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This volume contains the proceedings of the SUMO Conference 2017 which was held from 8th to 10th May 2017 with a focus on autonomous mobility. In the current transition process traffic simulation is the only tool which can give us insights in the mechanisms of traffic in largely automatized traffic scenarios. SUMO as an open source tool provides a wide range of traffic planning and simulation functionalities to support the scientific community. The conference proceedings offer an overview of the applicability of the SUMO tool suite as well as its universal extensibility due to the availability of the source code. The major topic of this fifth edition of the SUMO conference is the calibration of simulation to real world or handbook data as well as communicating networks of intelligent vehicles. A number of contributions cover heterogeneous traffic networks, junction control and new traffic model extensions to the simulation. Subsequent specialized issues such as emission modelling and personal rapid transit simulation are targeted as well. At the conference the international user community exchanged their experiences in using SUMO. With this volume we provide an insight to these experiences as inspiration for further projects with the SUMO suite.

Dear reader, You are holding in your hands a volume of the series „Reports of the DLR-Institute of Transportation Systems“. We are publishing in this series fascinating, scientific topics from the Institute of Transportation Systems of the German Aerospace Center (Deutsches Zentrum für Luft- und Raumfahrt e.V. - DLR) and from his environment. We are providing libraries with a part of the circulation. Outstanding scientific contributions and dissertations are here published as well as projects reports and proceedings of conferences in our house with different contributors from science, economy and politics. With this series we are pursuing the objective to enable a broad access to scientific works and results. We are using the series as well as to promote practically young researchers by the publication of the dissertation of our staff and external doctoral candidates, too. Publications are important milestones on the academic career path. With the series „Reports of the DLR-Institute of Transportation Systems / Berichte aus dem DLR-Institut für Verkehrssystem¬technik“ we are widening the spectrum of possible publications with a bulding block. Beyond that we understand the communication of our scientific fields of research as a contribution to the national and international research landscape in the fiels of automotive, railway systems and traffic management. This volume contains the proceedings of the SUMO2014 – Modeling Mobility with Open Data, which was held from 15th to 16th May 2014 in Berlin-Adlershof, Germany. SUMO is a well established microscopic traffic simulation suite which has been available since 2002 and provides a wide range of traffic planning and simulation tools. The conference proceedings give a good overview of the applicability and usefulness of simulation tools like SUMO ranging from new methods in traffic control and vehicular communication to the simulation of complete cities. Another aspect of the tool suite, its universal extensibility due to the availability of the source code, is reflected in contributions covering parallelization and interfacing improvements to govern microscopic traffic simulation results. The major topic of this second edition of the SUMO conference is open data. Several articles cover the acquisition and refinement of traffic networks as one of the fundamental data sources. Subsequent specialized issues such as data models for emissions and Bluetooth simulation are targeted as well. The conference’s aim was bringing together the large international user community and exchanging experience in using SUMO, while presenting results or solutions obtained using the software or modeling mobility with open data. Let you inspire to try your next project with the SUMO suite. There are many new applications in your environment. Prof. Dr.-Ing. Karsten Lemmer

When choosing between an off-street or an on-street facility, cyclists consider different factors, among which the most important are safety – or better, perceived risk – and travel speed. The presence of an off-street facility clearly encourages bicycle modal choice, but in case of inconsistency, poor design or a significant pedestrian flow, the user can consider reduced the off-street path’s utility. The present study’s objective was to investigate the correspondence between cyclists’ travel speed and the disturbance due to the presence of other facility users both on a shared off-street path and on a shared on-street lane. Three segments of the cycle network in the city of Bologna were examined, evaluating their percentages of usage and the statistical distribution of cyclists’ speeds. Furthermore, separated measures were made in order to evaluate the decrease of speed caused by the different disturbances that a cyclist can encounter on an off-street path (other cyclists and pedestrians) and on an on-street lane (motor vehicles). Decreased speed and probability of disturbance were thus used to determine a weighted average cyclists’ speed in the two situations, to be compared with the ideal speeds. The results suggest that the bigger disturbance on an off-street path is constituted by pedestrians, and a high pedestrian volume on the facility could induce cyclists to choose to move on the street, even considering the higher risk when sharing the cross section with motor vehicles.

This paper describes a methodologic and procedural framework for performing quantitative vulnerability analysis of a road network. Following advanced as well as consolidated approaches adopted by various well known transport scientists, road transport network vulnerability is interpreted as a variable that is directly related to link importance. Network simulation methods and software tools are proposed for estimating link flows and network cost differentials, under the quite sophisticated assumptions of Deterministic User Equilibrium instead of simply interpreting link costs to be constant with respect to link flows. Traffic counts are cheap data which are also suggested to be taken into consideration for both determining link vulnerability ranks and to surrogate possible lack of information regarding transport demand, which could be compensated, in total absence of data, by the application of proper gravitational models.

The main findings are that a vast majority of the population is not attached to the car, but ready to change to PT, if its service includes direct and seated transport – these are hardly characteristics satisfiable with conventional collective transport. Instead, radical technological innovations such as PRT have the potential to satisfy all characteristics required to trigger a significant mode-shift to a sustainable public transport mode.

The current study investigates how employing traffic counters at best to count bike flows. In particular, this paper illustrates the main characteristics of traffic counters, discussing their advantages and shortfalls, and where they have to be located in order to minimize vehicular and pedestrian interferences when counting bike flows. Instruments were placed in 20 sections, for 7 days. Data were collected continuously. The choice of the particular type of counter, either radar or pneumatic, was performed by taking into account both geometrical and operational variables such as bicycle lane width, type of transport mode allowed, and proximity to roads with high traffic volumes. In addition to instrumental bike flow monitoring, a manual monitoring was conducted in each section. Operators’ reports indicate the instant in which bike cross the monitored section, the direction, and the number of cyclists riding outside the bicycle paths. Manual monitoring is useful to compare data, to determine the level of use of cycle tracks, to calibrate instruments and evaluate their precision. Instrumental data consist of numerical strings containing date, time, direction, speed and number of reflection points, which indicate vehicle size. During the instrumental monitoring phase, a first calibration was performed, determining a range of reflection points corresponding to each class of vehicle. In this way we could distinguish between pedestrian, bicycles, scooters, and cars. Secondly, instrumental data were compared with manual data referred to the same time interval in order to improve the results obtained in the first calibration step. Indeed, under the assumption that the error associated to manual data is lower with respect to the instrumental data one, the number of events recorded by instruments is similar to the number of events recorded by operators. In our case, the error regarding instrumental counts was about 10%. For the specific case of radar traffic counters, the number of reflection points changes according to the direction of travel, due to the value of tilt angle, measured with reference to roadway axis. Then, the collected data were introduced in templates, that allowed drawing bar-graphs with the number of bikes every 15-minute interval, during every day of measurement. By processing these data, we obtained daily flows, weekday and holiday average flows, medium frequency, peak hour factor, level of use, peak periods, climatic dependence and other information. The methodology applied in this research is easy to use and can be adapted to the specific goal of the study that will be performed in order to individuate critical situations and possible interventions.

In this paper, the results of a research regarding the transit network of the city of Bologna are presented in order to highlight those factors affecting the reliability of a transit service at high frequency. In literature, several authors relate bus service reliability to the variability of travel time performance (Polus, 1978; Sterman and Schofer, 1976); others with the adherence to schedules (Bates et al., 2001), others to the maintenance of the designed service frequency (Janos and Furth, 2002), others with the waiting time at the bus stops (Bowman and Turnquist, 1981), and others to the impossibility of getting on the bus because of capacity issues (Chapman, 1976). Anyway, the reliability of a transit service is a key element both for users - real and potential ones - and providers. Low service reliability implies the reduction of the service quality perceived by users causing an increase of the amount of time passengers must wait at a bus stop as well as the comfort reduction due to vehicles’ overcrowding (Bates et al., 2001; Rietvield et al., 2001; TCRP, 1999; Prioni and Hensher, 2000; Welding, 1957; Turnquist, 1978). From providers perspective, low service reliability means a reduction of the veh-km delivered and an inefficient utilization of the fleet: some buses travels full of passengers whereas others are empty. This implies the need of additional vehicles to be provided, thus increasing the operating costs. Moreover, as reliability decrease, public transport demand will decrease too thus engendering a lower income for the service provider. The reliability is strictly related to the bunching phenomenon. Bus bunching refers to a group of two or more transit vehicles scheduled to be evenly spaced along the same route, which run in the same location at the same time. This occurs when at least one of the vehicles is unable to keep its schedule because of the interaction with other vehicles of the traffic steam, presence of signalized intersections along the route, demand increase, etc., which implies a bus to be early/late with respect to the planned schedule. Theoretically, the driver should try to adjust the bus speed in relation to the gap with the preceding bus; although it represents one of the most important hypothesis of bunching simulation models, this procedure, which requires driver knows the position of the preceding vehicles, is not usually adopted (Nagatani, 2001). This research provides a general analysis based on reliability, identifying and discussing its determinants. The relative importance of each determinant is analyzed through a survey conducted along two of the main bus routes of the Bologna transit network. This analysis could allow providers identifying appropriate strategies, preventive or corrective ones, in order to improve the service reliability.

Si stima che i costi esterni (inquinamento atmosferico ed acustico, incidentalità, climate change) prodotti da sistemi di trasporto stradali siano superiori al 3% circa del prodotto interno lordo. Tra le misure che si stanno adottando in ambito urbano per limitare l’entità di questi costi, anche in considerazione della crisi economica di questi anni e dell’aumento dei prezzi dei carburanti, oltre allo sviluppo di sistemi ITS (information technology system) e di sistemi innovativi di trasporto (Personal Rapid Transport), vi sono interventi finalizzati a promuovere la diffusione della mobilità ciclabile anche per spostamenti medio-lunghi. Una fase fondamentale nell’ambito della pianificazione di una rete ciclabile è quella rappresentata dal monitoraggio dei flussi: tale fase consente di individuare le criticità della rete nell’attuale scenario e successivamente di verificare gli effetti attesi conseguenti a determinati interventi (analisi before and after). In questo studio viene presentata una metodologia di monitoraggio dei flussi: vengono in particolare illustrati i principali risultati di alcune campagne di indagini condotte negli ultimi anni sulle principali piste ciclabili del Comune di Bologna, evidenziando le caratteristiche fondamentali degli strumenti utilizzati anche in relazione alle interferenze con le altre componenti della mobilità (pedonali e veicolari). La metodologia impiegata per il monitoraggio dei flussi sulla rete ciclabile di Bologna è applicabile a qualsiasi altro contesto urbano.