61 research outputs found

    The Use of Lane-Centering to Ensure the Visible Light Communication Connectivity for a Platoon of Autonomous Vehicles

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    International audienceThe new emerging Visible Light Communication (VLC) technology has been subjected to intensive investigation, evaluation, and lately, deployed in the context of convoy-based applications for Intelligent Transportations Systems (ITS). The technology limitations were defined and supported by different solution proposals to enhance the crucial alignment and mobility limitations. In this paper, we propose to incorporate VLC technology and the Lane-Centering (LC) technique to ensure the VLC-connectivity by keeping the autonomous vehicle aligned to the lane center using vision-based lane detection in a convoy-based formation. As soon as the road lanes are detectable, the evaluated system showed stable behavior independently of the inter-vehicle distances and without the need to exchange information between vehicles. Such a combination can ensure the optical communication connectivity with a lateral error of less than 30 cm. The evaluation of the proposed system is verified using VLC prototype and an empirical result of an LC active application over 60 km on the Madrid M40 highway

    Strategic and Tactical Guidance for the Connected and Autonomous Vehicle Future

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    Autonomous vehicle (AV) and Connected vehicle (CV) technologies are rapidly maturing and the timeline for their wider deployment is currently uncertain. These technologies are expected to have a number of significant societal benefits: traffic safety, improved mobility, improved road efficiency, reduced cost of congestion, reduced energy use, and reduced fuel emissions. State and local transportation agencies need to understand what this means for them and what they need to do now and in the next few years to prepare for the AV/CV future. In this context, the objectives of this research are as follows: Synthesize the existing state of practice and how other state agencies are addressing the pending transition to AV/CV environment Estimate the impacts of AV/CV environment within the context of (a) traffic operations—impact of headway distribution and traffic signal coordination; (b) traffic control devices; (c) roadway safety in terms of intersection crashes Provide a strategic roadmap for INDOT in preparing for and responding to potential issues This research is divided into two parts. The first part is a synthesis study of existing state of practice in the AV/CV context by conducting an extensive literature review and interviews with other transportation agencies. Based on this, we develop a roadmap for INDOT and similar agencies clearly delineating how they should invest in AV/CV technologies in the short, medium, and long term. The second part assesses the impacts of AV/CVs on mobility and safety via modeling in microsimulation software Vissim

    Effects of autonomous vehicles on pavement distress & road safety and pavement distress optimization

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    The commercial application of automation technology in passenger and freight transport will bring positive revolutionary changes in transportation mobility. Despite having more advantages, automation in trucking technology has some detrimental effects on the performance of asphalt pavement and highway safety. This study focuses on optimization of asphalt pavement distresses and prediction of rutting induced traffic safety factors for movement of autonomous trucks. This study optimizes the asphalt concrete (AC) pavement distresses by devising traffic input in Mechanistic-Empirical Pavement Design Software, AASHTOWare. An increase in pavement distresses was observed for a small increase in the standard deviation of wheel wander, uniform distribution of truck traffic loading, and equal distribution of vehicle positioning on the road lanes. Permanent deformation of the asphalt concrete layer for roads (PEDRO) model was incorporated to predict AC pavement rutting for a typical pavement section. Hydroplaning speed and skid resistance as traffic safety factors were evaluated from widely accepted empirical equations for the induced rutting. A standard tire rather than a truck tire was considered due to its high susceptibility to traffic safety. A graphical relationship has been proposed to obtain a design threshold value for hydroplaning speed, water film depth and autonomous truck speed. An attempt was made to improve pavement performance by increasing frequency of truck load in low-temperature period of a day

    Secure Harmonized Speed Under Byzantine Faults for Autonomous Vehicle Platoons Using Blockchain Technology

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    Autonomous Vehicle (AV) platooning holds the promise of safer and more efficient road transportation. By coordinating the movements of a group of vehicles, platooning offers benefits such as reduced energy consumption, lower emissions, and improved traffic flow. However, the realization of these advantages hinges on the ability of platooning vehicles to reach a consensus and maintain secure, cooperative behavior. Byzantine behavior [1,2], characterized by vehicles transmitting incorrect or conflicting information, threatens the integrity of platoon coordination. Vehicles within the platoon share vital data such as position, speed, and other relevant information to optimize their operation, ensuring safe and efficient driving. However, Byzantine behavior in AV platoons presents a critical challenge by disrupting coordinated operations. Consequently, the malicious transmission of conflicting information can lead to safety compromises, traffic disruptions, energy inefficiency, loss of trust, chain reactions of faults, and legal complexities [3,4]. In this light, this thesis delves into the challenges posed by Byzantine behavior within platoons and presents a robust solution using ConsenCar; a blockchain-based protocol for AV platoons which aims to address Byzantine faults in order to maintain reliable and secure platoon operations. Recognizing the complex obstacles presented by Byzantine faults in these critical real-time systems, this research exploits the potential of blockchain technology to establish Byzantine Fault Tolerance (BFT) through Vehicle-to-Vehicle (V2V) communications over a Vehicular Ad hoc NETwork (VANET). The operational procedure of ConsenCar involves several stages, including proposal validation, decision-making, and eliminating faulty vehicles. In instances such as speed harmonization, the decentralized network framework enables vehicles to exchange messages to ultimately agree on a harmonized speed that maximizes safety and efficiency. Notably, ConsenCar is designed to detect and isolate vehicles displaying Byzantine behavior, ensuring that their actions do not compromise the integrity of decision-making. Consequently, ConsenCar results in a robust assurance that all non-faulty vehicles converge on unanimous decisions. By testing ConsenCar on the speed harmonization operation, simulation results indicate that under the presence of Byzantine behavior, the protocol successfully detects and eliminates faulty vehicles, provided that more than two-thirds of the vehicles are non-faulty. This allows non-faulty vehicles to achieve secure harmonized speed and maintain safe platoon operations. As such, the protocol generalizes to secure other platooning operations, including splitting and merging, intersection negotiation, lane-changing, and others. The implications of this research are significant for the future of AV platooning, as it establishes BFT to enhance the safety, efficiency, and reliability of AV transportation, therefore paving the way for improved security and cooperative road ecosystems

    How Locals Need to Prepare for the Future of V2V/V2I Connected Vehicles

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    Connected and Automated Vehicles (CAVs) are expected to affect the foundations of transportation operations and roadway maintenance as they become more prevalent on the roadways. This report is an effort to address this complex subject for the various owners, agencies and stakeholders involved in traffic operations. It discusses the connected vehicle ecosystem and its background, potential CAV applications, types of communication and hardware required for CAV systems, and recommendations to local road owners. The report also includes a survey sent to local road owners to assess the current readiness of the transportation system for CAVs. Although it is too early to give specific recommendations, general guidance is provided for road owners to begin preparing for the future of CAVs

    Review of Automated Vehicle Technology: Policy and Implementation Implications; Version 1.0; RB28-015, 2016

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    This report provides recommendations for the state of Iowa over the next five years in regards to automated vehicle policy development. These administrative, planning, legal, and community strategy recommendations for government agencies include: • Encouraging automation by preparing government agencies, infrastructure, leveraging procurement, and advocating for safety mandates • Adjusting long range planning processes by identifying and incorporating a wide range of new automation scenarios • Beginning to analyze and, as necessary, clarify existing law as it apples to automated driving • Auditing existing law • Enforcing existing laws • Ensuring vehicle owners and operators bear the true cost of driving • Embracing flexibility by giving agencies the statutory authority to achieve regulatory goals through different means, allowing them to make small-scale exemptions to statutory regimes and clarifying their enforcement discretion • Thinking locally and preparing publicly • Sharing the steps being taken to promote (as well as to anticipate and regulate) automated driving • Instituting public education about automated vehicle technologies

    Communications par Lumière Visible et Radio pour la Conduite Coopéraive Autonome: application à la conduite en convois.

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    By realizing both low-cost implementationand dual functionality, VLC has becomean outstanding intriguing supportivetechnology by using the vehicular existedinfrastructure.This thesis aims to contribute to theautonomous vehicular communicationand urban mobility improvements. Thework addresses the main radio-basedV2V communication limitations and challengesfor ITS hard-safety applicationsand intends to deploy the vehicular lightingsystem as a supportive communicationsolution for platooning of IVCenabledautonomous vehicles. The ultimateobjectives of this Ph.D. researchare to integrate the VLC system withinthe existing C-ITS architecture by developinga VLC prototype, together withsufficient hand-over algorithms enablingVLC, RF, and perception-based solutionsin order to ensure the maximumsafety requirements and the continuousinformation exchange between vehicles.The feasibility and efficiency of thesystem implementation and hand-overalgorithms were subjects to deep investigationsusing computer simulators andtest-bed that considers applications ofautomated driving. In addition to the improvementin road capacity when platoonformations are used. The carried outsimulations followed-up by experimentalresults proved that the integration of VLCwith the existed RF solutions lead to adefinite benefit in the communicationchannel quality and safety requirementsof a platooning system when a properhand-over algorithm is used.La communication par lumière visibleVLC est devenue une technologie attractivevu qu’elle assure une implémentationà faible coût et une doublefonctionnalité. En effet, elle permetd’utiliser l’infrastructure déjà existantesur le véhicule à savoir les lampesd’arrière et frontales comme des unitésde transmission. Cette thèse s’intéresseà rendre plus efficace les communicationsdes véhicules autonomes ainsi quela gestion de la mobilité urbaine. Nousnous intéressons tout d’abord aux principaleslimitations des communicationsradio sans fil dans le contexte des applicationsde sécurité routière à hautes exigences.Nous nous concentrons ensuiteau déploiement d’un système d’éclairagesur les véhicules dans le but de fournir unmoyen de communication de soutien auxcommunications radio pour l’applicationde peloton. L’objectif primordial decette thèse est d’intégrer la technologieVLC dans l’architecture de communicationITS en implémentant un prototypede communication VLC et en concevantde nouveaux algorithmes de handoverpermettant une transition transparenteentre différents moyens de communicationinter-véhiculaires (VLC, communicationsans fil et techniques de perception).Le but est d’assurer les exigencesde sécurité requises par les applicationset l’échange continue de l’informationentre véhicules. L’efficacité de ces algorithmesa été validée à travers de nombreusessimulations et test-bed réels aucours desquels nous avons considérél’application de conduite automatisée.Ces différentes méthodes de validationont démontré que l’intégration de la technologieVLC avec les solutions de communicationsradio permet d’améliorer laqualité du canal de transmission ainsique la satisfaction des exigences de sécuritérelatives à l’application de peloton

    Assessing the Safety and Operational Benefits of Connected and Automated Vehicles: Application on Different Roadways, Weather, and Traffic Conditions

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    Connected and automated vehicle (CAV) technologies have recently drawn an increasing attention from governments, vehicle manufacturers, and researchers. Connected vehicle (CV) technologies provide real-time information about the surrounding traffic condition (i.e., position, speed, acceleration) and the traffic management center\u27s decisions. The CV technologies improve the safety by increasing driver situational awareness and reducing crashes through vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I). Vehicle platooning with CV technologies is another key element of the future transportation systems which helps to simultaneously enhance traffic operations and safety. CV technologies can also further increase the efficiency and reliability of automated vehicles (AV) by collecting real-time traffic information through V2V and V2I. However, the market penetration rate (MPR) of CAVs and the higher level of automation might not be fully available in the foreseeable future. Hence, it is worthwhile to study the safety benefits of CAV technologies under different MPRs and lower level of automation. None of the studies focused on both traffic safety and operational benefits for these technologies including different roadway, traffic, and weather conditions. In this study, the effectiveness of CAV technologies (i.e., CV /AV/CAV/CV platooning) were evaluated in different roadway, traffic, and weather conditions. To be more specific, the impact of CVs in reduced visibility condition, longitudinal safety evaluation of CV platooning in the managed lane, lower level of AVs in arterial roadway, and the optimal MPRs of CAVs for both peak and off-peak period are analyzed using simulation techniques. Currently, CAV fleet data are not easily obtainable which is one of the primary reasons to deploy the simulation techniques in this study to evaluate the impacts of CAVs in the roadway. The car following, lane changing, and the platooning behavior of the CAV technologies were modeled in the C++ programming language by considering realistic car following and lane changing models in PTV VISSIM. Surrogate safety assessment techniques were considered to evaluate the safety effectiveness of these CAV technologies, while the average travel time, average speed, and average delay were evaluated as traffic operational measures. Several statistical tests (i.e., Two sample t-test, ANOVA) and the modelling techniques (Tobit, Negative binomial, and Logistic regression) were conducted to evaluate the CAV effectiveness with different MPRs over the baseline scenario. The statistical tests and modeling results suggested that the higher the MPR of CAVs implemented, the higher were the safety and mobility benefits achieved for different roadways (i.e., freeway, expressway, arterials, managed lane), weather (i.e., clear, foggy), and traffic conditions (i.e., peak and off-peak period). Interestingly, from the safety and operation perspective, at least 30% and 20% MPR were needed to achieve both the safety and operational benefits of peak and off-peak period, respectively. This dissertation has major implications for improving transportation infrastructure by recommending optimal MPR of CAVs to achieve balanced mobility and safety benefits considering varying roadway, traffic, and weather condition

    Automation, Electrification, and Shared Mobility in Freight

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    Caltrans 65A0674 Task Order 009USDOT Grant 69A3551747109Understanding the potential benefits and unintended consequences of automation and electrification revolutions in freight is challenging for academics, practitioners, and decision-makers. On one hand, these revolutions could help mitigate the disproportionate impacts of freight transportation on externalities and improve efficiency; on the other hand, they could generate additional issues such as right-of-way conflicts, crashes, and traffic incidents. To shed light on these issues, this report conducts an extensive review of the state-of-the-practice of such innovations for both long-haul and last-mile freight distribution. The study concentrates on the potential barriers, challenges, and opportunities of the different innovations, and discusses the market readiness of some of the technologies. Finally, the authors discuss planning considerations for the advent and widespread use of these innovations, and provide research and policy considerations
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