Complexity in modern vehicles consists of an increasingly large multitude of components that operate together. While functional verification of individual components is important, it is also important to test systems of interacting components within a driving environment, both from a functional perspective and from a driver perspective. One proven way for testing is vehicle simulators and in this work the main goals have been to increase flexibility and scalability by introducing a distributed driving simulator platform. 

A distributed simulation architecture was designed and implemented, based on user needs defined in a previous project, which divides a driving simulator environment into four major entities with well-defined interfaces. These entities are Session Control, Environment Simulator, Driving Simulator and Vehicle simulator. High Level Architecture (HLA) Evolved, an IEEE standard, was chosen as the standard for communication. HLA Evolved is based on a publish-subscribe architecture, and is commonly used for distributed simulations. The entities and the communication topology are described in detail in the report.

The evaluation of the distributed simulation architecture focused on flexibility and scalability, and on timing performance. Results show that the implemented distributed simulation architecture compared to the non-modified architecture increased flexibility and scalability, as several distributed setups were tested successfully. However, it also has an inherent communication latency due to packaging and sending of data between entities, which was estimated to be one millisecond. This is an effect which needs to be considered for a distributed simulation. Especially if the communication between the Driving Simulator and the Vehicle Simulator is sensitive to such delays. During evaluations of the distributed simulation architecture, the Driving Simulator and the Vehicle Simulator were always located at one site in a low latency configuration.

In an attempt to increse the freight transport capacity in Sweden, introduction of longer and heavier trains is investigated. To aid this investigation, a freight train simulator was designed and constructed. Here, the implemented freight train dynamics model is described, which includes slip control, a modular wagon model structrue and pneumatic brake system. Further, stable real-time performance of the implemented dynamics model is discussed.

Moving base driving simulators, with an enclosed human driver, are often used to study driver-vehicle interaction or driver behaviour. Reliable results from such a driving simulator study strongly depend on the perceived realism by the driver in the performed driving task. Assuring sufficient fidelity for a vehicle dynamics model during a driving task is currently to a large degree a manual task. Focus here is to automate this process by employing a framework using collected driving data for detection of model quality for different driving tasks. Using this framework, a powertrain model credibility is predicted and assessed. Results show that chosen powertrain model is accurate enough for a driving scenario on rural roads/motorway, but need improvements for city driving. This was expected, considering the complexity of the vehicle dynamics model, and it was accurately captured by the proposed framework which includes real-time information to the simulator operator.

Allowing higher speeds for freight trains would provide opportunities for a higher prioritization in the traffic flow by rail traffic management, which in itself is a capacity gain and should generate better flows and higher capacity on the Swedish rail network, especially on the major railways. Simulators are an effective and safe way to investigate the effects of changes in both driver behavior and capacity.

The purpose of this project was to create capacity-enhancing opportunities and actions by developing a freight train simulator and investigating its possible application areas. The aim of the project was to provide a freight train simulator, consisting of a locomotive and a number of wagons, which can be used in studies to increase capacity through, for example, optimized speed, and thus changing braking profiles, for long trains. The project has delivered knowledge of new test methods, a freight train simulator and a software platform for further testing.

The project was conducted in three successive stages. In the first phase, a pilot study was carried out with drivers, operators and problem owners, who gave the researchers an understanding of the driving environment. In addition, some of the data needed for the development of the freight train simulator was collected. In the second phase, a freight train (software and hardware) model was developed. Stage three was a validation study together with drivers.

A Traxx model driver console was purchased from a German manufacturer. The vehicle model was developed from a single unit, Regina type (motorcar train), into a combination of several units. The train in the simulator consists of one or more locomotives and a number of wagons with a total length of up to 750 meters. A locomotive of Traxx model is used. For each device, locomotive and wagon, data is required: length, weight, load, brake, roll and air resistance. In addition, information about noise, driving, braking (re-electrical braking and conventional pneumatic brake) (P-brake), cab equipment and more are added. Currently, the track between Falköping - Jönköping - Forserum is modelled and will be used for ATC trains. The model is configurable using combinations of a locomotive (Traxx) and, currently, four different types of wagons. These can be linked in different combinations.

Some applications that were discussed at the start of the project were, on the one side, those that could naturally be linked to longer and heavier trains, and, on the other, the ideas that arose because of the equipment purchased. At the Transport Administration winter meeting, a workshop was conducted where further uses were discussed. Among these are applications within education, energy efficient driving or design. Education and certain types of studies could be performed with the existing locomotive model, while others require either validation of parameters or some further development of the model.

The project has provided knowledge of new test methods, this research report and a product in the form of a freight train simulator and software platform for further testing. The project has also delivered a national resource of simulator software. The software provides for cost-effective testing activities in the freight train domain. A freight train simulator has been developed, which will be valuable as a demonstration tool as well as a platform for training,

The aim of the project was to develop a method to assess if individuals with visual field loss can drive in a safe manner. The starting point for the project was that the method should be a simulator based method because essentially two criteria were desirable. First, it was important that several events occurred systematically and that events were possible to evaluate, i.e., that it was possible to discriminate between good and bad performances. Second, these events should be the same events for all individuals that was to be tested. The aim was to develop a method that optimizes the validity and reliability with respect to testing of each and one of unique individuals. The testing procedure of the individual level was important because the method would not be used for research purposes but primarily to determine whether a unique individual with visual field loss can drive in a safe manner. Several details that can go wrong during an ordinary experiment, when running subjects, have a minimal impact concerning the experiment because it is most often possible to complement the experimental data collection with another subject. This is not an option for this project.

These criteria and points raised above collectively resulted in the method developed. When an individual completed the scenario developed, a test protocol was generated (after a lot of work). This protocol reveals how the individual performed during the 37 (+2) events (and related measures) based on a safety margin perspective. To support the rater with the assessment of a subject a) data from a reference group (over 100 individuals) and b) a developed test protocol (with critical thresholds for different measurements) were used. The assessment was carried out by two independent raters. If the raters agreed no further judgments were performed. If the raters disagreed a third rater assessed the subjects’ performance. The purpose of the test protocol is that those individuals who want to use the test protocol results as a basis for an exemption application, can do so. It is still the Transport Agency, which decides on an exemption cases.

The study in this publication investigates the need and potential for night-time scenarios in driving simulators, determines how such night-time scenarios could be reproduced and identifies the objects most important to reproduce. Although on average 12 out of every 24 hours are dark and considering that most situations are more demanding for drivers in dark conditions, simulations of driving scenarios with different degrees of darkness are not common. The project work comprised a pre-study that involved an investigation of the need and potential of night-time scenarios with the help of input from different stakeholders, consolidation of what is known up to now through benchmarking and state of the art, and a review of available technical solutions. The objective was to identify pros and cons with existing solutions and aspects that are important to consider in order to reproduce the most important components in realistic night-time scenarios. Based on the results, six important use cases were identified and two of these (‘Driver fatigue’ and ‘Objects without light sources’) were studied in more detail. It was concluded that for night-time scenarios there is enough darkness in general in the simulator environment. The question is whether it is possible to create sufficient contrast for objects that are meant to be observable. For daytime scenarios, the light levels in the simulator are clearly unrealistically low and this limitation might even trigger unwanted sleepiness.

Future vehicles are expected to be equipped with wireless communication technology, that enables them to be “connected” to each others and road infrastructures. Complementing current autonomous vehicles and automated driving systems, the wireless communication allows the vehicles to interact, cooperate, and be aware of its surroundings beyond their own sensors’ range. Such sys- tems are often referred to as Cooperative Intelligent Transport Systems (C-ITS), which aims to provide extra safety, efficiency, and sustainability to transporta- tion systems. Several C-ITS applications are under development and will require thorough testing and evaluation before their deployment in the real-world. C- ITS depend on several sub-systems, which increase their complexity, and makes them difficult to evaluate.

Simulations are often used to evaluate many different automotive applications, including C-ITS. Although they have been used extensively, simulation tools dedicated to determine all aspects of C-ITS are rare, especially human factors aspects, which are often ignored. The majority of the simulation tools for C-ITS rely heavily on different combinations of network and traffic simulators. The human factors issues have been covered in only a few C-ITS simulation tools, that involve a driving simulator. Therefore, in this thesis, a C-ITS simulation framework that combines driving, network, and traffic simulators is presented. The simulation framework is able to evaluate C-ITS applications from three perspectives; a) human driver; b) wireless communication; and c) traffic systems.

Cooperative Adaptive Cruise Control (CACC) and its applications are chosen as the first set of C-ITS functions to be evaluated. Example scenarios from CACC and platoon merging applications are presented, and used as test cases for the simulation framework, as well as to elaborate potential usages of it. Moreover, approaches, results, and challenges from composing the simulation framework are presented and discussed. The results shows the usefulness of the proposed simulation framework.

Simulation is often used as a technique to test and evaluate systems, as it provides a cost-efficient and safe alternative for testing and evaluation. A combination of simulators can be used to create high-fidelity and realistic test scenarios, especially when the systems-under-test are complex. An example of such complex systems is Cooperative Intelligent Transport Systems (C-ITS), which include many actors that are connected to each other via wireless communication in order to interact and cooperate. The majority of the actors in the systems are vehicles equipped with wireless communication modules, which can range from fully autonomous vehicles to manually driven vehicles. In order to test and evaluate C-ITS, this paper presents a distributed simulation framework that consists of (a) a moving base driving simulator; (b) a real-time vehicle simulator; and (c) network and traffic simulators. We present our approach for connecting and co-simulating the simulators. We report on limitation and performance that this simulation framework can achieve. Lastly, we discuss potential benefits and feasibility of using the simulation framework for testing of C-ITS.

This paper is an experience report of team Halmstad from the participation in a competition organised by the i-GAME project, the Grand Cooperative Driving Challenge 2016. The competition was held in Helmond, The Netherlands, during the last weekend of May 2016. We give an overview of our car's control and communication system that was developed for the competition following the requirements and specifications of the i-GAME project. In particular, we describe our implementation of cooperative adaptive cruise control, our solution to the communication and logging requirements, as well as the high level decision making support. For the actual competition we did not manage to completely reach all of the goals set out by the organizers as well as ourselves. However, this did not prevent us from outperforming the competition. Moreover, the competition allowed us to collect data for further evaluation of our solutions to cooperative driving. Thus, we discuss what we believe were the strong points of our system, and discuss postcompetition evaluation of the developments that were not fully integrated into our system during competition time.

Cooperative adaptive cruise control (CACC) is a cooperative intelligent transport systems (C-ITS) function, which especially when used in platooning applications, possess many expected benefits including efficient road space utilization and reduced fuel consumption. Cut-in manoeuvres in platoons can potentially reduce those benefits, and are not desired from a safety point of view. Unfortunately, in realistic traffic scenarios, cut-in manoeuvres can be expected, especially from non-connected vehicles. In this paper two different controllers for platooning are explored, aiming at maintaining the safety of the platoon while a vehicle is cutting in from the adjacent lane. A realistic scenario, where a human driver performs the cut-in manoeuvre is used to demonstrate the effectiveness of the controllers. Safety analysis of CACC controllers using time to collision (TTC) under such situation is presented. The analysis using TTC indicate that, although potential risks are always high in CACC applications such as platooning due to the small inter-vehicular distances, dangerous TTC (TTC < 6 seconds) is not frequent. Future research directions are also discussed along with the results.

In the near future, Cooperative Intelligent Transport System (C-ITS) applications are expected to be deployed. To support this, simulation is often used to design and evaluate the applications during the early development phases. Simulations of C-ITS scenarios often assume a fleet of homogeneous vehicles within the transportation system. In contrast, once C-ITS is deployed, the traffic scenarios will consist of a mixture of connected and non-connected vehicles, which, in addition, can be driven manually or automatically. Such mixed cases are rarely analysed, especially those where manually driven vehicles are involved. Therefore, this paper presents a C-ITS simulation framework, which incorporates a manually driven car through a driving simulator interacting with a traffic simulator, and a communication simulator, which together enable modelling and analysis of C-ITS applications and scenarios. Furthermore, example usages in the scenarios, where a manually driven vehicle cut-in to a platoon of Cooperative Adaptive Cruise Control (CACC) equipped vehicles are presented.

Connected and automated driving in the context of cooperative intelligent transport systems (C-ITS) is an emerging area in transport systems research. Interaction and cooperation between actors in transport systems are now enabled by the connectivity by means of vehicle-to-vehicle and vehicle-to-infrastructure (V2X) communication. To ensure the goals of C-ITS, which are safer and more efficient transport systems, testing and evaluation are required before deployment of C-ITS applications. Therefore, this paper presents a simulation framework-consisting of driving-, traffic-, and network-simulators-for testing and evaluation of C-ITS applications. Examples of cooperative adaptive cruise control (CACC) applications are presented, and are used as test cases for the simulation framework as well as to elaborate on potential use cases of it. Challenges from combining the simulators into one framework, and limitations are reported and discussed. Finally, the paper concludes with future development directions, and applications of the simulation framework in testing and evaluation of C-ITS.

For a few decades, driving simulators have been supporting research and development of advanced driver assistance systems (ADAS). In the near future, connected vehicles are expected to be deployed. Driving simulators will need to support evaluation of cooperative driving applications within cooperative intelligent transportation systems (C-ITS) scenarios. C-ITS utilize vehicle-to-vehicle and vehicle-to-infrastructure (V2X) communication. Simulation of the inter vehicle communication is often not supported in driving simulators. On the other hand, previous efforts have been made to connect network simulators and traffic simulators, to perform C-ITS simulations. Nevertheless, interactions between actors in the system is an essential aspect of C-ITS. Driving simulators can provide the opportunity to study interactions and reactions of human drivers to the system. This paper present simulation of a C-ITS scenario using a combination of driving, network, and traffic simulators. The architecture of the solution and important challenges of the integration are presented. A scenario from Grand Cooperative Driving Challenge (GCDC) 2016 is implemented in the simulator as an example use case. Lastly, potential usages and future developments are discussed.

Vehicles in cooperative intelligent transport systems (C-ITS) often need to interact with each other in order to achieve their goals, safe and efficient transport services. Since human drivers are still expected to be involved in C-ITS, driving simulators are appropriate tools for evaluation of the C-ITS functions. However, driving simulators often simplify the interactions or influences from the ego vehicle on the traffic. Moreover, they normally do not support vehicle-to-vehicle and vehicle-to-infrastructure (V2X) communication, which is the main enabler for C-ITS. Therefore, to increase the C-ITS evaluation capability, a solution on how to extend a driving simulator with traffic and network simulators to handle cooperative systems is presented as a result of this paper. Evaluation of the result using two use cases is presented. And, the observed limitations and challenges of the solution are reported and discussed.

At early market penetration, automated vehicles will share the road with legacy vehicles. For a safe transportation system, automated vehicle controllers therefore need to estimate the behavior of the legacy vehicles. However, mismatches between the estimated and real human behaviors can lead to inefficient control inputs, and even collisions in the worst case. In this paper, we propose a framework for evaluating the impact of model mismatch by interfacing a controller under test with a driving simulator. As a proof- of-concept, an algorithm based on Model Predictive Control (MPC) is evaluated in a braking scenario. We show how model mismatch between estimated and real human behavior can lead to a decrease in avoided collisions by almost 46%, and an increase in discomfort by almost 91%. Model mismatch is therefore non-negligible and the proposed framework is a unique method to evaluate them.

The forces in the couplings of articulated vehicle combinations, propel and fully determine the path of any towed unit thus playing a significant role in the vehicle behavior. A failure in the coupling could potentially have a devastating effect if it occurs while driving in traffic. To prevent this from happening, states and road authorities impose requirements in terms of tolerated forces on any coupling selection. The current legal requirement framework is based on an ISO standard, that stipulates minimum force levels that the couplings should stand. These forces have been derived under semi-empirical assumptions for a set of five vehicle combinations. The present report aims to extend the coupling requirements to two vehicle combinations that are candidates to become legal on the public road network. Due to the semi-empirical nature of the ISO standard, validation needed to be performed. The here presented requirements for the two new combinations were validated against simulation models and checked for reasonable requirements for some example weights of the combinations. The proposed requirements are aligned with the existing requirements derived from the ISO standard. This implies that they could be used to form the legal requirements on these vehicle combinations. However, further investigations on well-grounded deduced requirements should be performed to secure safety margins.

VDTestS set out to probe the potential of a driving simulator in the field of vehicle dynamics testing. For this purpose, a simulator test case was prepared embodying the nature of a vehicle dynamics test set-up. The goal was to figure out if the drivers in the simulator could identify the handling differences owed to changes in vehicle settings, while driving simulated trucks.

A truck model was validated against the performance of a real vehicle under a predefined set of manoeuvres. This was coupled with the tuning of the simulator motion to improve the perception of the vehicle dynamics. These efforts were followed by definition of a group of four test cases, each corresponding to a set of alternate vehicle properties. These sets were selected based on their potential impact on the vehicle handling and correlation with changes that could occur in a real vehicle. Finally, experiments were conducted in VTI’s motion-based driving simulator, Sim IV in Gothenburg, with participation of ten engineers and mechanics from VGTT product development well familiar with truck mechanics and truck driving. The set-up made it possible to gather feedback, about the suitability of the driving simulator in these testing conditions, from professionals in the field. Data was collected subjectively via interviews and questionnaires as well as objectively from the logs comprising of driver inputs and vehicle motions generated during the simulator drives.

Projektet har syftat till att visa på möjligheterna för att göra studier av fotgängarbeteende genom att nyttja modern Virtual Reality-teknik. Under projektets gång har en VR-studio byggts upp på VTIs kontor i Linköping. Till denna miljö har det utvecklats mjukvara som kan användas för att studera beteendet hos fotgängare i tänkta trafiksituationer. Simulatorn är utrustad med blickmätningssystem vilket gör att det går att både mäta och interaktivt visualisera var användaren har sin uppmärksamhet i varje ögonblick. Det går att uppleva vad användaren ser i den virtuella världen ur både ett förstapersons- och tredjepersonsperspektiv. Det finns ett särskilt läge för Mixed Reality, det vill säga ett läge där en verklig videoström kombineras med den datorgenererade omgivningen. För att visa nyttan med simulatorn så har ett scenario utvecklats. I detta scenario kan en användare uppleva hur det är att interagera med olika fordon, både självkörande och andra.

This publication is a review of available technologies for tracking the user in virtual reality systems. Tracking the user location is important for generating views that adapts to the user’s movements.

This review begins with the basic terms used in virtual reality in general. Followed by the important characteristics for tracking equipment. This is followed by a chapter on the fundamental algorithms used for position calculations. Then the most common technologies with their advantages and disadvantages are presented. The text conclude with how these technologies are used in automotive virtual reality.

Head mounted displays (HMDs) is an emerging technology and the availability of affordable systems is growing fast. Replacing projector and large screen solutions with head mounted displays may appear as an appealing solution. However, inherent properties and technical limitations of these systems need to be understood and considered before making the leap to virtual reality.

This paper outlines some of the most fundamental limitations of head mounted displays relevant to this context, both from a technical and human factors perspective. Desirable properties of scenarios and types of studies are deduced, based on these limitations. Finally, a meta analysis is performed on the feasibility of transferring simulator studies found in the literature to platforms with head mounted displays. The results suggest that a noticeable amount (40%) of the investigated simulator studies could likely have been performed with head mounted displays. This number could be increased further with technical advances in display resolution, display technology, reduction in latency, etc.

This paper presents a comparative study of driving behavior when using different virtual reality modes. Test subjects were exposed to mixed, virtual, and real reality using a head mounted display capable of video see-through, while performing a simple driving task. The driving behavior was quantified in steering and acceleration/deceleration activities, divided into local and global components. There was a distinct effect of wearing a head mounted display, which affected all measured variables. Results show that average speed was the most significant difference between mixed and virtual reality, while the steering behavior was consistent between modes. All subjects but one were able to successfully complete the driving task, suggesting that virtual driving could be a potential complement to driving simulators.

This paper presents a comparative study of driving behavior when using different virtual reality modes. Test subjects were exposed to mixed, virtual, and real reality using a head mounted display capable of video see-through, while performing a simple driving task. The driving behavior was quantified in steering and acceleration/deceleration activities, divided into local and global components. There was a distinct effect of wearing a head mounted display, which affected all measured variables. Results show that average speed was the most significant difference between mixed and virtual reality, while the steering behavior was consistent between modes. All subjects but one were able to successfully complete the driving task, suggesting that virtual driving could be a potential complement to driving simulators.

Using mixed reality in vehicles provides a potential alternative to using driving simulators when studying driver-vehicle inter- action. However, virtual reality systems introduce latency in the visual system that may alter driving behavior, which, in turn, results in questionable validity. Previous studies have mainly focused on visual latency as a separate phenomenon. In this work, latency is studied from a task-dependent viewpoint to investigate how participants’ driving behavior changed with increased latency. In this study, the investigation was performed through experiments in which regular drivers were subjected to different levels of visual latency while performing a simple slalom driving task. The drivers’ performances were recorded and evaluated in both lateral and longitudinal directions along with self-assessment questionnaires regarding task performance and difficulty. All participants managed to complete the driving tasks successfully, even under high latency conditions, but were clearly affected by the increased visual latency. The results suggest that drivers compensate for longer latencies by steering more and increasing the safety margins but without reducing their speed.

Performance-based standards (PBS) is a regulation policy to address the complexity of variations in vehicle combinations. It enables a direct way of addressing certain requirements associated with the safety, environment and road network and their implications to the vehicle specific quantities without stipulating vehicle properties.

Computer-based simulations may be an efficient tool to assess the performance measures. However, using simulations through models in a legislation raise questions of model accuracy and model complexity. What is a required level of modelling details to be used to assess a PBS measure?

We investigate three level of complexity of models and the impact this have on three longitudinal performance measures; Startability, Gradeablity and Acceleration Capability. Simulations for 10 vehicle combinations are compared with two different engine alternatives. For Nordic countries, slippery road conditions are common during winter conditions. Hence, low friction is included in the comparison.

The comparison suggested that the complexity could potentially be kept really low, without major loss of accuracy. However, for slippery conditions, a higher levels of complexity might be required.

New electric power trains can be subject to different failures when compared to those arising in conventional vehicles. The objectives for active safety investigations within the EVERSAFE project were to address vehicle stability under these failure conditions and the driver response to relevant types of failures. Failure conditions that affect the vehicle stability are believed to be significantly different from today’s conventional internal combustion engine cars, and may potentially be a substantial safety problem if not treated in a correct manner. To study these effects, two examples of system failures and their consequences on the driver response and vehicle stability were investigated with the help of three studies.

The first two studies investigated a failure of wheel hub motors (WHMs), an emerging technology among the future generation of electric vehicles (EV). The main benefits of a WHM are its controllability, high efficiency, high power density and low weight. However, the direct connection to the wheel comes along with the potential disadvantage in case a failure occurs in the system.

The third study conducted within the active safety focus of the EVERSAFE project examined a failure of the regenerative braking (RB) system. The latter is a system designed to convert kinetic energy to chemical energy stored in the energy storage system (i.e. battery) while the vehicle decelerates.

Single vehicle accidents are commonly caused by fatigue and distraction and resulting in severe casualties and high economic costs. In order to evaluate driver recovery from run-off-road accidents, comprising of 80% of fatal crashes on rural roads, a simulator study in an advanced full-motion driving simulator was carried out. Drivers were given a secondary task to perform at six positions down the road (to simulate distraction), and an artificial yaw deviation was added to the vehicle to induce a run-off-road accident whilst the driver was distracted. The results show that the severity of the recovery manoeuvre was larger than similar events caused by the failure of automated lane keeping systems, leading to lane departures. Furthermore, significant learning effects was found, providing recommendations for further studies into run-off-road experiments.

Denna studie har mätt väggrepp på våt, saltad asfaltväg vid temperaturer kring noll grader för slitna och nya vinterdäck i syfte att undersöka hur väggreppet för de tre olika förekommande typerna av vinterdäck i Sverige försämras med ålder och slitage. Även sommardäck har ingått i studien. Totalt har 84 däck testats, varav 31 helt nya däck och 53 begagnade. Resultaten visar att dubbdäck och nordiska odubbade vinterdäck presterar likvärdigt på detta underlag. Skillnaden mellan nya och slitna däck av dessa två typer är för de flesta undersökta prestandamått i praktiken obefintlig. De nya europeiska däcken presterar cirka 10–13 procent bättre än nya dubbdäck och nordiska odubbade vinterdäck på den våta asfalten vid det aktuella väderförhållandet. För de slitna däcken är prestandaövertaget för de europeiska däcken mindre, cirka 5–7 procent bättre än de andra två typerna av vinterdäck. Sommardäcken presterar i princip likvärdigt eller bättre än de europeiska vinterdäcken, både som nya och slitna.

This work presents a comprehensive study of the performance of winter tires on snow, ice, and asphalt. A set of 77 different winter tires were carefully selected for the study. Of these, 27 were new and 50 were worn from real traffic use. All three tire types for winter conditions (Nordic, European, and studded) were represented. All tires have been tested using a mobile tire-testing device for snow and asphalt and using a stationary tire-testing facility for ice. Both devices recorded the tire forces and motions, enabling a close to complete stationary characterization of the tires. In addition, 42 of the tires were tested on a passenger car, where brake performance was evaluated for the three different road conditions. This enables a comparative study of performance between tire types and wear for various winter road conditions. The results suggest that the recorded data represent real vehicle performance. Some conclusions from the measurements are that the effect of wear is consistent between the tire groups and that the performance degradation is most noticeable on studded tires on ice and on European tires on snow.

The main focus of this study was to develop a software able to link eye tracking data to simulator data, making it possible to automatically detect what the driver is looking at in the simulated world. This was achieved by merging data from a SmartEye system with data from the simulator. Thereby realtime visualisation of where the driver is looking is facilitated, and what the driver is targeting can be shown to the test leader to trigger events in the scenarios, etc. This also facilitates automatic gaze annotations that can be used in subsequent analyses when studying visual behaviour.

The developed software, VIMSI, is responsible for collecting eye tracking data from SmartEye, filter and aggregate this data with data from the simulation and then send processed data to the graphics to visualize the result. The software was tested in one of VTI’s driving simulators. This initial testing of VIMSI showed that the software is capable of visualising what the driver is looking at in real time. The software also makes it possible to log data from the test drives which can be useful when studying driver behaviour. To improve the functionality of VIMSI, it is necessary to consider using UDP instead of IPC when directing data from the VIMSI software to the graphics engine VISIR. This will enable the use of another software, ScenarioReplay, developed at VTI for replaying test drives. A proper configuration and calibration of the SmartEye cameras is necessary to achieve high quality of the data from the SmartEye Pro software, which is a precondition for VIMSI.

This article investigates the potential of a motion based driving simulator in assessing and comparing dynamic performance of different heavy vehicles. A driving simulator study with 55 professional truck drivers is performed and the achieved results show a strong correlation between the objective and subjective measures of the different vehicles performance. The motion based driving simulator is used to compare the performance and controllability of high capacity transport vehicles with conventional heavy vehicles.

This article investigates the potential of a motion-based driving simulator in the field of vehicle dynamics testing, specifically for heavy vehicles. For this purpose, a case study was prepared embodying the nature of a truck dynamics test setup. The goal was to investigate if the drivers in the simulator could identify the handling differences owed to changes in vehicle parameters, while driving the simulated trucks. Results show that the drivers could clearly identify the differences in vehicle behaviour for most of the performed tests, which motivates further investigative work in this area and exposes the feasibility of heavy vehicle dynamics testing in simulators.

Project “Performance Based Standards for High Capacity Transports in Sweden” started at the end of 2013 to investigate applicability of PBS in Sweden, and ended in Autumn 2017. The purpose of the project was to propose a performance based regulation of HCT vehicles and their access to the road network; under a PBS approach to regulation, standards would specify the performance required from the vehicle, rather than mandating prescriptive length and weight limits. In this project, all the three domains of safety, infrastructure and environment were addressed, but the focus has been on safety for which extensive testing, simulations and analysis were performed. This report gathers the outcomes of the project.

This publication presents a project aiming to develop virtual representations of real roads for use in driving simulators. The development was done in order to enable assessments of new systems on existing and well known roads in a driving simulator, and will increase the external validity of virtual testing. Furthermore, the usage of the virtual model of such roads makes the simulator results better comparable to earlier performed or later following road tests. The roads connecting Göteborg-Borås-Alingsås-Göteborg were selected. The purpose for this is due to their proximity to the vehicle industry in west Sweden and to the test tracks “Hällered” and “AstaZero”. However, the tools and methods developed can be used to build a virtual representation of any other road through a surrounding landscape and/or more urban environment. The project was carried out in steps, starting with data collection (investigation and assessment of available data from different sources as well as measurement of road properties) followed by data treatment (remove irrelevant data and errors, filtering, etc.), modelling (mathematical description of road properties) and simulation (selection of data formats for real time simulation).

By the year 2018, the Climate Act will come into force. By 2030, climate impact in the transport sector should have fallen by 70 percent compared with 2010 and by 2045 Sweden’s climate impact will be net zero. This means a fundamental transformation of the energy supply of vehicles in road transport. For buses in city traffic, electrification is favorable because electric buses are both exhaustfree and quiet, giving a lesser environmental impact in the street environment, and by that the possibility of creating attractive bus lines.

To exemplify how a bus electrification can be done, a driving simulator study was conducted on a possible electric bus line in the city of Lund using an electric road system. The goal of electrification was to achieve a high user acceptance and to meet the targets for the future environment and energy use.

With the help of various sources of information about electric buses, electric road systems and the urban environment of Lund, virtual models were created, which were then installed in the driving simulator.

To evaluate whether the bus and electrification complied with the user acceptance requirements, bus drivers participated in a test in a dynamic driving simulator, SIM II at VTI in Linköping. The results showed that the drivers had no major difficulties in driving the bus so that the electrification worked. Unfortunately, some of the drivers suffered from sickness while driving (“simulator sickness”) and had to stop driving.

An evaluation of the driving simulator used as a tool for public relation purposes was made by providing an information sheet and demonstrating the electrification to employees in Lund municipality by using a small, moveable driving simulator. Interviews about electric buses and electrification were made before and after the demonstration to see effects on the opinion and understanding of electric buses and electric road systems. The results showed that the simulator drive gave added value in addition to the information sheet only, 2/3 of the participants answered that their understanding was increased by the simulator drive and 1/3 answered that it was not changed. The attitude to the electric bus and the electric road system did not change. Most people considered that the simulator could be a helpful tool in decision making.

An analysis of the energy consumption of the bus showed that the battery level was lower at the end of the test drive than in the beginning, i.e. the battery level dropped. This would not have been the case if the electrification had been made more advantageously, and thus would not need to be a limiting factor in future implementation.

In addition, the studied electric road system was compared with some other power supply options such as charging at bus depot and at bus end stop. The pros and cons of these alternatives were discussed based on economic and bus operational perspectives.

Future transportation systems will be a heterogeneous mix of items with varying connectivity and interoperability. A mix of new technologies and legacy systems will co-exist to realize a variety of scenarios involving not only connected cars but also road infrastructures, pedestrians, cyclists, etc. Future transportation systems can be seen as a System of Systems (SoS), where each constituent system - one of the units that compose an SoS - can act as a standalone system, but the cooperation among the constituent systems enables new emerging and promising scenarios. In this paper we investigate how to architect cars so that they can be constituents of future transportation systems. This work is realized in the context of two Swedish projects coordinated by Volvo Cars and involving some universities and research centers in Sweden and many suppliers of the OEM, including Autoliv, Arccore, Combitech, Cybercom, Knowit, Prevas, ÅF-Technology, Semcom, and Qamcom.

Being able to assess your own performance can be vital to maintain safe mobility for older drivers. Overestimation can lead to increased risk of being involved in a crash and underestimation to unjustifiable restrictions in mobility. A pre/post intervention study was conducted with the aim to improve older drivers’ ability to assess their own driving performance. The aim was not to improve performance per se but the ability to assess, i.e. to calibrate themselves. Thus, a driving simulator program was developed and evaluated with a group of 36 older drivers. However, due to simulator sickness only 21 driver completed the study. Drivers repeatedly assessed their driving performance by answering the question “How well do you think you performed on the driving task? (1 = very bad to 5 = very well)”. As a reference of correctly assessed driving performance we used an experienced occupational therapist (specialised in driver assessment) who assessed the drive with the same scale (expert assessment).

Feedback can be an effective tool for change, which we wanted to evaluate. Thus, feedback to the drivers were given as a specification of errors made (e.g. forgot to use direction indicators, driving too fast, etc.). Feedback could also include information on correct behaviour (e.g. give way to pedestrians, keeping the right speed etc.). Thus, the drivers were divided into two groups: one (n=11) who were told of their misses and one (n=10) who were also informed about their correct behaviour. Training was done at three different occasions.

The aim of this project was to develop a lane-change scenario for driving simulators to analyse the characteristics of lane-change manoeuvres performed with heavy vehicles.

The definition of the lane-change scenario was based on a literature review, and an investigation of lane-change accidents in Sweden.

A lane-change manoeuvre is in the literature typically described by accepted gap at the initiation of the manoeuvre as well as duration of the manoeuvre and speed during the manoeuvre. The literature review showed that there is a lack of real-world data regarding lane-change manoeuvres with heavy vehicles. The data that exist are collected mainly in the US and for discretionary lane changes, and a distinction between sizes of heavy vehicles is rarely made. Regarding accidents involving heavy vehicles on European level, there is a general lack of useful and reliable accident data. The most comprehensive data are available from the US and show that lane-change accidents account for a large share of accidents involving heavy vehicles.

The investigation of lane-change accidents was made in the Swedish Traffic Accident Data Acquisition (STRADA), on 10 500 police-reported accidents with heavy vehicles involved during the years 2003 to 2013. In STRADA, lane-change accidents are categorized together with overtaking accidents. Therefore, it is not possible to identify lane-change accidents and their share of heavyvehicle accidents directly from STRADA. Instead, lane-change accidents were identified by reading the accident narratives for overtaking accident and rear-end accidents (in total 5 612 accidents). Rearend accidents were included because the manner of collision may resemble lane-change collisions.

The aim of the present paper was to develop and validate a heavy vehicle dynamics model for driving simulators. The model was thought to be open, with a high level of readability and flexibility for future understanding, modification and use. A stepwise increment of the model complexity was utilized to understand the most contributing factors and to obtain a model capable of running in real-time. The model has been validated objectively using a previously validated model and through subjective evaluation in a driving simulator.

The process of developing new automotive systems includes various testing cycles to assure a save operation in traffic. Physical system testing on test tracks is very important for this purpose, but rather expensive and might only become possible in later stages of the development process. Using a virtual simulation environment offers a safe possibility of testing new systems in early stages of development. Aditionally, driver-in-the-loop tests at test track and in a virtual simulator make it possible to evaluate driver reaction and potential acceptance by the future users of those systems. Within PROSPECT the new functions are investigated under various aspects in several simulator studies and test track studies.

This deliverable D7.3 gives detailed information of conduction and results of the each study. Three studies focus exclusively on the for Vulnerable Road Users (VRUs) specifically dangerous urban intersection scenarios. The first of those studies examines the driver behaviour in a turning situation when a byciclist might be crossing. The second study, which provides an initial step in this line of research, analyzed the acceptance of issued forward collision warning times. In the third study acceptance of an intersection assist autonomous emergency braking systems was tested regarding the acceptance of potential buyers.

Two studies focused on longitudinal scenarios. Both studies followed the same design, but one was conducted on a test track and the other one in a simulator. The main objective was to investigate drivers reactions to FCW warnings and Active Steering interventions in critical VRU scenarios in case of a distraction of the driver.

The Swedish Transport Administration (Trafikverket) has increased the budget for railway operation and maintenance by 47 % for 2018–2029, compared to the previous period. The provision of public transport is increasing as existing lines are expanding and due to the construction of new railway, tram and metro track infrastructure. To ensure the realisation of these infrastructure projects, the railway industry will require a certain amount of competence and resources. The trade organisation, the Swedish Construction Federation (Sveriges Byggindustrier) forecasted a shortage of 1 700 railway workers within track technology, electric technology, signalling technology and tele operations in the coming years, suggesting that the realisation of future infrastructure projects could become challenging.

This report is the second of three deliveries from a research project with the purpose to provide a practical model to forecast the required resources and competences for future railway infrastructure in Sweden. The project is performed by The Swedish National Road and Transport Research Institute (VTI), financed by, and in cooperation with The Swedish Transport Administration. The composition of competence and age for personnel within construction and maintenance of railway infrastructure is depicted in this report. The information and data in this report is basis for the prognosis of competences and resources required in the future. Private agents (railway contractors and consultant companies) and public agents (infrastructure managers for regional and local transportation) in Sweden are included in this study. In addition, railway specific educational programs and courses at upper secondary school, polytechnical- and university levels, currently offered in Sweden are presented.

Severe and fatal accidents between cyclists and motor vehicles are common at intersections, and many involve right-turning vehicles, with drivers not observing an adjacent cyclist. Few structured investigations exist regarding the interaction between the two, and factors to be studied are how infrastructure and vehicle properties affect human decision-making and cycling behaviour. Therefore, a bicycle simulator study was performed, where vehicle type, lane markings and width were systematically varied in a scenario with a cyclist approaching a vehicle from behind at an intersection. 33 participants each cycled through 8 intersections. Data on cycling trajectories, stopping points and speed was coupled with survey data and semantically categorized verbal responses to questions regarding strategy for choice of stopping point. Results show that all three factors (vehicle type, lane markings and available vehicle-adjacent space) significantly affects cyclists’ behaviour (lateral and longitudinal stopping position), speed choice and verbally expressed conscious strategies.

The development within railways is driven by an increased demand for sustainable and punctual transportation. The Swedish transport administration (Trafikverket) anticipates a growth in passenger transport work by 54% until 2040 compared to the levels at 2014. Trafikverket’s National plan for the transport system 2018–2029 describes the most comprehensive effort on railway infrastructure in Swedish modern history. This includes for example parts of the new high-speed track network with a planned total length of 1 500 km. Supplementary to this are the actions planned by other Swedish rail infrastructure managers for public transport. The rail sector has highlighted the need for efforts to strengthen the built-up of knowledge and competence in order to accommodate these future needs. For railway technical engineers the shortage in resources is already pronounced and difficult for the track entrepreneurs to handle. In an investigation by the Swedish construction federation (Sveriges Byggindustrier) the manpower shortage in this profession is estimated to 1 700 persons within a few years’ time.

This report forms the outcome from the first work stage in a research project purposed to develop a practically usable model for prediction of future needs of competence and resources associated with Swedish rail-bound infrastructure. The project is led by the Swedish national road and transport research institute (VTI) with financing from, and in collaboration with, Trafikverket. In their roles as owners of large infrastructure facilities for rail-bound transportation the Stockholm county council, the Traffic office of Gothenburg and the Tramways of Norrköping participate in the reference group of the project. The project outcome is expected to be valuable from several different aspects. Amongst others by offering information to educational institutions in sufficient time in advance in order for them to adjust the syllabus and extent in their long-time planning to meet the market needs. Moreover, the predicted results can constitute important grounds to consider in the strategic policy making both in public and private sectors.

The starting point of prognosis is the infrastructure managers’ long-term budgets, composed of thousands of budgeted measures with planned execution dates. The budgets have been collected from the Swedish Transport Administration, Region Stockholm and Gothenburg office of traffic. By using so-called action category models, each action’s cost is distributed across different segments of the railway industry: infrastructure managers, consultant companies and railway contractors. In (Svanberg et al. 2020) a mapping of personnel with railway specific competence is presented. The data includes 16 railway agents and 58 different professions. The number of persons with railway specific competence amounts to 5 865 persons distributed accordingly: 3 654 persons from railway contractors, 1 377 persons from consultant companies and 834 persons from infrastructure managers.

The prognosis of future personnel need with railway specific competence is presented for the time period 2019‒2025. The total predicted need for personnel with this competence by 2025 is 7 032 persons, which is an increase by 20 % compared to today’s number of personnel. Primarily, personnel at the consultant companies and infrastructure managers are affected by the increased need. The largest gap of personnel during the studied period will affect the railway contractors in year 2021 and amount to 870 persons.

Wheel–rail impact loads and noise at railway crossings are calculated by applying a hybrid prediction model. It combines the simulation of non-linear vertical dynamic vehicle‒track interaction in the time domain and the prediction of sound pressure level using a linear frequency-domain model. The two models are coupled based on the concept of an equivalent roughness spectrum. The time-domain model uses moving Green's functions for the linear vehicle and track models, accounting for wheel structural flexibility and a discretely supported rail with spatially-varying beam properties, and a non-Hertzian wheel–rail contact model. Three-dimensional surface geometry of the wheel and crossing is accounted for in the solution of the wheel–rail contact. The hybrid model is compared against field measurements and is demonstrated by investigating the influence of vehicle speed and crossing geometry on the radiated impact noise. Based on simulation results, it is concluded that the impact loads and noise can be mitigated by reducing the effective dip angle at the crossing, which is determined by the vertical trajectory of the wheel when making the transition between wing rail and crossing nose.