Enhanced Traffic Management Procedures of Connected and Autonomous Vehicles in Transition Areas

In light of the increasing trend towards vehicle connectivity and automation, there will be areas and situations on the roads where high automation can be granted, and others where it is not allowed or not possible. These are termed ‘Transition Areas’. Without proper traffic management, such areas may lead to vehicles issuing take-over requests (TORs), which in turn can trigger transitions of control (ToCs), or even minimum-risk manoeuvres (MRMs). In this respect, the TransAID Horizon 2020 project develops and demonstrates traffic management procedures and protocols to enable smooth coexistence of automated, connected, andconventional vehicles, with the goal of avoiding ToCs and MRMs, or at least postponing/accommodating them. Our simulations confirmed that proper traffic management, taking the traffic mix into account, can prevent drops in traffic efficiency, which in turn leads to a more performant, safer, and cleaner traffic system, when taking the capabilities of connected and autonomous vehicles into account

Cooperative Automated Driving for managing Transition Areas and the Operational Design Domain (ODD)

When cooperative automated vehicles (CAVs) emerge on urban roads, there will be areas and situations where all levels of automation can be granted, and others where highly automated driving will not be allowed or is not feasible. Complex environments or temporary road configurations are examples of situations leading to takeover requests and are referred to as 'Transition Areas'. Such situations are assumed to cause negative impacts on traffic safety and efficiency, in particular with mixed traffic fleets. The TransAID project is developing a digital infrastructure and dedicated traffic management strategies to assist CAVs at transition areas, and preserve safe and smooth traffic flow. This paper explains the relevance of transition areas and the link to the operational design domain (ODD) of automated vehicles. By combining results from different projects with findings from stakeholder consultation workshops, ODD is discussed in detail and a conceptual structure to guide the discussion is provided

TransAID Deliverable D2.1: Use cases and safety and efficiency metrics

The main objective of this Deliverable 2.1 is to describe and identify the use cases where disruptions of traffic flow are expected to be most severe because of transitions between automation levels, and to identify KPIs to evaluate those use cases. For those identifications, a state of the art literature review has been conducted, a workshop was held with road authority stakeholders, advisory board members have been consulted and experts have been interviewed. The findings have been combined to identify the relevant aspects for TransAID scenarios and Transition of Control (ToC) in general. The large number of aspects (or dimensions) affecting automated vehicle behaviour and possible trigger conditions in combination with the many uncertainties regarding those aspects and conditions (e.g. what exactly triggers a ToC or Minimum Risk Manoeuvre?), posed a challenge for the use case and scenario definitions. Through brainstorming using a template based on above mentioned aspects and conditions, TransAID has identified five generic services that can be applied to many situations. Because of their generic characteristic, these services are expected to mitigate negative impacts resulting from vehicles in Transition Areas, regardless of the uncertainties (i.e. even if certain conditions are different, the solutions still apply). As a result, an overview was created of example situations where transition of control occurs regularly and causes traffic flow disruptions. By means of detailed services and use case descriptions, the deliverable gives a comprehensive overview on (negative) traffic safety and traffic efficiency impacts, for both urban, inter-urban and motorway situations, and proposes a preliminary set of (high-level) traffic measures

TransAID Deliverable 5.4: Signalling for informing conventional vehicles

A smooth introduction of automated vehicles in mixed traffic environments requires a mutual understanding between, and cooperation of, the different entities - being automated, connected or simply legacy vehicles. This is especially true when looking at transition areas, where automated vehicles reach their limits and transitions of control happen frequently, leading to new impacts on traffic efficiency and safety. As shown in D4.2, it is important to address this impact by providing infrastructure advice to automated vehicles. In addition, to achieve a mutual understanding, it is not less important to also inform unequipped vehicles about the issues which are coming up. This deliverable identifies communication requirements to legacy vehicles, esp. by giving information about reasons of appearing situations, consequences and measures for avoiding negative impacts. Several existing technologies are introduced and their effectiveness in terms of the communication requirements is analysed. On this basis, the TransAID approach is defined. Here, a mixture of Variable Message Signs (VMS), static signage and an external HMI of CAVs is in focus. To also bridge to a more individual advice, also a web-service approach using mobile devices in the vehicles is included and presented in this deliverable. All approaches in this deliverable need to be treated as prototypes, as neither the HMI has been tested nor any international study has been performed yet. Nevertheless, it is very important to start this discussion now, as it is of key societal interest to avoid negative impacts when automated vehicles enter the road

Infrastructure-Assisted Automated Driving in Transition Areas

This chapter investigates TA scenarios and performs simulations. In order to start the simulations, several preparatory steps were made. At first, scenarios had to be defined. As capabilities of future AVs are difficult to foresee and as the problem has several dimensions, it has been decided to use service definitions (i.e. the kind of possible infrastructure influences) as the main criterion for clustering the dimensions. Five services have been proposed and converted into five scenarios. In order to perform baseline simulations of the five scenarios, vehicle models had to be chosen and even newly developed, so that simulation of AVs and the TOC became possible. The models needed to be parametrized according to estimations of future traffic shares, future number of TOR, TOC, and MRM. This chapter highlights the measured effects in one of the studied scenarios. It also explains how simulations get more sophisticated and realistic by using the iTETRIS-integrated platform for traffic simulation, communication, and TM. Furthermore, the plans for performing real-world feasibility assessments including V2X message set definitions have been introduced, closing this first report

TransAID Deliverable 5.2: V2X-based cooperative sensing and driving in Transition Areas

The objective of the TransAID (Transition Areas for Infrastructure-Assisted Driving) project is to deal with situations that cooperative and automated vehicles (CAV) might face when they are approaching to traffic conditions or zones that their automated systems are not able to handle by themselves. In those cases, the driver will be required to take control of the vehicle; this is the socalled Transition of Control (ToC). TransAID develops and demonstrates traffic management procedures and protocols to increase the overall traffic safety and efficiency specially at transition areas (i.e. zones where ToCs should take place) considering the coexistence of CAVs, autonomous vehicles (AVs), cooperative vehicles (CVs) and legacy vehicles (LV). TransAID measures require the use of communications between vehicles (V2V), and between vehicles and the road infrastructure (V2I) which are mainly used to gather information about the traffic stream through cooperative sensing and to support in the coordination of the vehicles maneuvers through cooperative maneuvers. In this context, this document shows the sensor devices and techniques to fuse their data that are being developed in TransAID. This includes techniques implemented at camera-equipped infrastructures that are able to detect, create bounding boxes and uniquely track objects using optical flow, and at the vehicle employing a hybrid sensor fusion strategy which contains a low-level LIDAR fusion module, that transforms the sensor data of multiple laser scanners into a common coordinate system, and an object-level fusion module, that fuses in-vehicle sensor data with data coming from neighbouring vehicles. The document also shows the cooperative techniques that are being designed to enable the Collective Perception Service (CPS) in line with ETSI. The ETSI's CPS entails the continuous exchange of Collective Perception Messages (CPM) that include a logic representation of the objects detected by the sensors and which are useful to improve the vehicles' and the infrastructure's perception of the driving environment. A key aspect for the efficient execution of the CPS is the definition of appropriate generation rules for the transmission of the CPMs, i.e. how often they are transmitted and what information do they include. This document includes a comprehensive analysis of the effect on the communications performance and information awareness of different CPM generation rules that are being considered in ETSI. In particular, the CPM generation rules follow a periodic policy (at 10Hz or 2Hz) where all detected objects are included, or a dynamic one where only the objects fulfilling some requirements are included. The conducted analysis has shown that there is a trade-off between perception capabilities and communications performance/scalability: vehicles detecting the same object(s) and including them in their CPMs create redundant detection which can help improve the perception capabilities but generate higher channel load levels and therefore impact the performance of V2X networks. The obtained results show that the ETSI's dynamic generation policy significantly reduces the communications channel load compared with the periodic ones, without compromising the perception capabilities. In the framework of TransAID, advanced policies will be proposed to further optimize the CPM, both its content and transmission triggering conditions, in order to achieve the necessary levels of redundancy and minimize the impact of the implementation of CPM in the stability and scalability of future V2X networks. In addition, this document investigates existing cooperative driving mechanisms, and specially the ETSI approach on manoeuvre coordination. The ETSI's Manoeuvre Coordination Service (MCS) is defining new concepts and messages which can be used to coordinate manoeuvres between vehicles. TransAID is actively participating in this process, e.g., by means of the definition of the Manoeuvre Coordination Message (MCM) and extending the role of the infrastructure to support the vehicles' manoeuvres coordination under certain scenarios and conditions. In this context, this document presents the message flow for the set of services that are being considered in TransAID. First, this document has analysed the traffic management measures defined by the different services of the TransAID project, and the required message flow for each service has been defined. Each message flow describes how, when, and where the vehicles communicate between them, and between them and the infrastructure, to execute the traffic management measures. Then, this document provides a preliminary analysis of the MCM generation rules. As highlighted for the CPMs, MCM messages should be transmitted with a frequency high enough to guarantee that the vehicles' manoeuvre coordination is possible. However, a too frequent exchange of MCM messages can increase the channel load to the point that it can negatively impact the performance and scalability of the V2X network. The conducted analysis has shown the importance of considering the vehicular context for the generation of the MCM messages in order to achieve a good balance between channel load and reliability for a safe execution of the cooperative manoeuvres

TransAID Deliverable 9.5: TransAID Final Conference

The TransAID (Transition Areas for Infrastructure-Assisted Driving) project focuses on development and demonstration of infrastructure-assisted traffic management procedures, protocols, and guidelines for smooth coexistence between automated, connected, and conventional vehicles especially at Transition Areas. Main objectives are: - Evaluation and modelling of current automation prototypes and the behaviour of the drivers. - Assessment of the impact of Transition Areas on traffic safety and efficiency. Generate requirements on enhanced traffic management procedures. - Development of infrastructure-assisted management procedures and protocols to control connected, automated, and conventional vehicles at Transition Areas. - Definition of V2X message sets and communication protocols for the cooperation between connected/automated vehicles and the road infrastructure. - Development of procedures to enhance the detection of conventional vehicles and obstacles on the roads and to inform/influence conventional vehicles. - Integration, testing, and evaluation of the TransAID infrastructure-assisted traffic management protocols and procedures in a simulation environment. Validation and demonstration of them by means of real-world prototypes at test sites. - Provision of a guideline/roadmap to stakeholders regarding the requirements on traffic infrastructure and traffic management in order to cope with Transition Areas considering mixed traffic. This Deliverable describes the organisation and main outcome of the TransAID Final Conference. The event was first planned on 1 July 2020 (one full day), in conjunction with IEEE (Institute of Electrical and Electronics Engineers) FISTS (Forum on Integrated and Sustainable Transportation System) on 30 June to 2 July in Delft, The Netherlands. A Call for Papers was published, and a Special Session on cooperative and automated driving in a transition phase (dedicated for TransAID) was arranged with scientific papers, and invited speakers without papers. Experts in the domain of cooperative and automated driving outside the consortium and public at large were invited. Various dissemination materials were prepared, and promotion activities were conducted. In addition, a demonstration with automated vehicles (from DLR) on a section of public road in the campus of Delft University of Technology was under preparation. Due to COVID-19, the format of the Final Conference was changed. The demonstration had to be cancelled, and the event was held online on 1-2 July 2020 with a different programme by changing moderator and invited speakers. The online event had around 49-63 participants. On Day-1, the Project Officer Georgios Sarros (EC INEA) gave an opening speech. After a brief project introduction given by Julian Schindler (DLR - Project Coordinator), some TransAID partners presented the main technical results of the project, such as modelling and impact assessment of automated vehicles, traffic management procedures for transition areas, connectivity and signalling, and system integration and evaluation approach. Between each presentation a survey was conducted to get the view of the participants on some specific subjects in the domain and to make the online event interactive. During the break, some project videos were shown (which have been published on the project website). The Day-2 online workshop targeted city participants and non-technical issues. The results are detailed in TransAID Deliverable D8.1 Stakeholder consultation report. In general, the final conference was successful, and achieved the main goals. However, an online event could not be as interactive as face-to-face, and there were no effective networking opportunities for participants. The TransAID consortium planned to have demonstration activities in November, but unfortunately both had to be cancelled in the last moment due to the worsened COVID-19 situation. Instead, a video has been prepared

TransAID Deliverable 8.1: Stakeholder consultation report (final version)

The TransAID project defines, develops and evaluates traffic management measures based on C-ITS equipped road infrastructure to eliminate or mitigate the negative effects of Transition of Control (ToC) along Transition Areas in future mixed traffic scenarios where automated, cooperative, and conventional vehicles will coexist. This document summarises the results of the stakeholder consultation activities of the TransAID project. For TransAID, the most relevant stakeholders are transport authorities and policy makers, road operators, vehicle manufacturers and suppliers, road infrastructure and traffic service providers, academia and knowledge institutes, future product owners and standardisation bodies. The consultation activities aimed to gather feedbacks on the project choices (selected use cases, scenarios, modelling solutions, implementation approaches) as well as on the achieved results. Such feedbacks were necessary to confirm the validity of the project's work, and to adapt, whenever possible and needed, its implementation while running. Consultation also allowed obtaining the stakeholders' view on the impact of prospective automated vehicles introduction. Finally, the stakeholders were asked about their ambitions and interests related to role and responsibilities in future scenarios of automated vehicle presence. Hearing about these last two aspects was necessary to identify possible activities beyond the TransAID project's duration. A summary of 9 stakeholder consultation events is provided in this deliverable: Main stakeholder workshops - TransAID-MAVEN-CoExist Stakeholder workshop, 10 October 2017, Brussels - TransAID-INFRAMIX stakeholder workshop, 9 October 2019, Graz - TransAID final event, stakeholder workshop, 2 July 2020, online International liaison activities - TransAID-U.S. CAMP expert meeting, 25 July 2019, Detroit - TransAID + ITS Japan / UtmobI expert meeting, 7-8 April 2020, online Additional stakeholder consultation opportunities - TransAID session and survey, 8 June 2019, IEEE-IV, Paris - EU EIP workshop on ODD, 1 October 2019, Turin - International workshop on ODD, 22 October 2019, Singapore - Joint dissemination of H2020, CEDR projects and other initiatives related to CAVs and Infrastructure, 3 March 2020, Brussels For each stakeholder consultation event, this deliverable gives a detailed description of the scope and aim, participants, plenary and break-out sessions, survey results (when applicable) and implications to the TransAID work. The main common findings that have been identified throughout the various events are listed in the following along with the major implications for TransAID and/or any similar follow-up activity: - Managing mixed traffic in transition areas is still an almost unexplored field. Despite transition areas are recognized as a prospective problem, very little is known or has been studied about it. This simple acknowledgment confirms the need and timeliness of TransAID. - Due to the uncertainty about many technical aspects related to the introduction of AD, it was difficult for transport authorities and traffic managers to provide insights on aspects to be considered for the selection of TransAID use cases and scenarios. Nevertheless, the majority of use cases and scenarios finally selected by TransAID were recognized to be reasonably generic, yet addressing recurrent problems, and hence deemed useful for real-world application. - Connectivity was recognized as a key enabler to extend the Operational Design Domain (ODD) of AD. In this sense, most experts foresee application of hybrid solutions with both ITS-G5 and cellular connectivity capabilities. For this purpose, TransAID's assumption of digitalizing the road infrastructure with additional sensing, computing and communication capabilities was acknowledged to be correct, even if maybe not realisable in the short term. - TransAID traffic management allowing the road infrastructure to provide additional information to CAVs was also recognized as a valid approach in almost all the consultation and twinning events. In this context, European and Japanese stakeholders firmly defend the use of infrastructure support for automated driving and even highlight the need to adapt traffic rules for automation or change the legal frameworks (e.g. authorize the road infrastructure to provide advices that break the traffic rules if needed). On the contrary, US stakeholders are very hesitant and fear possible financial consequences resulting from liability issues. - Remote operation is an emerging possible solution at least for management of level 4 automated public transport (e.g. autonomous shuttles or pods) in edge cases and transition areas, when the vehicles operate without a steward in the vehicle. This use case is not considered by TransAID, and hence it would be interesting to investigate its effectiveness with similar evaluations means as those utilized by TransAID. - Sensitivity of information around OEMs' current and future implementations has prevented obtaining commonly recognized functional descriptions reusable for modelling and simulations of automated vehicles behaviours. Despite that, the modelling solutions developed in the project under the consultancy of Hyundai were considered adequate and meaningful by the inquired stakeholders. - For the TransAID measures to work effectively, vehicle AD capabilities shall be known by the infrastructure, and infrastructure (support) capabilities shall be known by OEMs. Consequently, sharing this data in both directions is needed. From the consultation, this approach was welcomed by infrastructure stakeholders while OEMs were more hesitant mostly due to competition and liability implications arising from sensitivity of the shared information. To preserve sensitivity of information, the TransAID "intermediary service" concept (see TransAID D4.3) was generally supported, but its practical application in real-world deployment scenarios would need to be proven. - In addition, it is considered needed to derive clear and unambiguous definitions of AD ODDs for adoption at both OEMs and infrastructure side. Transport Authorities could use this information for allowing vehicles of different automation capabilities to use specific roads or to provide additional physical of digital support where needed. Nevertheless, defining ODDs is a complex task for the involved stakeholders, and despite initial activities have been started and proposals have been made, there is still a long way to go. - From an even more generic perspective, transport authorities (especially cities) are mostly interested in fulfilling their greener, safer and comfort goals and see AD as an opportunity in that direction. For the moment being, they are not favouring a particular automated transport mode in a proactive way. Rather, they seem to be monitoring the situation to apply reactive policies when AD introduction will be more mature and clearer. In fact, adoption of alternative policies like strategically "managing" private CAVs vs. fostering use of MaaS with public automated shuttles will depend on penetration. For TransAID, it is irrelevant which way authorities will choose, as the proposed TransAID solutions can apply irrespectively of the selected automated transport mode. As it can be seen, some of the findings from the consultation events reflect the uncertainty associated to vehicle automation and its evolution in the coming decades. Nevertheless, from the sequence of stakeholder consultation events a steady progression in the collective understanding of the relation between vehicle automation and infrastructure could be observed. The possible implications to the stakeholders involved became also clearer at subsequent events

TransAID Deliverable 2.2: Scenario definitions and modelling requirements

In D2.1 five services have been described encompassing multiple use cases and scenarios. In this Deliverable 2.2, 5 scenarios are selected, one for each service, and worked out in more detail. The detailed timelines of the scenarios are provided describing what exactly is the sequence of events in the scenario and what the effect of the measures, which being developed in WP4, should be. Also, the simulation networks for each of the scenarios have been created and their specification is documented in this deliverable. Furthermore, the requirements for the simulations have been specified, ranging from several vehicle (type) models to the traffic composition, demand and vehicle mixes. For the second iteration of the project, 5 new or extended scenarios have been selected based on findings from the first iteration. Those findings are also used to update the overall simulation requirements and parameters (i.e. definition of actors, traffic composition, demand and vehicle/driver models). Finally, based on insights from the first iteration, several questions have been formulated which will be used during several surveys (e.g. digital polls or paper surveys during events; interviews with experts). The goal is to gain insights into legal implications, (expected) driver and/or automated vehicle behaviour and infrastructure specific aspects with respect to automated vehicles

Enhanced Traffic Management Procedures in Transition Areas

In light of the increasing trend towards vehicle connectivity and automation, there will be areas and situations on the roads where high automation can be granted, and others where it is not allowed or not possible. These are termed "Transition Areas". Without proper traffic management, such areas may lead to vehicles issuing take-over requests (TORs), which in turn can trigger transitions of control (ToCs), or even minimum-risk manoeuvres (MRMs). In this respect, the TransAID Horizon 2020 project develops and demonstrates traffic management procedures and protocols to enable smooth coexistence of automated, connected, and conventional vehicles, with the goal of avoiding ToCs and MRMs, or at least postponing/accommodating them. Our baseline simulations confirmed that a coordinated distribution of takeover events can prevent a drop in traffic efficiency, which in turn leads to a more performant, safer, and cleaner traffic system, when taking the capabilities of connected and autonomous vehicles into account