Ecological User Equilibrium in Traffic Management (TM)?

With increasing environmental sustainability awareness significant attention on ecological traffic management (eco-TM) has come into the focus of researchers and practitioners. While different approaches have been applied to reach minimal pollutant production, the classic user equilibrium calculation with the pollutant production as travel costs instead of using travel times remains in the center of attention. However, the validity of such a direct transformation to find a user equilibrium is questionable. In this paper, a simplified analytical approach to examine the above aforementioned validity has been carried out, followed by a simulation approach to verify the results of the analytical approach. The result shows that the pollutant production function violates the usual assumption of a monotonous function (typically, emission has a minimum at travel speeds around 60 km/h). It also indicates that the respective algorithms to compute the user equilibrium must deal with the fact, that the equilibrium solution is not unique and is dependent on the initial solution. This means that substantial modifications to the algorithms that compute the user equilibrium have to be discussed since they do not work as intended when pollutant production is used as travel costs, especially in a transportation system with mixed speeds that cover a range around the minimum emission speed

Dynamic Reroute Modeling for Emergency Evacuation: Case Study of the Brunswick City

The human behaviors during evacuations are quite complex. One of the critical behaviors which affect the efficiency (performance) of evacuation is route choice. Therefore, the respective simulation modeling work needs to function properly. In this paper, SUMO's current dynamic route modeling during evacuation, i.e. the rerouting functions, is examined with a real case study. Four influence factors (1) time to get information, (2) probability to cancel a trip, (3) probability to use navigation equipment and (4) rerouting and information updating period are considered to analyze possible traffic impacts during the evacuation and to examine the rerouting functions in SUMO. Furthermore, some behavioral characters of the case study are analyzed with use of the corresponding detector data and applied in the simulation. The experiment results show that the dynamic route modeling in SUMO can deal with the proposed scenarios properly. Some issues and function needs related to route choice are discussed and further improvements are suggested

Towards safe and efficient shared-space oriented DRT Service – some insights with real case study in Linköping

With the expeditious development in technology autonomous vehicles (AVs) are going to become a part of our daily life. Their possible influences on current transportation systems and the needs of the future traffic systems with the introduction of AVs have been investigated extensively with use of traffic simulation tools. Apart from simulative studies more and more real-life demonstrations of AVs are carried out and real AV data becomes available. The latter one facilitates to further properly model AVs’ driving behaviour in traffic simulation. Related AVs’ impact evaluations can then be more representative and support policy and decision making. In this paper, real autonomous shuttle bus data is analysed to understand driving situation, to derive vehicle-related parameters for enhancing microscopic traffic simulation model, and to find out possible issues in real traffic environment

Developing a Sensor Agnostic Infrastructure-Based Control Approach for Crossroad Assistance using Simulation

Crossroad assistance has the potential to contribute to a fair distribution of road space and increase the safety of all road users. This paper presents an infrastructure-based control approach to support crossroad assistance by implementing remote-controlled turning maneuvers on a test track. The approach involves several steps, including the detection of traffic events using camera- based object recognition, inserting dynamic objects into the simulation via V2X transmission, adding lanes and traffic signal phases through V2X data forwarding to a high-precision simulation map, trajectory prediction of all dynamic objects in the simulation, sending a trajectory list to the test vehicle, and providing feedback through the vehicle’s response to the trajectory list and re-detection of objects

SHOW Deliverable 10.1: Simulation scenarios and tools

This document identifies all simulation tools which are used by all partners participating in Work Package 10 of the SHOW project. Their applications range from vehicle level of shared CCAVs up to mobility level, and they are used to enrich all field experiment results of the SHOW pilots. In addition, a relation of tools to application areas and to SHOW pilots is presented. Furthermore, multiple simulation scenarios are introduced, which define the used tools to evaluate the scenario, their expected results as well as the addressed KPIs from A9.4. After a short presentation of the SHOW sites that are investigated in simulation in this WP, the simulation plans of all participating partners are presented and linked to at least one of the pilot sites. Additionally, data inputs that are required from the SHOW sites are stated

Brunswick simulation scenario for virtual-stops based DRT services with SUMO

This paper presents a general simulation scenario with SUMO of the City of Brunswick, Germany, was set up using traffic network data from OSM and the traffic demand from TAPAS (TAPAS 2017). In this paper the developed simulation scenario is published for other researchers to use and extend. A simulation scenario has been set up and evaluated. The developed scenario includes a simulation of the whole city area of Brunswick. Furthermore, key performance indicators (KPIs) have been chosen to find optimal positions for virtual bus stops for autonomous shuttles. The simulation scenarios give findings of the effect of the position of a virtual bus stop on the traffic flow and the traffic safety. In combination with the walking time to this stop these KPIs give a decision basis for the position of the stop

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

Route choice calibration from multi-point vehicle stream measurements

To better und more precisely assess different transporta-tion design alternatives and traffic management strategies, microscopic traffic simulation models are extensively applied. The respective calibration and validation works are getting more and more important. Nowadays, GPS-based systems are broadly applied. More and more route related information can be collected, which promises great improvements of calibra-tion accuracy. An approach using multi-point vehicle stream measurements is proposed in this paper and is shown to work well in synthetic experiments

SUMO-Cadyts calibration with limited data quality

Traffic simulation has been often used to support decision making in traffic management. Such simulation requires a large amount of fine data which cannot be easily obtained in practice especially when a large network is considered. Under this circumstance, the respective calibration work is challenged. In this study, the route choice calibration of SUMO and Cadyts is applied with a real case study in Hefei, China, to examine (1) to which extent the calibration can achieve and (2) which issues need to be especially taken into account. With the resource limitation the network data is based on the OSM with insufficient quality. Major adjustments are made on the number of lanes, turning lane allocations, speed limitations and traffic signal plans. The last two parts still suffer from the limited data quality. The collected flow data for calibration is also limited for only 15 minutes at five major intersections during different moments in the evening peak hour. The relative absolute error is used as the performance indicator. The results show that the simulation quality is improved with the given limited data and quality, but only to a certain degree, namely the percentage of the investigated links with a flow deviation less than 30% has increased from 38% to 72%. The spectrum of the relative errors has been greatly narrowed after the calibration. Gained experiences related to the application of SUMO-Cadyts calibration are also pointed out as references for further applications