudinal dynamics and operations economics, the narrative provides application decision personnel with a mechanism and well-defined set of impact factors to consider as part of their architectural selection process.

This paper presents a cooperative control method for connected and automated vehicle (CAV) platooning, thus specifically addressing the challenge of sensor measurement errors that can disrupt the stability of the CAV platoon. Initially, the state-space equation of the CAV platooning system was formulated, thereby taking into account the measurement error of onboard sensors. The superposition effect of the sensor measurement errors was statistically analyzed, thereby elucidating its impact on cooperative control in CAV platooning. Subsequently, the application of a Kalman filter was proposed as a means to mitigate the adverse effects of measurement errors. Additionally, the CAV formation control problem was transformed into an optimal control decision problem by introducing an optimal control decision strategy that does not impose pure state variable inequality constraints. The proposed method was evaluated through simulation experiments utilizing real vehicle trajectory data from the Next Generation Simulation (NGSIM). The results demonstrate that the method presented in this study effectively mitigates the influence of measurement errors, thereby enabling coordinated vehicle-following behavior, achieving smooth acceleration and deceleration throughout the platoon, and eliminating traffic oscillations. Overall, the proposed method ensures the stability and comfort of the CAV platooning formation.

Vehicle platoons involve groups of vehicles travelling together at a constant inter-vehicle distance, with different common benefits such as increasing road efficiency and fuel saving. Vehicle platooning requires highly reliable wireless communications to keep the group structure and carry out coordinated maneuvers in a safe manner. Focusing on infrastructure-assisted cellular vehicle to anything (V2X) communications, the amount of control information to be exchanged between each platoon vehicle and the base station is a critical factor affecting the communication latency. This paper exploits the particular structure and characteristics of platooning to decrease the control information exchange necessary for the channel acquisition stage. More precisely, a scheme based on radio environment map (REM) reconstruction is proposed, where geo-localized received power values are available at only a subset of platoon vehicles, while large-scale channel parameters estimates for the rest of platoon members are provided through the application of spatial Ordinary Kriging (OK) interpolation. Distinctive features of the vehicle platooning use case are explored, such as the optimal patterns of vehicles within the platoon with available REM values for improving the quality of the reconstruction, the need for an accurate semivariogram modeling in OK, or the communication cost when establishing a centralized or a distributed architecture for achieving REM reconstruction. The evaluation results show that OK is able to reconstruct the REM in the platoon with acceptable mean squared estimation error, while reducing the control information for REM acquisition in up to 64% in the best-case scenario.

This work aims at developing and testing a novel Coalitional Distributed Model Predictive Control (C-DMPC) strategy suitable for vehicle platooning applications. The stability of the algorithm is ensured via the terminal constraint region formulation, with robust positively invariant sets. To ensure a greater flexibility, in the initialization part of the method, an invariant table set is created containing several invariant sets computed for different constraints values. The algorithm was tested in simulation, using both homogeneous and heterogeneous initial conditions for a platoon with four homogeneous vehicles, using a predecessor-following, uni-directionally communication topology. The simulation results show that the coalitions between vehicles are formed in the beginning of the experiment, when the local feasibility of each vehicle is lost. These findings successfully prove the usefulness of the proposed coalitional DMPC method in a vehicle platooning application, and illustrate the robustness of the algorithm, when tested in different initial conditions.

Cloud-Assisted Connected and Autonomous Vehicles (CCAV) are set to revolutionise road safety, providing substantial societal and economic advantages. However, with the evolution of CCAV technology, security and privacy threats have increased. Although several studies have been published around the threat and risk estimation aspects of CCAV, limited research exists on the security implications and emerging threat landscapes in the CCAV platooning application. We conducted an extensive review and categorisation of real-world security incidents and created an account of 132 threats from scholarly sources and 64 threats from recorded events in practice. Furthermore, we defined thirty-one (31) trust domains and outlined eight (8) unique attack vectors to supplement existing research efforts for the systematic security analysis of such cyberinfrastructures. Using these findings, we create a detailed attack taxonomy to communicate threat-related information in CCAV and platooning applications and highlight emerging challenges and ways to safeguard the broader CCAV systems. This work acts as a roadmap to existing researchers and practitioners advocating for a ‘security and privacy by design’ framework for a dynamically evolving CCAV threat landscape.

Vehicular ad-hoc networks (VANET) enable vehicles to exchange information on traffic conditions, dynamic status and localization, to enhance road safety and transportation efficiency. A typical VANET application is platooning, which can take advantage of exchanging information on speed, heading and position to allow shorter inter-vehicle distances without compromising safety. However, the platooning performance depends drastically on the quality of the communication channel, which in turn is highly influenced by the medium access control protocol (MAC). Currently, VANETs use the IEEE 802.11p MAC, which follows a carrier sense multiple access with collision avoidance (CSMA/CA) policy that is prone to collisions and degrades significantly with network load. This has led to recent proposals for a time-division multiple access (TDMA)-based MAC that synchronize vehicles’ beacons to prevent or reduce collisions. In this paper, we take CSMA/CA and two TDMA-based overlay protocols, i.e., deployed over CSMA/CA, namely PLEXE-slotted and RA-TDMAp, and carry out extensive simulations with varying platoon sizes, number of occupied lanes and transmit power to deduce empirical models that provide estimates of average number of collisions per second and average busy time ratio. In particular, we show that these estimates can be obtained from observing the number of radio-frequency (RF) neighbours, i.e., number of distinct sources of the packets received by each vehicle per time unit. These estimates can enhance the online adaptation of distributed applications, particularly platooning control, to varying conditions of the communication channel.

Cette thèse présente une exploration complète de la conception d’observateurs avancés pour les systèmes de véhicules terrestres, en mettant particulièrement l’accent sur l’intégration de techniques de réseaux neuronaux pour relever les défis liés à la dynamique non linéaireet aux complexités de mesure. La recherche est systématiquement divisée en trois parties distinctes, chacune se concentrant sur un aspect spécifique de la conception d’observateurset de leur application pratique aux véhicules terrestres.La première partie introduit une conception d’observateur novatrice utilisant un réseau neuronal multicouche pour les véhicules terrestres autonomes. Ce segment de l’étude propose un observateur en réseau neuronal continu-discret (NSNNO), particulièrement adapté aux systèmes caractérisés par une non-linéarité significative et sans nécessité de connaissances préalables sur la dynamique du système. L’observateur, conçu comme un réseau neuronal feedforward à trois couches, est méticuleusement entraîné en utilisant l’algorithme d’apprentissage par rétropropagation de l’erreur, amélioré par un terme de modification e pour la robustesse. Cette partie aborde efficacement les défis associés à la mesure en temps discret dans les systèmes de véhicules.La deuxième partie se penche sur l’amélioration de l’estimation de l’état dans la dynamique des véhicules terrestres grâce à l’application de réseaux neuronaux à fonction de base radiale (RBF). Cette section est articulée à travers trois articles pivots, chacun apportant une perspective et une solution uniques. Ces articles abordent collectivement divers défis en matière de mesure et de modélisation, démontrant la polyvalence et l’efficacité des réseaux RBF dans l’estimation de la dynamique complexe des véhicules.La troisième partie s’appuie sur la conception réussie d’observateurs basés sur des réseaux neuronaux pour des véhicules terrestres individuels et étend leur application au contexte du pelotonnage de véhicules sous des mesures retardées. Cette partie de la recherche se concentre sur les défis uniques inhérents à l’environnement de pelotonnage, en particulier l’impact des retards de communication entre les véhicules. Elle montre comment les conceptions d’observateurs avancés peuvent être adaptées à l’environnement interconnecté et dynamique des pelotons de véhicules, garantissant la stabilité et la précision de la formation, même en présence de retards de communication.Dans l’ensemble, cette thèse apporte une contribution significative au domaine des systèmes de contrôle de véhicules terrestres, offrant des perspectives précieuses et des solutions pratiques pour le développement de systèmes d’observateurs avancés et fiables capables de naviguer dans les complexités de la dynamique véhiculaire moderne
This thesis explores advanced observer designs to improve state estimation and system performance in vehicle dynamic environments. The research is divided into three parts, where each part focuses on a specific aspect of observer design and its practical application to ground vehicles.Part One introduces a novel observer design using a multi-layer neural network for autonomous ground vehicles. This part of the study proposes a continuous-discrete time neural network observer, that is designed for systems that have significant non-linearity and without the necessity for prior knowledge of system dynamics. The observer, which is designed as a three-layer feedforward neural network, trained using the error backpropagation learning algorithm, and enhanced with an e-modification term for robustness. A closed-loop output predictor is added to the design of the neural network observer to solve the challenge of discrete time measurement in vehicle systems.Part two of this thesis introduces a novel approach using radial basis function neural networks, which is used to enhance observer designs for nonlinear dynamic systems. In this part, we propose a new weight updating function that improves the performance of RBF networks, which was designed for systems with both partially or completely unknown dynamics. The proposed observers are also designed to manage the discrete-time measurements with delay measurements to ensure accurate state estimation and improved performance of the system under these conditions.Part Three focuses on robust platooning in multi-agent systems to address the challenges that are posed by internal and communication delays, measurements uncertainties, and the system heterogeneity. A consensus-based high-gain observer and a novel-based observer are presented to enhance the stability and coordination of platoons under different conditions. These methods here are validated by extensive simulations that shows the efficiency of the observers to maintain synchronization and robustness under challenging scenarios.Overall, this thesis contributes in the field of ground vehicle control systems that offers valuable understanding and practical solutions for developing advanced observer systems that are capable of solving the complexities of modern vehicle dynamics

L'objectif de cette thèse CIFRE est de contribuer à la communication véhiculaire autonome et au développement de la mobilité urbaine. Les travaux sont basés sur les limitations et défis de la communication par radio pour les applications de sécurité et envisagent de déployer le système d'éclairage des véhicules en tant que solution de communication de soutien pour le platooning d'IVC-activées par VC Véhicules autonomes. L'objectif principale de cette recherche doctorale consiste à intégrer le système VLC dans l'architecture existante de C-ITS en développant un prototype VLC, ainsi que des algorithmes de transfert suffisants permettant VLC, RF et des solutions basées sur la perception afin d'assurer les exigences de sécurité maximales et l'échange continu d'informations entre les véhicules. La faisabilité et l'efficacité de la mise en oeuvre du système et des algorithmes de transfert ont fait l'objet de recherches approfondies sur six chapitres, destinés à faciliter une progression logique des matériaux et permettre un accès relativement facile. En plus de l'amélioration de la capacité routière en utilisant les systèmes de conduite autonome à la base de convoi. Les simulations réalisées ainsi que les résultats expérimentaux ont montré que l'intégration de VLC avec les solutions existantes RF a un avantage certain dans la qualité du canal de communication et les exigences de sécurité d'un système de platooning quand un algorithme approprié est utilisé
This thesis effort contributes to the autonomous vehicular communication and urban mobility improvements. The work addresses the main radio-based V2V communication limitations and challenges for ITS hard-safety applications and intends to deploy the vehicular lighting system as a supportive communication solution for platooning of IVC-enabled autonomous vehicles. The ultimate objectives of this Ph.D research are to integrate the VLC system within the existing C-ITS architecture by developing a VLC prototype, together with sufficient, hand-over algorithms enabling VLC, RF, and perception-based solutions in order to ensure the maximum safety requirements and the continuous information exchange between vehicles. The feasibility and efficiency of the VLC-RF system implementation and hand-over algorithms were subjects to deep investigations over six self-contained chapters meant to facilitate a logical progression of materials and to enable a relatively easy access. In addition to the improvement in road capacity by utilizing the convoy-based autonomous driving systems. The carried out simulations followed-up by experimental results proved that the integration of VLC with the existed RF solutions lead to a definite benefit in the communication channel quality and safety requirements of a platooning system when a proper hand-over algorithm is utilized

[EN] In recent years, advances in wireless technologies and improved sensing and computational capabilities have led to a gradual transition towards Intelligent Transportation Systems (ITS) and related applications. These applications aim at improving road safety, provide smart navigation, and eco-friendly driving. Vehicular Ad hoc Networks (VANETs) provide a communication structure for ITS by equipping cars with advanced sensors and communication devices that enable a direct exchange of information between vehicles. Different types of ITS applications rely on two types of messages: periodic beacons and event-driven messages. Beacons include information such as geographical location, speed, and acceleration, and they are only disseminated to a close neighborhood. Differently from beacons, event-driven messages are only generated when a critical event of general interest occurs, and it is spread within a specific target area for the duration of the event. The reliability of information exchange is one of the main issues for vehicularcommunications since the safety of people on the road is directly related to the effectiveness of these transmissions. A Medium Access Control (MAC) protocol must guarantee reliable beacon broadcasting within deadline bounds to all vehicles in the neighbourhood, thereby providing them timely notifications about unsafe driving conditions or other hazardous events. Moreover, infotainment and comfort applications require reliable unicast transmissions that must be taken into account. However, high node mobility, highly dynamic topology, and lack of a central control unit, are issues that make the design of a reliable MAC protocol for vehicular environments a very difficult and challenging task, especially when efficient broadcasting strategies are required. The IEEE 802.11p MAC protocol, an approved amendment to the IEEE 802.11 standard, is a random access protocol that is unable to provide guaranteed delay bounds with sufficient reliability in vehicular scenarios, especially under high channel usage. This problem is particularly serious when implementing (semi-) automated driving applications such as platooning, where inter-vehicle spacing is drastically reduced, and the control loop that manages and maintains the platoon requires frequent, timely and reliable exchange of status information (beacons). In this thesis novel protocols compatible with the IEEE 802.11 and 802.11p standards are proposed in order to optimally adjust the contention window size for unicast applications in Mobile Ad hoc Networks (MANETs) and VANETs. Experimental tests comparing our proposals to existing solutions show that the former are able to improve the packet delivery ratio and the average end-to-end delay for unicast applications. Concerning efficient message diffusion (broadcast) in VANET environments, we proposed token-based MAC solutions to improve the performance achieved by existing 802.11p driving safety applications in different vehicular environments, including highway, urban, and platooning scenarios. Experimental results show that the proposed solutions clearly outperform 802.11p when delay-bounded beacons and event notifications must be delivered.
[ES] Recientemente, los avances en las tecnologías inalámbricas y las mejoras en términos de capacidades de sensorización y computación de los dispositivos electrónicos, han dado lugar a una transición gradual hacia servicios y aplicaciones de los Sistemas Inteligentes de Transporte (ITS). Estas aplicaciones tienen como objetivo mejorar la seguridad vial, proporcionar una navegación inteligente, y promover la conducción eco-eficiente. Las redes vehiculares ad hoc (VANETs) proporcionan una infraestructura de comunicaciones para ITS al equipar los coches con sensores avanzados y dispositivos de comunicación que permiten el intercambio directo de información entre vehículos. Los diferentes tipos de aplicaciones ITS se basan en dos tipos de mensajes: mensajes periódicos conocidos como beacons y mensajes asociados a eventos. Los mensajes periódicos incluyen información relativa a la ubicación geográfica, la velocidad y la aceleración, entre otros, y sólo son distribuidos entre los vehículos vecinos. A diferencia de estos beacons, los mensajes asociados a eventos sólo se generan cuando se produce un evento crítico de interés general, el cual se propaga dentro del área de interés de dicho evento y mientras éste siga activo. La fiabilidad del intercambio de información es uno de los principales problemas para las comunicaciones vehiculares, debido principalmente a que las aplicaciones de seguridad dependen directamente de la eficacia de estas transmisiones. Un protocolo de Control de Acceso al Medio (MAC) debe garantizar la difusión fiable de información a todos los vehículos vecinos dentro de unos límites máximos de retardo, proporcionándoles las notificaciones oportunas respecto a condiciones de conducción inseguras y otros eventos peligrosos. Por otra parte, las aplicaciones de información y entretenimiento, así como las aplicaciones orientadas al confort, también requieren transmisiones fiables extremoa-extremo. Sin embargo, la alta movilidad de los vehículos, la variabilidad de la topología, así como la falta de una unidad central de control, son factores que hacen que el diseño de un protocolo MAC fiable para entornos vehiculares sea una tarea especialmente compleja, especialmente cuando son necesarias estrategias de difusión eficientes. El protocolo MAC IEEE 802.11p, una modificación ya aprobada al estándar IEEE 802.11 original para entornos de comunicación vehiculares, es un protocolo de acceso que no es capaz de garantizar unos límites de retardo con la fiabilidad necesaria para estos entornos, especialmente en escenarios de alta utilización del canal inalámbrico. Este problema es particularmente importante a la hora de implementar aplicaciones de conducción (semi-)automática, como el caso de grupos de vehículos donde la separación entre vehículos se reduce drásticamente, y el sistema de control que gestiona y mantiene el grupo requiere de un intercambio frecuente de información fiable y acotado en retardo. En esta tesis se proponen nuevos protocolos MAC compatibles con los estándares IEEE 802.11 y 802.11p basados en el ajuste del tamaño de la ventana de contención para aplicaciones unicast en rede MANETs y VANETs. Los resultados experimentales obtenidos comparando nuestras propuestas con las soluciones existentes muestran que los protocolos propuestos son capaces de mejorar la tasa de entrega de paquetes y el retardo medio extremo-a-extremo para aplicaciones unicast. En lo que respecta a la difusión eficiente de mensajes broadcast en entornos VANET, se han propuesto soluciones MAC basadas en el uso de tokens que mejoran las prestaciones de aplicaciones de conducción segura basadas en el estándar 802.11p, tanto en autopistas, zonas urbanas, y escenarios con grupos de vehículos. Los resultados experimentales muestran que las soluciones propuestas superan claramente al protocolo 802.11p cuando es necesario entregar mensajes y notificaciones de eventos con restricc
[CAT] Recentment, els avan en les tecnologies sense fils i les millores en termes de capacitats de sensorització i computació dels dispositius electrònics, han donat lloc a una transició gradual cap a serveis i aplicacions dels sistemes intelligents de transport (ITS). Aquestes aplicacions tenen com a objectiu millorar la seguretat vial, proporcionar una navegació intelligent, i promoure la conducció ecoeficient. Les xarxes vehiculars ad hoc (VANET) proporcionen una infraestructura de comunicacions per a ITS, ja que equipen els cotxes amb sensors avançats i dispositius de comunicació que permeten l'intercanvi directe d'informació entre vehicles. Els diversos tipus d'aplicacions ITS es basen en dos classes de missatges: missatges periòdics coneguts com a beacons i missatges associats a esdeveniments. Els missatges periòdics inclouen informació relativa a la ubicació geogràfica, la velocitat i l'acceleració, entre uns altres, i només són distribuïts entre els vehicles veïns. A diferència d'aquests beacons, els missatges associats a esdeveniments només es generen quan es produeix un esdeveniment crític d'interès general, el qual es propaga dins de l àrea d'interès d'aquest esdeveniment i mentre aquest seguisca actiu. La fiabilitat de l'intercanvi d'informació és un dels principals problemes per a les comunicacions vehicular, principalment perquè les aplicacions de seguretat depenen directament de l'eficàcia d'aquestes transmissions. Un protocol de control d'accés al medi (MAC) ha de garantir la difusió fiable d'informació a tots els vehicles veïns dins d'uns límits màxims de retard, i proporcionar-los les notificacions oportunes respecte a condicions de conducció insegures i altres esdeveniments perillosos. D'altra banda, les aplicacions d'informació i entreteniment, com també les aplicacions orientades al confort, també requereixen transmissions fiables extrema-extrem. No obstant això, l'alta mobilitat dels vehicles, la variabilitat de la topologia, i la falta d'una unitat central de control, són factors que fan que el disseny d'un protocol MAC fiable per a entorns vehiculars siga una tasca especialment complexa, especialment quan són necessàries estratègies de difusió eficients. El protocol MAC IEEE 802.11p, una modificació ja aprovada a l'estàndard IEEE 802.11 original per a entorns de comunicació vehiculars, és un protocol d'accés que no és capa garantir uns límits de retard amb la fiabilitat necessària per a aquests entorns, especialment en escenaris d'alta utilització del canal sense fil. Aquest problema és particularment important a l'hora d'implementar aplicacions de conducció (semi)automàtica, com el cas de grups de vehicles en què la separació entre vehicles es redueix dràsticament, i el sistema de control que gestiona i manté el grup requereix un intercanvi freqüent d'informació fiable i delimitat en retard. En aquesta tesi es proposen nous protocols MAC compatibles amb els estàndards IEEE 802.11 i 802.11p basats en l'ajust de les dimensions de la finestra de contenció per a aplicacions unicast en xarxes MANET i VANET. Els resultats experimentals obtinguts comparant les nostres propostes amb les solucions existents mostren que els protocols proposats són capa de millorar la taxa de lliurament de paquets i el retard mitjà extrem-a-extrem per a aplicacions unicast. Pel que fa a la difusió eficient de missatges broadcast en entorns VANET, s'han proposat solucions MAC basades en l'ús de tokens que milloren les prestacions d'aplicacions de conducció segura basades en l'estàndard 802.11p, tant en autopistes, zones urbanes, i escenaris amb grups de vehicles. Els resultats experimentals mostren que les solucions proposades superen clarament el protocol 802.11p quan cal lliurar missatges i notificacions d'esdeveniments amb restriccions de latència.
Balador, A. (2016). Design and Evaluation of Efficient Medium Access Control Solutions for Vehicular Environments [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/64073
TESIS

AbstractThis chapter presents the application of the fuel assessment methodology developed in the Connecting Austria project. Thereby, a route analysis for an Austrian fleet operator is performed including the assessment of feasible and economic viable routes and scenarios. Furthermore, potential fuel consumption and CO$$_{2}$$ 2 emission savings are discussed within the given case. The saving potential may be increased via dynamic C-ITS-based truck platoon regulations, instead of statically defined, too restrictive regulations as indicated in the C-ITS assessment section. Finally, the chapter discusses the effect of truck platooning on increasing traffic efficiency.

AbstractIn 2017, the Connecting Austria project was internationally unique with respect to the special consideration of the infrastructure and traffic perspective as well as the special consideration of investigating an urban truck platooning use case with traffic-light-controlled intersections before and after motorway entrances. The three main target groups of the project were: (1) road operators/infrastructure providers, (2) logistics operators and (3) C-ITS industry. Especially for those target groups and policy maker faced one central question at that point in time —“How can safe truck platooning reduce CO$$_{2}$$ 2 -emissions and how can this help to strengthen the stakeholders’ role in their market or political environment?”. Cooperative, connected and automated mobility shape the future of road transport. Thereby, truck platooning represents an important application case in the transport logistics domain. In this chapter, the research and evaluation results presented in this book are discussed along the following three fundamental pillars: (1) traffic safety and legal issues, (2) sustainability and (3) truck platooning deployment. Finally, limitations and cultural blind spots experienced within international workshops and discussions in the context of the Connecting Austria project are reflected.

AbstractThis chapter outlines the methodologies required to realise a comprehensive scenario-based approach for effective and efficient development and validation of complex, cooperative control functions in connected and automated driving. These methods are exemplified for platooning and are devised in the scope of Connecting Austria, the Austrian flagship project on automated driving and goods transport. The development and validation approach have first been implemented vertically in depths for the intersection use cases of Connecting Austria. The scenario-based approach includes The systematic identification, collection and collocation of the relevant and representative traffic scenarios. The modelling and simulation of the according traffic and vehicle control strategies. The effectiveness assessment of the traffic and vehicle control strategies with the help of suitable key performance indicators. The controlled iterative adaption to new situations and boundary conditions by steady extension of the operational design domain within an adaptive, learning framework. The demonstration use case “intersection” is the most complex with respect to possible C-ITS, traffic and vehicle control actions. That way generality should be guaranteed, enabling a quick, horizontal extension to further use cases and scenarios, aiming to cover all relevant situations for platooning vehicles within their operational design domain. The application of all methods introduced here will be demonstrated in Chap. 10.1007/978-3-030-88682-0_9.

AbstractThis chapter outlines the methodologies required to realise a comprehensive scenario-based approach for effective and efficient development and validation of complex, cooperative control functions in connected and automated driving. These methods are exemplified for platooning and are devised in the scope of Connecting Austria, the Austrian flagship project on automated driving and goods transport. The development and validation approach have first been implemented vertically in depths for the intersection use cases of Connecting Austria. The scenario-based approach includes The systematic identification, collection and collocation of the relevant and representative traffic scenarios. The modelling and simulation of the according traffic and vehicle control strategies. The effectiveness assessment of the traffic and vehicle control strategies with the help of suitable key performance indicators. The controlled iterative adaption to new situations and boundary conditions by steady extension of the operational design domain within an adaptive, learning framework. The demonstration use case “intersection” is the most complex with respect to possible C-ITS, traffic and vehicle control actions. That way generality should be guaranteed, enabling a quick, horizontal extension to further use cases and scenarios, aiming to cover all relevant situations for platooning vehicles within their operational design domain. The application of all methods introduced here will be demonstrated in Chap. 10.1007/978-3-030-88682-0_9.

AbstractEmbedded systems are being increasingly used in changing environments where they no longer fulfill their associated stakeholder goals on their own, but rather in interaction with other embedded systems. This transition to networked, collaborative embedded systems is creating new application opportunities that impose numerous challenges for developers of these systems. In this introductory chapter of the book, we present the complexity of these systems and the challenges associated with them in a coherent manner. We illustrate the challenges using two use cases, “Vehicle Platooning” and “Adaptable and Flexible Factory.” Finally, we reference the challenges of developing collaborative embedded systems to the individual chapters of this book, which describe various methods of mastering the complexity in more detail.

In this paper, the vehicle platooning literature published between 1994 and 2010 is categorized and discussed. The paper includes a general introduction and overview of vehicle platooning and a technical description of the methodology. Recent trends in Vehicle Platooning are presented and discussed. The results are reviewed and the vehicle platooning literature is categorized into subcategories within the broader division of application focused and theory focused results. Issues and challenges faced in platooning are discussed.

<div class="section abstract"><div class="htmlview paragraph">Platooning vehicles present novel pathways to saving fuel during transportation. With the rise of autonomous solutions, platooning becomes an increasingly apparent sector requiring the application of this new technology. Platooning vehicles travel together intending to reduce aerodynamic resistance during operation. Drafting allows following vehicles to increase fuel economy and save money on refueling, whether that be at the pump or at a charging station. However, autonomous solutions are still in infancy, and controller evaluation is an exciting challenge proposed to researchers. This work brings forth a new application of an emissions quantification metric called vehicle-specific power (VSP). Rather than utilize its emissions investigative benefits, the present work applies VSP to heterogeneous Class 8 Heavy-Duty truck platoons as a means of evaluating the efficacy of Cooperative Adaptive Cruise Control (CACC). VSP creates a bridge between types of passenger vehicles to compare emission rates via estimating powertrain effort to maintain current conditions (speed, acceleration, road grade, etc.). In this study, different controller strategies and platoon configurations are examined to determine the applicability of VSP to controller evaluation. Experiments were completed at the National Center for Asphalt Technology (NCAT) circuitous track, the American Center for Mobility’s (ACM) freeway loop, and a straight section of NCAT’s track dubbed “ideal” for platooning efficiency. One truck is analyzed and compared to a lead truck, where VSP traces are calculated at each time step of experimentation. The influence of road grade, platoon size, and platooning position is considered in this study. Because the calculation of VSP considers an isolated driving environment, it effectively assesses the controller’s ability to reduce energy consumption for platooning vehicles.</div></div>

Truck platoons are expected to improve safety and reduce fuel consumption. However, their use is projected to accelerate pavement damage due to channelized-load application (lack of wander) and potentially reduced duration between truck-loading applications (reduced rest period). The effect of wander on pavement damage is well documented, while relatively few studies are available on the effect of rest period on pavement permanent deformation. Therefore, the main objective of this study was to quantify the impact of rest period theoretically, using a numerical method, and experimentally, using laboratory testing. A 3-D finite-element (FE) pavement model was developed and run to quantify the effect of rest period. Strain recovery and accumulation were predicted by fitting Gaussian mixture models to the strain values computed from the FE model. The effect of rest period was found to be insignificant for truck spacing greater than 10 ft. An experimental program was conducted, and several asphalt concrete (AC) mixes were considered at various stress levels, temperatures, and rest periods. Test results showed that AC deformation increased with rest period, irrespective of AC-mix type, stress level, and/or temperature. This observation was attributed to a well-documented hardening–relaxation mechanism, which occurs during AC plastic deformation. Hence, experimental and FE-model results are conflicting due to modeling AC as a viscoelastic and the difference in the loading mechanism. A shift model was developed by extending the time–temperature superposition concept to incorporate rest period, using the experimental data. The shift factors were used to compute the equivalent number of cycles for various platoon scenarios (truck spacings or rest period). The shift model was implemented in AASHTOware pavement mechanic–empirical design (PMED) guidelines for the calculation of rutting using equivalent number of cycles.