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  • 1.
    Albinsson, Anton
    et al.
    Chalmers Tekniska Högskola.
    Bruzelius, Fredrik
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle. Chalmers Tekniska Högskola.
    Hjort, Mattias
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle.
    Required friction utilization for friction estimation on wet asphalt, an experimental study2018In: The Dynamics of Vehicles on Roads and Tracks, CRC Press/Balkema , 2018, p. 407-412Conference paper (Refereed)
    Abstract [en]

    Real-time information about the friction coefficient between the tyre and the road can be used to improve active safety systems and is an enabler for autonomous vehicles. Large tyre force excitation is normally required to obtain an accurate friction estimate. This paper quantifies this requirement for four different tyre models on wet salted asphalt at water freezing temperatures. Cost functions and different tyre models are evaluated and the results are compared to a previous study performed for snow conditions. The suitability of commonly used tyre models for friction estimation on snow and wet asphalt has thus been investigated.

  • 2.
    Andersson, Anders
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Driving Simulation and Visualization.
    Kharrazi, Sogol
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle.
    Freight train model for real-time simulation2017In: Dynamics of Vehicles on Roads and Tracks Vol 2: Proceedings of the 25th International Symposium on Dynamics of Vehicles on Roads and Tracks (IAVSD 2017), 14-18 August 2017, Rockhampton, Queensland, Australia, 2017Conference paper (Refereed)
    Abstract [en]

    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.

  • 3.
    Andersson, Anders
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Driving Simulation and Visualization.
    Kharrazi, Sogol
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle.
    Vehicle model quality framework for moving base driving simulators, a powertrain model example2018In: International Journal of Vehicle Systems Modelling and Testing, ISSN 1745-6436, E-ISSN 1745-6444, Vol. 13, no 2, p. 93-108Article in journal (Refereed)
    Abstract [en]

    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.

  • 4.
    Andersson, Anders
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Driving Simulation and Visualization.
    Lidström, Mats
    Peters, Björn
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle.
    Rosberg, Tomas
    Swedish National Road and Transport Research Institute, Infrastructure, Pavement Technology.
    Thorslund, Birgitta
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle.
    Framtagning av loktågsmodell för VTI:s tågsimulator2017Report (Other academic)
    Abstract [en]

    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,

  • 5.
    Andersson, Jan
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users.
    Peters, Björn
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle.
    Visual reaction time abilities relation to driving performance: a simulator based driving performance experiment with visually impaired individuals2018Conference paper (Refereed)
    Abstract [en]

    The literature suggests that ocular diseases are negatively related to driving performance. The factors associated with safe driving is discussed and perceptual abilities are suggested to be related to crash involvement. The present study will focus on i) perceptual tasks or reaction time tasks and ii) attentional and cognitive tasks. All tasks will be visual and cognitive demanding and the objective is to understand how different visual cognitive tasks are related to driving performance. The motive is to be able to discriminate between safe versus unsafe drivers with visual deficits but also understand how different mental mechanisms are related to safe, or unsafe, driving.

    The reaction time tasks are interesting since the reaction time of participants in the study can be measured when performing the driving task. The participants’ reaction time when an object is possible to detect can be measured i) within the complex driving scenario as well as in tasks ii) mimicking driving and iii) “regular” computerized reaction time tasks such as the Simon task. Hence, the objective is two-folded to develop a simulator based method able to discriminate between safe versus unsafe drivers (among the visual deficit population). Second, to pinpoint the importance of visual reaction time and different cognitive tasks on driving performance.

    The cognitive, attentional demanding tasks are not as analyzed at this point but will be elaborated on in the presentation. The tasks are presented in the method section.

    The summarised data on patients with Glaucoma, Cataract, age-related macular degeneration (AMD), and diabetic retinopathy reveal, on a general level, is that ocular diseases impair driver performance.  The literature also suggests, for instance, that not all Glaucoma patients fail on-road driving tests. In summary, the majority of the research literature results indicate, a) general decline in driving performance due to a visual impairment, but b) this is not true for all patients with the same visual deficit.

  • 6.
    Andersson, Jan
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Renner, Linda
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Sandin, Jesper
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction. Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle.
    Fors, Carina
    Swedish National Road and Transport Research Institute, Traffic and road users, Vehicle technology and simulation. Swedish National Road and Transport Research Institute, Traffic and road users, Human Factors in the Transport System.
    Strand, Niklas
    Swedish National Road and Transport Research Institute, Traffic and road users, Vehicle technology and simulation. Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle.
    Hjort, Mattias
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction. Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle.
    Andersson Hultgren, Jonas
    Swedish National Road and Transport Research Institute.
    Almqvist, Sverker
    Swedish National Road and Transport Research Institute.
    Trafiksäkerhetspåverkan vid omkörning av 30-metersfordon2011Report (Other academic)
    Abstract [en]

    The Swedish Road Administration considers permitting longer and heavier trucks on Swedish roads, provided that they do not affect traffic safety. The purpose of the study was to investigate the effect of truck length, particularly accident risk associated with overtaking. Interviewed drivers of 30 meter trucks had not experienced the problems predicted by drivers of ordinary trucks concerning narrow roundabouts and intersections, but mentioned the importance of a supportive truck company, working environment and truck equipment. A simulator study investigated car drivers overtaking trucks 30 m and 18.75 m long on a 2+1 road where two lanes merges to one. The headway time gap was 0.2 sec. (sign.) shorter after overtaking the 30 meter truck in situations where the back was in the same relative position as of the 18.75 meter truck. A field study analysed video-recorded overtakings of a 30 meter and a 24 meter timber truck on a 2+1 road and a two-lane road. No significant differences were found between headway time gaps when overtaking the two trucks, regardless of road type. The latter result should be interpreted with great caution because of unevenly distributed data collected during specific conditions. The conclusions are that longer trucks may have a small negative effect on overtaking situations, and that further field studies are required.

  • 7.
    Andersson, Jonas
    et al.
    RISE.
    Skoglund, Tor
    Sweco Society AB.
    Strand, Niklas
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle.
    The Human-Tech Matrix: A Socio-Technical Approach to Evaluation of Automated Transport Systems2019In: Advances in Intelligent Systems and Computing, Springer Verlag , 2019, Vol. 876, p. 375-380Conference paper (Refereed)
    Abstract [en]

    An automated transport system has the potential to improve traffic safety and flow, but also to the accessibility and comfort for users of the transport system. Realizing the positive effects with automated transport is about shaping regulatory, organizational and technical systems. Here, appropriate evaluation enables steering efforts in the desired direction. The overall aim of this study was to develop a methodological framework that could identify effects of an automated transport system, and outline methods and metrics for evaluation of these effects. We propose a tentative case-based methodology to define measures of the effects of an automated transport system that will give key stakeholders new possibilities to evaluate research and development projects and efforts connected to automation of the transport system, and thereby manage these in a human-centered direction.

  • 8.
    Anund, Anna
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Human Factors in the Transport System.
    Ihlström, Jonas
    Swedish National Road and Transport Research Institute, Traffic and road users, Human Factors in the Transport System.
    Stave, Christina
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle.
    Nybom, Per
    ITRA AB.
    Bälte i buss: observationsstudie av användande och resenärers perspektiv2018Report (Other academic)
    Abstract [en]

    This study aims to evaluate the seat belt usage in buses, to evaluate to what extent information about the need to use the seat belt are provided and to understand travelers' incentives of seatbelt usage. Based on the results the aim was to propose measures to increase the use of a belt when traveling by bus.

    Methods used are observational studies, discussion within focus groups and a web questionnaire. The results from the observation study showed that passenger seat belt usage was 92% in charter service, 50% in commercial liner traffic and 27% in regional liner traffic. The drivers' use was correspondingly 100% in charter service, 79% in commercial liner traffic and 85% in regional liner traffic. The results from the web questionnaire show a lower level of usage. The conclusion is that measures are needed to increase the user rate, especially in line traffic.

    In the observation study, drivers were asked if they remind the passengers to use the seat belt, in the same way the passengers were asked if they have received information when going but charter service or commercial liner traffic. In charter service, 86% experienced they had received information, in commercial liner traffic it was 61% and in regional liner traffic it was 19%. The conclusion is that there are major shortcomings in the information on the belt, which should be addressed, especially in line traffic.

    The decision to use a belt or not is individual. Factors like how old you are, what experience you're having on a safe bus, what kind of road you travel, when you travel and how you're looking at safety generally plays a part.

  • 9.
    Augusto, Bruno
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Driving Simulation and Visualization.
    Kharrazi, Sogol
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle.
    Fröjd, Niklas
    Volvo Group Trucks Technology, VGTT.
    Vehicle dynamics testing in driving simulators: a case study for heavy vehicles2019Report (Other academic)
    Abstract [en]

    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.

  • 10.
    Banks, Victoria A.
    et al.
    University of Southampton.
    Eriksson, Alexander
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle. University of Southampton.
    O'Donoghue, Jim
    Jaguar Land Rover Research.
    Stanton, Neville A.
    University of Southampton.
    Is partially automated driving a bad idea?: Observations from an on-road study2018In: Applied Ergonomics, ISSN 0003-6870, E-ISSN 1872-9126, Vol. 68, p. 138-145Article in journal (Refereed)
    Abstract [en]

    The automation of longitudinal and lateral control has enabled drivers to become “hands and feet free” but they are required to remain in an active monitoring state with a requirement to resume manual control if required. This represents the single largest allocation of system function problem with vehicle automation as the literature suggests that humans are notoriously inefficient at completing prolonged monitoring tasks. To further explore whether partially automated driving solutions can appropriately support the driver in completing their new monitoring role, video observations were collected as part of an on-road study using a Tesla Model S being operated in Autopilot mode. A thematic analysis of video data suggests that drivers are not being properly supported in adhering to their new monitoring responsibilities and instead demonstrate behaviour indicative of complacency and over-trust. These attributes may encourage drivers to take more risks whilst out on the road. © 2017 Elsevier Ltd

  • 11.
    Bazilinskyy, Pavlo
    et al.
    Delft University of Technology.
    Petermeijer, Sebastiaan M.
    Delft University of Technology.
    Petrovych, Veronika
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle.
    Dodou, Dimitra
    Delft University of Technology.
    de Winter, Joost C. F.
    Delft University of Technology.
    Take-over requests in highly automated driving: A crowdsourcing survey on auditory, vibrotactile, and visual displays2018In: Transportation Research Part F: Traffic Psychology and Behaviour, ISSN 1369-8478, E-ISSN 1873-5517, Vol. 56, p. 82-98Article in journal (Refereed)
    Abstract [en]

    An important research question in the domain of highly automated driving is how to aid drivers in transitions between manual and automated control. Until highly automated cars are available, knowledge on this topic has to be obtained via simulators and self-report questionnaires. Using crowdsourcing, we surveyed 1692 people on auditory, visual, and vibrotactile take-over requests (TORs) in highly automated driving. The survey presented recordings of auditory messages and illustrations of visual and vibrational messages in traffic scenarios of various urgency levels. Multimodal TORs were the most preferred option in high-urgency scenarios. Auditory TORs were the most preferred option in low-urgency scenarios and as a confirmation message that the system is ready to switch from manual to automated mode. For low-urgency scenarios, visual-only TORs were more preferred than vibration-only TORs. Beeps with shorter interpulse intervals were perceived as more urgent, with Stevens’ power law yielding an accurate fit to the data. Spoken messages were more accepted than abstract sounds, and the female voice was more preferred than the male voice. Preferences and perceived urgency ratings were similar in middle- and high-income countries. In summary, this international survey showed that people's preferences for TOR types in highly automated driving depend on the urgency of the situation.

  • 12.
    Björklund, Gunilla
    et al.
    Swedish National Road and Transport Research Institute, Society, environment and transport, Mobility, actors and planning processes.
    Forward, Sonja
    Swedish National Road and Transport Research Institute, Society, environment and transport, Mobility, actors and planning processes.
    Janhäll, Sara
    Swedish National Road and Transport Research Institute, Society, environment and transport, Environment.
    Stave, Christina
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle.
    Samspel i trafiken: formella och informella regler bland cyklister2017Report (Other academic)
    Abstract [en]

    Our understanding of cyclists’ behaviour in relation to rules and regulations are rather poor and the same applies to cyclists’ interaction with other road users. The purpose of this project was therefore to explore cyclists’ knowledge of traffic rules but also what determine their own compliance or noncompliance. Participants in the study were 612 people between 18 and 74 years from Gothenburg, Linköping and Stockholm and were recruited through a web panel. A survey was used which asked them about their background, view of themselves as cyclists, own self-compliance, view of others’ compliance, knowledge of rules and various factors that determine their intention to break the rules.

    The results from the study showed that the participants’ regular knowledge was relatively good, at least in terms of behaviours that are prohibited. The participants who thought that a certain behaviour was forbidden also replied that they did this to a lesser extent. Cyclists who stated that they would like to arrive as soon as possible tended to choose more flexible routes (e.g. bike across pedestrian crossings, pavements and roads mainly used by vehicles), whether permitted or not. To a greater extent they also stated that they did not always stop at red lights or at stop signs. Cycle crossings, junctions, pedestrian crossings and pavements were used as examples of places/situations where the rules were considered unclear. Perceived behavioural control and attitude influenced the intention to behave according to three hypothetical scenarios which described how other road users had to break or swerve in order to avoid an accident with the cyclist. This meant that those who intended to behave in the manner indicated believed that it was easy and rather harmless, but also that it was both right and good. However, the most important factor was if they had performed the behaviour in the past, which in turn may have reinforced this view, that is if nothing serious had happened.

  • 13.
    Blissing, Björn
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Driving Simulation and Visualization.
    Bruzelius, Fredrik
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle.
    Exploring the suitability of virtual reality for driving simulation2018In: Proceedings of the Driving Simulation Conference 2018 / [ed] Andras Kemeny, Frédéric Mérienne, Florent Columbet, Stéphane Espié, Antibes, France, 2018, p. 163-166Conference paper (Refereed)
    Abstract [en]

    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.

  • 14.
    Bruzelius, Fredrik
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Körsimulering och visualisering, SIM.
    Kharrazi, Sogol
    Swedish National Road and Transport Research Institute, Traffic and road users, Förare och fordon, FOF.
    Pettersson, Emil
    Volvo GTT.
    Model and Road Surface Sensitivity of Longitudinal Performance Based Standards2016Conference paper (Refereed)
    Abstract [en]

    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.

  • 15.
    Bruzelius, Fredrik
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle.
    Kusachov, Artem
    Winter testing in driving simulators2018Report (Other academic)
    Abstract [en]

    Many traffic accidents are due to winter conditions like slippery roads and limited visibility. The road administrators put a lot of effort into snow removal and de-icing the roads, and the vehicle manufacturers have been working with functionality to support drivers in winter conditions for decades.

    Many issues of driving in winter conditions originate in drivers’ behaviours such as risk taking and lack of awareness. Studying drivers’ behaviour in winter conditions in general, and the effect of various countermeasures of the vehicle, would increase the understanding of the underlying mechanisms and could possibly be used to reduce the accident risks. Motion-base driving simulators are tools frequently used for driving behaviour research. However, the validity of the results of such studies depends to a large extent on the realism of the simulation. The purpose of this project was to study winter simulation with the aim to improve the realism of simulator driving in winter conditions.

    Driving in winter is in many ways different from driving in summer. The difference can to a considerable extent be explained by the tire-to-road interaction. Winter driving is typically characterized by softer motion and slower development of tire forces. In the present project two aspects of the motion have been studied, the motion feedback in the simulator and models for tire-to-snow behaviour.

    Vehicle motion during winter driving is characterized by large vehicle body slip angles and the associated yaw motions. Thus, understanding the importance of yaw motion feedback is essential to simulate winter conditions. A study was designed to investigate the impact that lack of yaw motion will have on the driver, and if it alters his driving behaviour. It was found that the yaw motion alters the driving behaviour, implying that it contains vital information for a wide range of driving situations. A second study was carried out to investigate if the rotation centre, which is a consequence of the yaw and lateral motions, can be used to present valuable information about the vehicle state to the driver. Indicative results suggest that the rotation centre of the motion is valuable to the driver, but further studies are needed. The softer and slower motions of winter driving suggest that pre-positioning of the simulator’s motion platform could be performed to improve the motion envelope. A third implementation study performed in the project suggests this.  

  • 16.
    Cabrall, Christopher D. D.
    et al.
    Delft University of Technology.
    Eriksson, Alexander
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle.
    Lu, Zhenji
    Delft University of Technology.
    Petermeijer, Sebastiaan M.
    Delft University of Technology.
    Current insights in human factors of automated driving and future outlook towards tele-operated remote driving services2018In: International Conference on Intelligent Human Systems Integration: Proceedings of the 1st International Conference on Intelligent Human Systems Integration (IHSI 2018): Integrating People and Intelligent Systems, January 7-9, 2018, Dubai, United Arab Emirates, Springer, 2018, p. 10-12Conference paper (Refereed)
    Abstract [en]

    Across the automotive industry, manufacturers have recently released various Partial Automation systems (SAE Level 2) which allow simultaneous/combined execution of both lateral and longitudinal vehicle control at the same time, yet still require active human supervision/engagement. Current reactive trends will be reviewed across major automotive players regarding differences in terminology, HMI input/outputs, and escalation intervals. Scholarly research is also reviewed pertaining to proactive strategies for driver engagement. Additionally, human factors research and findings will be presented regarding recommendations for situation awareness, human machine interfaces, TOR, as well as shared control concepts. The tutorial will conclude with discussion and brainstorming around outlook toward tele-operated remote driving services (Tele-Driving); what they have to offer beyond assisted/automated driving, autonomous vehicles, and ride-hailing/car-sharing paradigms; as well as the design/conduct of human factors research regarding Tele-Driving.

  • 17.
    Cabrall, Christopher D. D.
    et al.
    Delft University of Technology.
    Petrovych, Veronika
    Swedish National Road and Transport Research Institute, Traffic and road users, Förare och fordon, FOF.
    Happee, Riender
    Delft University of Technology.
    Looking at drivers and passengers to inform automated driver state monitoring of in and out of the loop2018In: Advances in Intelligent Systems and Computing, Springer Verlag , 2018, Vol. 597, p. 695-707Conference paper (Refereed)
    Abstract [en]

    The “drivenger” aim of the current study was to investigate attentional differentiation of drivers (who are in control) from passengers (who have no control) to inform future driver-in-the-loop monitoring/detection systems and facilitate multiple levels of manual/automated driving. Eye-tracking glasses were worn simultaneously by the driver and front seat passenger on 32 on road trips. Halfway en-route, the passenger was tasked with pretending with their eyes to be driving. Converging with a recent and independent drivenger study, our results found differences of higher probabilities of small saccades and significantly shorter blinks from our drivers and pseudo-drivers. Additionally, a new measure of eye eccentricity differentiated between driver/passenger roles. While naturalistic attentional manipulations may not be appropriately safe/available with actual automated vehicles, future studies might aim to further use the eye behavior of passengers to refine robust measures of driver (in)attention with increasing reductions in measurement intrusiveness and data filtering/processing overhead requirements.

  • 18.
    Chugh, Tushar
    et al.
    Chalmers Tekniska Högskola.
    Bruzelius, Fredrik
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle.
    Klomp, Matthijs
    Chalmers Tekniska Högskola.
    Shyrokau, Barys
    Delft University of Technology.
    Design of Haptic Feedback Control for Steer-by-Wire2018In: IEEE Conference on Intelligent Transportation Systems, Proceedings, ITSC, Institute of Electrical and Electronics Engineers Inc. , 2018, p. 1737-1744Conference paper (Refereed)
    Abstract [en]

    This paper illustrates a comparison of different haptic feedback control strategies; primarily focusing on open and closed-loop methods for a Force-Feedback Steer-by-Wire system. Due to shortcomings caused by the feedback motor impedance in the open loop architecture, the tracking performance is deteriorated. Consequently it is shown that the closed-loop solutions provide an improved response within the desired steering excitation range. The closed-loop possibilities, torque and position control, are designed and objectively compared in terms of performance and stability. The controller objectives are inertia compensation and reference tracking. For a given reference, the stability constraint between the controller gains responsible for the two objectives is contrasting in both the methods. Higher bandwidth is achieved for torque controller, whereas the driver arm inertia limits the position control performance. The linear system analysis is supported by the experimental results.

  • 19.
    da Conceicao, V. P.
    et al.
    Chalmers Tekniska Högskola.
    Mendes, J. B.
    Portuguese Naval School.
    Teodoro, M. F.
    Portuguese Naval School.
    Dahlman, Joakim
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle. Chalmers Tekniska Högskola.
    Validation of a Behavioral Marker System for Rating Cadet's Non-Technical Skills2019In: TransNav, International Journal on Marine Navigation and Safety of Sea Transportation, ISSN 2083-6473, E-ISSN 2083-6481, Vol. 13, no 1, p. 89-96Article in journal (Refereed)
    Abstract [en]

    Simulator-based training assumes a very important role in the maritime domain, particularly in the education of Officers Of the Watch (OOW). In the Portuguese Navy, most of the cadet's skills as future OOW rely on the success of this training. Beyond theory and technical training, the development of nontechnical skills is a key factor for obtaining officers capable of identifying and solving problems. To optimize the training and development of non-technical skills, using the Portuguese Naval Academy Simulator, a previously designed Behavioral Marker System model was further assessed. The revised model, which comprises new parameters such as the effectiveness of the task, was validated through a set of simulated sessions, where 11 instructors and 48 students participated. After each session, data was collected with questionnaires and focus group discussion, focusing on the quality and usability of the model and on the design of the scenario. The results show that the revised model, positively addresses the limitations found on the previous version, and it has received encouraging feedback from both instructors and cadets. This new model is now under implementation in all the Naval Academy course programs, and future research aims to digitalize the behavior markers.

  • 20.
    De Saxe, Christopher
    et al.
    WITS - University of the Witwatersrand.
    Kural, Karel
    HAN University of Applied Sciences.
    Kharrazi, Sogol
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle. Linköpings Universitet.
    Schmidt, Franziska
    IFSTTAR/MAST/EMGCU.
    Van Geem, Carl
    Belgian Road Research Centre.
    Robert, Berman
    WITS - University of the Witwatersrand.
    Woodrooffe, John
    University of Michigan.
    Cebon, David
    CAM - University of Cambridge.
    FALCON III: Defining a performance-based standards framework for high capacity vehicles in Europe2018Conference paper (Refereed)
    Abstract [en]

    The FALCON project (“Freight and Logistics in a Multimodal Context”) is a collaborative effort funded by the Conference of European Directors of Roads (CEDR), and has set out to address ambitious carbon emission reduction targets set by the European Commission. A primary goal of the project is to define a potential Performance-Based Standards (PBS) framework for cross-border road freight transport in Europe. First, a representative fleet of heavy vehicle combinations carrying modular loading units was formulated in collaboration with industry. The fleet was then simulated against a wide range of potential performance standards sourced from various countries. These findings together with expert opinion were then used to draft recommendations for a PBS framework for Europe.

  • 21.
    Dols, Juan F.
    et al.
    University Polytechnic of Valencia, Spain.
    Peters, Björn
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle.
    Thorslund, Birgitta
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle.
    Usefulness and acceptance of assessments of drivers with disabilities in simulation test rigs2018Conference paper (Refereed)
    Abstract [en]

    The legal reference in the field of driving license in the EU is currently the 2006/126/EC Directive, which stipulates that driving licenses shall be granted only to those who meet medical requirements and pass a driving test. This Directive has recently been updated with the Directive EU 2015/653. Actually, there is a lack of knowledge in the application of validated procedures for assessing (potential) drivers of adapted vehicles. The objective of this paper it is to present experimental results of driving assessment procedures developed for assessing drivers with impairments –both motor and sensory-. This assessment is based on performing a series of practical tests in a static test rig and a low-cost driving simulator.

  • 22.
    Dukic Willstrand, Tania
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Human Factors in the Transport System.
    Anund, Anna
    Swedish National Road and Transport Research Institute, Traffic and road users, Human Factors in the Transport System.
    Pereira Cocron, Marta
    TU Chemnitz, Germany.
    Griesche, Stefan
    DLR, Germany.
    Strand, Niklas
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle.
    Troberg, Sonja
    Scania, Sweden.
    Zanovello, Luca
    Ducati, Italy.
    Collecting end-users needs regarding driver state-based automation in the ADAS&ME project2018Conference paper (Refereed)
    Abstract [en]

    The EU funded project ADAS&ME (Adaptive ADAS to support incapacitated drivers & Mitigate Effectively risks through tailor made HMI under automation) develops adapted Advanced Driver Assistance Systems. A web based survey was designed to collect the opinion of ADAS&ME end-users about automated functions that could support the driver/rider during different driving tasks. In total, 1094 persons answered the survey. The results reveal that most of the participants had heard of automated functions previously, and that about half of them also had experience using such functions. Several participants indicated concerns about data security. Furthermore, the results give an insight into how end-users perceive automation and what they see as advantages and limitations for implementation of automated driving systems corresponding to the ADAS&MEs’ goals.

  • 23.
    Dukic Willstrand, Tania
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Human Factors in the Transport System.
    Anund, Anna
    Swedish National Road and Transport Research Institute, Traffic and road users, Human Factors in the Transport System.
    Pereira Cocron, Marta
    TU Chemnitz.
    Griesche, Stefan
    DLR.
    Strand, Niklas
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle.
    Troberg, Sonja
    Scania.
    Zanovello, Luca
    Ducati.
    Nikolau, Stella
    CERTH.
    Collecting end-user needs regarding driver statebased automation in ADAS&ME project2018Conference paper (Other academic)
  • 24.
    Eriksson, Alexander
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle.
    Augusto, Bruno
    Swedish National Road and Transport Research Institute, Traffic and road users, Driving Simulation and Visualization.
    Strand, Niklas
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle.
    Sandin, Jesper
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle.
    Drivers’ recovery performance in a critical run-off-road scenario: A driving simulator study2018In: Proceedings of the 6th Humanist Conference, The Hague, Netherlands, 13-14 June 2018 / [ed] Nicole Van Nes, Charlotte Voegelé, 2018Conference paper (Other academic)
    Abstract [en]

    Single vehicle accidents are commonly caused by fatigue and distractionand 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 yawdeviation 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 failureof automated lane keeping systems, leading to lane departures. Furthermore, significant learning effects was found, providing recommendations for further studies into run-off-road experiments.

  • 25.
    Eriksson, Alexander
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle. University of Southampton.
    de Winter, Joost
    Delft University of Technology.
    Stanton, Neville A.
    University of Southampton.
    A toolbox for automated driving on the STISIM driving simulator2018In: MethodsX, ISSN 1258-780X, E-ISSN 2215-0161, Vol. 5, p. 1073-1088Article in journal (Refereed)
    Abstract [en]

    Driving simulators have been used since the beginning of the 1930s to assist researchers in assessing driver behaviour without putting the driver in harm's way. The current manuscript describes the implementation of a toolbox for automated driving research on the widely used STISIM platform. The toolbox presented in this manuscript allows researchers to conduct flexible research into automated driving, enabling independent use of longitudinal control, and a combination of longitudinal and lateral control, and is available as an open source download through GitHub. The toolbox allows the driver to adjust parameters such as set speed (in 5 kph increments) and time-headway (in steps of 1, 1.5, and 2 s) as well as automation mode dynamically, while logging additional variabless that STISIM does not provide out-of-the-box (time-headway, time to collision). Moreover, the toolbox presented in this manuscript has gone through validation trials showing accurate speed, time-headway, and lane tracking, as well as transitions of control between manual and automated driving.

    • A toolbox was developed for STISIM driving simulators.
    • The toolbox allows for automated driving.
    • Functionality includes tracking of speed, headway, and lane.
  • 26.
    Forward, Sonja
    et al.
    Swedish National Road and Transport Research Institute, Society, environment and transport, Mobility, actors and planning processes.
    Lindgren, Hanna
    Swedish National Road and Transport Research Institute, Society, environment and transport, Transport economics.
    Stave, Christina
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle.
    Henriksson, Per
    Swedish National Road and Transport Research Institute, Society, environment and transport, Mobility, actors and planning processes.
    Nyberg, Jonna
    Swedish National Road and Transport Research Institute, Society, environment and transport, Mobility, actors and planning processes.
    Effekterna av begränsat antal handledarskap: en utvärdering2018Report (Other academic)
    Abstract [en]

    Formerly, a private driving tutor could have an unlimited number of approvals, but new regulations limit the number to 15. The overall purpose of this study is to determine whether this limit on the number of approvals for practice driving a private tutor can have has had any effect on unlawful driving school operations. Another important aim is to offer suggestions for alternative measures to curtail such activity in the driver’s training field. We have taken three approaches to addressing these issues, i.e.: a register study, an interview study, and a survey study. The results of the interview study indicate that, regarding illegal driving school activities, a host of services are available for purchase: falsified tutoring permits, private driving instructions, written examinations filmed on site and that others can access, help to pass the theoretical test by providing the correct answers via an earpiece and booking the appointment for a driving test. According to the interviewees, the most common is to offer private driving tutoring in return for payment. Opinions vary as to the scope of such unlawful activities from minor to extremely extensive in scope. However, the results of the survey study offer indications that relatively extensive unlawful activities are taking place. As to whether the regulations had a positive or negative impact on the unlawful driving school activities, the interviewees were in relative agreement that the regulations had no effect whatsoever. The argument was that those currently engaged in the illegal driving schools, or at any rate the more serious offenders, are sophisticated enough that they would surely circumvent these regulations. Despite this some of them wanted further reductions, even though they did not believe that this reduction would suffice. For them it was important to clearly demonstrate that it is a private instruction and no a professional activity. In general terms, the study identified deficiencies in the current driving licence system that could undermine confidence that Swedish driving licences have been obtained legally. The report ends with 16 different measures which could curtail unlawful activity. This means that no single measure will solve the problem by itself.

  • 27.
    Hedström, Ragnar
    et al.
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Rosberg, Tomas
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle.
    Uppkörda spårväxlar: orsak och konsekvens2019Report (Other academic)
    Abstract [en]

    A trailing point where the tongues are not in the correct position could be at risk of being worn down when a vehicle passes through the point switch. The data from ”Lupp”, the Swedish Transport Administration’s database, shows that there were a total number of 630 worn point switches during the years 2014–2017. Of these, 16 objects which related to track locks have been disregarded. In cases where a point switch has been worn due to SPAD (a signal passed at danger), 49 incidents in total, these have also been disregarded. The reason for this is because each individual incident of this type is investigated as an individual case. 76 incidents where it could not be determined whether or not the switch was worn due to insufficient information have been disregarded. Of the total number of objects obtained from Lupp, 489 have been identified as worn point switches and have been used as basis for the analyses conducted in this project.

    There are many possible causes as to why a point switch gets worn down, such as work machinery, incorrect handling, switch malfunctions, vehicle malfunctions, lack of maintenance, etc. Because there are multiple possible causes for the wearing down, we also see variation in the consequences depending on the type of switch, where it is placed (e.g. along a main route or along sidings), and the type of vehicles passing the point switch.

    It has generally been difficult to discern any clear pattern regarding worn point switches based on the switch model, operation sites, cause or effect because of the large number of variations concerning these factors. At the same time, it can be noted that there is an issue with worn point switches when looking at traffic aspects (disrupted trains, hours of downtime), as well as costs and time spent repairing the damaged point switch. However, the actual costs associated with worn point switches have not been a point of analysis in this project.

  • 28.
    Hedström, Ragnar
    et al.
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Rosberg, Tomas
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle.
    Wikberg, Åsa
    Swedish National Road and Transport Research Institute, Society, environment and transport, Transport economics.
    Prognosmodell för framtida resurs- och kompetensbehov inom järnvägsbranschen2019Report (Other academic)
    Abstract [en]

    According to the 2018–2029 National Plan for the Transport System, SEK 125 billion are to be set aside for the operation, maintenance and reinvestments of state railways during that period. This is an increase of about 40 percent compared with the corresponding plan for 2014–2025. Increased funding implies a greater volume of activities and indications have been received from players in the railway industry that all the resources and competences required to carry out planned railway, underground and tramway projects are not available. The Swedish Transport Administration therefore initiated a work process to produce a practical and useful forecast model that would predict the future resource and competence needs of the entire railway industry. Considering the complex structure of the railway industry, the wide variety of areas of activity and all the data (which was gathered manually for this project) needed for a forecast model, it transpired that the work task could not be completed within the framework of the project.

    The purpose of the project and this report has therefore been limited to suggesting a structure for the forecast model and, by using examples of four types of project - replacement of switches, replacement of tracks, building of passing loops, and the extension of double tracks - showing how the demand for resources and competences can be forecast. No analysis has been made of the supply side, that is, the current availability of manpower, retirements and study programmes. The reason for this is because there are no statistics that can be readily used to specify these parameters specifically for all the occupational groups and areas of activity of the railway industry. Because of this, the drafted version of the forecast model cannot be linked to the supply side and therefore it cannot show which occupational groups are expected to have a surplus or deficit of resources and competences.

  • 29.
    Hjort, Mattias
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle.
    Mönsterdjupets inverkan på väggrepp på is för släpvagnsdäck till tunga fordon: jämförande tester2019Report (Other academic)
    Abstract [en]

    In Sweden the current regulation for minimum tread depth for heavy vehicles in the winter period is different for trailer axles compared to drive or steer axles. While the requirement for the latter axles are 5 mm tread depth, on trailer axles 1,6 mm is required.

    The purpose of this study has been to investigate whether there is reason to increase the tread depth requirement for heavy vehicle trailer tyres during the winter period in Sweden, and if so, suggest a new tread depth limit. The study was limited to ice conditions, and ice grip for a number of different trailer tyres with different tread depth was measured on smooth ice in VTI’s tyre test facility.

    Before conducting the test there was no clear hypothesis for how the ice grip would be affected by a lower tread depth. An increase of the grip, as well as a decrease, were both possible outcomes for a diminished tread depth.

    Four different tire models in a dimension common for heavy vehicle trailer tyres (385/55-R22.5) were chosen for the tests. Every model was tested in a new state, as well as with 5, 3, and 1.6 mm tread depth. It was decided to use naturally worn tyres which meant that in total 16 different tyres were used in the study. The difficult task of finding identical tyre models and dimensions with specified tread depth forced us to also include some tyres with the larger profile (285/65-R22.5). This is however not considered to affect the results of the test. All the tyres were winter tyres, and most of them were also marked with the 3PMSF symbol, which means that they have passed a standardized grip test on snow.

    Both brake and steer test were conducted. Five different grip related attributes were investigated: peak friction at braking, friction at locked wheel braking, cornering stiffness, cornering peak friction, and cornering friction with large slip angle

  • 30.
    Hjort, Mattias
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle.
    Vinterdäck till cykel: ett jämförande test2018Report (Other academic)
    Abstract [en]

    The purpose of this study has been to compare the winter road grip of various bicycle tyres, as well as a pair of unstudded winter tyres, through cycling tests. In addition to grip, other characteristics that could be important to a cyclist, such as rolling resistance and wear resistance, were also tested.

    The tyre’s grip on ice was tested by brake tests and manoeuvring tests indoors in an ice hockey rink. Four different test drivers were used to capture differences in driver behaviour, as well as to get a variation in the cyclist’s weight. The tyre rolling resistance was measured by indoor coast-down tests. Finally, the grip was tested on dry and wet asphalt by outdoor brake tests. Between the various tests, the studded tyres were examined with regard to the number of lost studs. In total, seven different studded tyres, two unstudded winter tyres and a summer tyre were tested.

    The brake tests on dry and wet asphalt could not show any difference in performance between the different tyres. The winter tyres, studded as well as unstudded, had as good grip on asphalt as the tested summer tyre. In the case of ice grip, the two tyres with the highest number of studs, 240, were clearly superior to the others.

    The rolling resistance tests showed differences between the different tyres and it is not the number of studs but rather the rubber properties and the puncture protection that has the greatest impact on the rolling resistance. The wear tests indicated that some of the tested models may be particularly prone to losing studs, but as the tests included only two samples of each tyre model, it is not possible to draw certain conclusions regarding wear resistance.

  • 31.
    Hjort, Mattias
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle.
    Eriksson, Olle
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Bruzelius, Fredrik
    Swedish National Road and Transport Research Institute, Traffic and road users, Driving Simulation and Visualization.
    Comprehensive study of the performance of winter tires on ice, snow, and asphalt roads: The influence of tire type and wear2017In: Tire Science and Technology, ISSN 0090-8657, Vol. 45, no 3, p. 175-199Article in journal (Refereed)
    Abstract [en]

    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.

  • 32.
    Hjort, Mattias
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle.
    Gustafsson, Susanne
    Swedish National Road and Transport Research Institute, Traffic and road users, Traffic Safety and Traffic System.
    Henriksson, Per
    Swedish National Road and Transport Research Institute, Society, environment and transport, Mobility, actors and planning processes.
    Forsman, Åsa
    Swedish National Road and Transport Research Institute, Traffic and road users, Traffic safety, society and road-user.
    Tunga lastbilars däckanvändning och olycksrisk vintertid2017Report (Other academic)
    Abstract [en]

    In Sweden, it is today regulated that winter tyres must be used on the drive axle of heavy vehicles (total weight in excess of 3,500 kg) during the winter season period, December 1 to March 31, in case of winter conditions. This requirement is based entirely on accessibility, and it is considered that winter tyres on the drive axle provides better conditions for heavy vehicles to go forward in icy and snowy conditions. Previous accident risk studies have not been able to demonstrate that the use of winter tyres instead of summer tyres for heavy vehicles in winter could lead to reduced risk of accidents. In Norway and Finland, the regulations on tyre use for heavy vehicles in winter time has recently been revised. Prior to a discussion of possible regulations in Sweden on winter tyres also on other axles, there is reason to update the previous accident risk studies. The purpose of this study has been to calculate the risk of accidents on ice/snow conditions for comparison between summer and winter tires for heavy trucks. The study was performed according to the method previously used in the VTI studies conducted in 2000 and 2008. This meant that two questionnaires were sent out by the end of the winter 2015/2016. One survey to analyse the vehicle mileage on ice/snow conditions with different combinations of tires, and one questionnaire directed solely to the vehicle owners whose vehicles according Strada during the winter season have been involved in an injury accident. Accident risk calculations were limited to vehicles with a total weight of 16 tons.

  • 33.
    Hjort, Mattias
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle.
    Niska, Anna
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Mätning av cykeldäcks friktionsegenskaper som underlag för simuleringsstudier2018Report (Other academic)
    Abstract [en]

    In this project measurements of a bicycle tyre on an asphalt surface have been carried out in the VTI stationary tyre testing facility, in order to provide slip curves describing friction properties of the tyre. The measurement results have then been used to obtain tyre parameters for simulation purposes. The following tyre parameters have been measured: cornering stiffness, camber stiffness, brake slip stiffness and lateral relaxation length.

    The tested tyre generated a maximum friction level of approximately 1.0 on the asphalt. Typical values of the tyre parameters were: normalized cornering stiffness 0.3; standardized camber stiffness 0.01; standard brake slip stiffness 250. Compared to the few previously published measurements on bicycle tyres, cornering stiffness was generally about 50 percent higher than previously reported. The values for camber stiffness correspond well to the values shown by a racing tyre study but are 25–50 percent lower than the values measured on more normal tyres in another study. For brake slip stiffness there are no previous measurements to compare with. Measurement of the lateral relaxation length was unfortunately affected by problems with the measuring equipment and we could not determine the relaxation length with the desired accuracy. From the measurements, we estimate the relaxation length to 200–300 mm for the tested tire, which is a factor 2–3 to greater than reported in the only earlier study that measured relaxation length for bicycle tyres.

  • 34.
    Hjälmdahl, Magnus
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle.
    Cunto, Flavio
    Universidade Federal do Ceara.
    Jacques, Maria Alice Prudêncio
    University of Brasilia.
    Editorial2017In: Accident Analysis and Prevention, ISSN 0001-4575, E-ISSN 1879-2057Article in journal (Refereed)
    Abstract [en]

    Road traffic injuries and loss of life is one of the major global health problems today with 1.24 million people killed annually, i.e. one person every 25 s is killed in a road crash. Many countries have learnt to mitigate the problems associated with road traffic crashes but there is still much more to be done. Estimates indicate that, unless action is taken over the next 15 years, the number of annual fatalities in road crashes may rise to 2.4 million, with the increase occurring in low and middle-income countries.

    There is a great necessity for global cooperation to stop the growth of traffic fatalities. To reverse this trend, knowledge, information and experience from success stories and good practice must be shared. Road Safety on Five Continents (RS5C) is an international conference aiming at increasing road safety globally by providing a platform for this essential knowledge exchange and helping the participating countries to find a good balance between road safety and mobility.

    The foundation of the RS5C is in state of the art research and good practice. By providing a mutual ground for sharing knowledge and a forum to discuss mutual problems and their solutions, researchers, officials and other stakeholders can learn from results, experiences and success stories.

    RS5C aims to be a leading source of research results, information and interaction in the road transport area with a focus on safety and health associated with road transport. This aim is accomplished by cooperation with local as well as global organisations to ensure that RS5C meets local needs with global state of the art. Moreover, RS5C will produce papers of high scientific quality that are open and accessible for everyone.

    The 12 peer-reviewed papers in this special issue cover a wide range of topics, demonstrating a broad spectrum of road safety issues from motorized to non-motorized road users, as well as vehicle, road and environmental conditions.

  • 35.
    Hjälmdahl, Magnus
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Förare och fordon, FOF.
    Krupenia, Stas
    Scania.
    Thorslund, Birgitta
    Swedish National Road and Transport Research Institute, Traffic and road users, Förare och fordon, FOF.
    Driver behaviour and driver experience of partial and fully automated truck platooning: a simulator study2017In: European Transport Research Review, ISSN 1867-0717, E-ISSN 1866-8887, Vol. 9, no 1, article id 8Article in journal (Refereed)
    Abstract [en]

    This paper builds our knowledge of truck driver behaviour in and experience of automated truck platooning, focusing on the effect of partially and fully automated truck platoons on driver workload, trust, acceptance, performance, and sleepiness.

    Twenty-four male drivers experienced three conditions in a truck driving simulator, i.e., baseline, partial automation, and full automation: the baseline condition was driving with standard cruise control; partial automation was automated longitudinal control ten metres behind the truck in front, with the driver having to steer; and full automation was automated longitudinal and lateral control. Each condition was simulated in three situations: light traffic, heavy traffic, and heavy traffic plus fog.

    The experiment demonstrated that automation affects workload. For all workload measures, partial automation produced higher workload than did the full-automation or baseline condition. The two measures capturing trust were consistent and indicated that trust was highest under the baseline condition, with little difference between partial and full automation. Driver acceptance of both levels of automation was lower than acceptance of baseline. Drivers rated their situation awareness higher for both partial and full automation than for baseline, although both levels of automation led to higher sleepiness.

    The challenge when implementing truck platooning is to develop a system, including human–machine interaction (HMI), that does not overburden the driver, properly addresses driver sleepiness, and satisfies current legislation. The system also must be trusted and accepted by drivers. To achieve this, the development of well-designed HMI will be crucial.

  • 36.
    Islam, Md Manjurul
    et al.
    Chalmers Tekniska Högskola.
    Fröjd, Niklas
    Volvo Group Trucks Technology.
    Kharrazi, Sogol
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle.
    Jacobson, Bengt
    Chalmers Tekniska Högskola.
    How well a single-track linear model captures the lateral dynamics of long combination vehicles2019In: Vehicle System Dynamics, ISSN 0042-3114, E-ISSN 1744-5159Article in journal (Refereed)
    Abstract [en]

    The effect of centre-of-gravity heights on the high-speed performance measures of long combination vehicles including truck with double centre-axle trailers, Nordic, and A-double combination vehicles is investigated. The high fidelity three-dimensional models, used in this research, are validated against physical test data. These models are often accurate in terms of the actual dynamic behaviours of the vehicle. On the other hand, the simple yaw-plane single-track models with linear tires require less number of vehicle parameters. In this paper, it is investigated how accurate the estimations of performance measures are at high forward speeds by such single-track linear (STL) models. The influence of load height is especially studied. The high-speed performance-based standard or PBS measures considered are rearward amplifications of both lateral acceleration and yaw velocity; lateral load transfer; yaw damping and high-speed transient offtracking. The results show that tire relaxation has a large effect and it is rather easy to add to an STL model, so it is assumed to be modelled in STL. With realistically high payload and a required accuracy of PBS measures of approximately 10%, only the accuracy of rearward amplification of yaw velocity calculated by the frequency response is fulfilled by the STL. With low payload, the same statement is valid, but with around 5% in required accuracy. The roll dynamics effects are more important than the tire non-linearities.

  • 37.
    Jacobson, Bengt J H
    et al.
    Chalmers.
    Sundström, Peter
    Kharrazi, Sogol
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle.
    Fröjd, Niklas
    Islam, Manjurul
    Chalmers.
    An Open Assessment Tool for Performance Based Standards of Long Combination Vehicles2017Report (Other academic)
    Abstract [en]

    The project “Performance Based Standards for High Capacity Transports in Sweden” (Performance Based Standards for High Capacity Transports in Sweden, 2013-2017) have generated a first version of an open PBS assessment tool, OpenPBS. The tool uses models and computations to calculate Performance Based Standards (PBS) measures for combination vehicles. The tool targets Long Combination Vehicles (LCVs, typically 25-35 m) but it can also calculate PBSes for shorter combinations and solo units. This report describes the tool. The report explains the concepts selected for the tool. Future developments are proposed.

  • 38.
    Johnsen, Annika
    et al.
    IfeS.
    Strand, Niklas
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle.
    Andersson, Jan
    Swedish National Road and Transport Research Institute, Traffic and road users.
    Patten, Christopher
    Swedish National Road and Transport Research Institute, Society, environment and transport, Mobility, actors and planning processes.
    Kraetsch, Clemens
    IfeS.
    Takman, Johanna
    Swedish National Road and Transport Research Institute, Society, environment and transport, Transport economics.
    Eriksson, Gabriella (Contributor)
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle.
    Lindgren, Hanna (Contributor)
    Swedish National Road and Transport Research Institute, Society, environment and transport, Transport economics.
    Možina, Katarina (Contributor)
    AMZS.
    Rey, Alba (Contributor)
    ACASA.
    Literature review on the acceptance and road safety, ethical, legal, social and economic implications of automated vehicles2017Report (Other academic)
    Abstract [en]

    This deliverable summarizes the findings of an extensive literature review on the acceptance, behavioural intentions, road safety, as well as ethical, legal, social (ELSI) and economic considerations in the scope of vehicle automation.

    The theoretical fundaments and relevant findings of recent public opinion research regarding user acceptance of automation are presented. Also the view of organised stakeholders is taken into account.

    Regarding road safety there is a potential for increased road safety but drivers tend to pick up non-related driving tasks instead. These problems are due to several traditional HMI concerns. In the future autonomous cars must make decisions that touch on ethical issues that have not yet been sufficiently and transparently discussed. Although in many countries legislation is now reacting to the new technology, many aspects – like liability and privacy / data protection – are not yet regulated by law. Automated vehicles promise to have several clear benefits that might change the entire transport system. The positive externalities that come from the technological advantages of automated vehicles might be outweighed by the negative externalities coming from the potential increases in travelling by private vehicles.

  • 39.
    Kharrazi, Sogol
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle.
    Assessing dynamics of heavy vehicles in a driving simulator2018In: Proceedings of DSC 2018 EUROPE 17th Driving Simulation & Virtual Reality Conference & Exhibition September 2018, Antibes, France, 2018Conference paper (Refereed)
  • 40.
    Kharrazi, Sogol
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle.
    Performance Based Standards Project In Sweden2018Conference paper (Refereed)
    Abstract [en]

    There is a great interest in increasing the efficiency of the transport system in Sweden, which makes the High Capacity Transports (HCT) an attractive solution. To gain more knowledge about HCT vehicles and their effects on traffic safety, infrastructure and environment, the Swedish government is undertaking a large research program focused on HCT vehicles in Sweden. One of the projects in the HCT program was “Performance based standards for high capacity transport in Sweden”. This project started at the end of 2013 to investigate the applicability of a regulatory framework based on performance based standards in Sweden, taking into consideration the winter road conditions. This paper presents a summary of the main outcomes of the project, which ended in 2017.

  • 41.
    Kharrazi, Sogol
    Swedish National Road and Transport Research Institute, Traffic and road users, Förare och fordon, FOF.
    Performance of High Capacity Vehicles, Winter Versus Summer2016Conference paper (Refereed)
    Abstract [en]

    The transport sector is facing a major challenge to reduce energy consumption and limit environmental impact; therefore, there is a great interest in increasing the efficiency of the transport system in Sweden, which makes the High Capacity Vehicles (HCVs) an attractive solution. In order to introduce HCVs in Sweden, the existing regulations should be modified; one approach is to use performance based standards (PBS) as in e.g. Australia and Canada. However, it is very important that the winter road conditions in Sweden is considered and a PBS system suitable for Swedish condition is developed. In this paper performance of a selection of HCVs are compared for both summer and winter condition, which shows a strong correlation between the two.

  • 42.
    Kharrazi, Sogol
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle.
    Almen, Marcus
    SAAB.
    Frisk, Erik
    Linköpings Universitet.
    Nielsen, Lars
    Linköpings Universitet.
    Extending behavioral models to generate mission-based driving cycles for data-driven vehicle development2018In: IEEE Transactions on Vehicular Technology, ISSN 0018-9545, E-ISSN 1939-9359, Vol. 68, no 2, p. 1222-1230Article in journal (Refereed)
    Abstract [en]

    Driving cycles are nowadays to an increasing extent used as input to model-based vehicle design and as training data for development of vehicles models and functions with machine learning algorithms. Recorded real driving data may underrepresent or even lack important characteristics, and therefore there is a need to complement driving cycles obtained from real driving data with synthetic data that exhibit various desired characteristics. In this paper, an efficient method for generation of mission-based driving cycles is developed for this purpose. It is based on available effective methods for traffic simulation and available maps to define driving missions. By comparing the traffic simulation results with real driving data, insufficiencies in the existing behavioral model in the utilized traffic simulation tool are identified. Based on these findings, four extensions to the behavioral model are suggested, staying within the same class of computational complexity so that it can still be used in large scale. The evaluation results show significant improvements in the match between the data measured on the road and the outputs of the traffic simulation with the suggested extensions of the behavioral model. The achieved improvements can be observed with both visual inspection and objective measures. For instance, the 40% difference in the relative positive acceleration (RPA) of the originally simulated driving cycle compared to real driving data was eliminated using the suggested model.

  • 43.
    Kharrazi, Sogol
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle.
    Augusto, Bruno
    Swedish National Road and Transport Research Institute, Traffic and road users, Driving Simulation and Visualization.
    Fröjd, Niklas
    Volvo.
    Vehicle dynamics testing in motion based driving simulators2019In: Vehicle System Dynamics, ISSN 0042-3114, E-ISSN 1744-5159Article in journal (Refereed)
    Abstract [en]

    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.

  • 44.
    Kharrazi, Sogol
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle.
    Bruzelius, Fredrik
    Swedish National Road and Transport Research Institute, Traffic and road users, Driving Simulation and Visualization.
    Sandberg, Ulf
    Swedish National Road and Transport Research Institute, Society, environment and transport, Environment.
    Performance based standards for high capacity transports in Sweden: FIFFI project 2013-03881: final report2017Report (Other academic)
    Abstract [en]

    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.

  • 45.
    Kharrazi, Sogol
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle.
    Nielsen, Lars
    Linköpings Universitet.
    Frisk, Erik
    Linköpings Universitet.
    Design cycles for a given driving mission2018In: Dynamics of Vehicles on Roads and Tracks Vol 1: Proceedings of the 25th International Symposium on Dynamics of Vehicles on Roads and Tracks (IAVSD 2017), 14-18 August 2017, Rockhampton, Queensland, Australia / [ed] Maksym Spiryagin, Timothy Gordon, Colin Cole, Tim McSweeney, London: CRC Press, 2018, Vol. 1, p. 323-328Conference paper (Refereed)
    Abstract [en]

    Representative driving cycles are of key importance for design and dimensioning of powertrains. One approach for generation of representatives driving cycles is to define relevant driving missions which include different street types, obstacles and traffic conditions, and simulate them in a traffic simulation tool. Such a simulation approach will also require representative driver models to generate the speed profiles for the defined driving missions. Feasibility of this approach is investigated in this paper.

  • 46.
    Kural, Karel
    et al.
    HAN University of Applied Sciences.
    de Saxe, Christopher C
    University of Cambridge.
    Kharrazi, Sogol
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle.
    Asp, Thomas
    Trafikverket.
    Kraaijenhagen, Ben
    MAN Truck & Bus AG.
    Pauwelussen, Joop
    Council for Scientific and Insustrial Research, South Africa.
    Smart infrastructure access policy: a highway towards more efficient road transport2018In: Proceedings of the 7th Transport Research Arena (TRA), Vienna, Austria, 16-19 April 2018, 2018Conference paper (Refereed)
    Abstract [en]

    This paper describes interim results of the ongoing CEDR-funded "FALCON" project, which aims to introduce a step improvement in transport efficiency in Europe through the definition of a new performance-oriented legislative framework for road freight transport, thus ensuring a proper match between vehicles and the infrastructure. A Smart Infrastructure Access Policy (SIAP) is being developed as the primary method of regulation, in which policy explicitly specifies the performance level required from the road freight vehicle with respect to safety, manoeuvrability, infrastructure loading, and environmental impact, while giving consideration to national topologies and operational conditions. This method is fundamentally different to the prescriptive approach which mandates only mass and dimension limits of vehicles. The prescriptive approach only indirectly and often ineffectively ensures acceptable vehicle performance, as is the case of current prescriptive European legislation (96/53/EC).

  • 47.
    Lidestam, Björn
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle.
    Bullerskydd med hastighetsdämpande egenskaper2019Report (Other academic)
    Abstract [en]

    The purpose was to demonstrate that a successively denser interval of vertical markings on noise barriers near the road can slow down the mean speed. The concept has the potential to be a cost-efficient alternative or complement to road markings and road signs.

    The method for investigation was a field experiment to measure the speed before, during, and after the time period when the test markings were mounted.

    The results showed no effect of the test markings. It is possible that another type of traffic environment is needed than the type studied in the current field experiment in order to affect the drivers to slow down.

  • 48.
    Lidestam, Björn
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle.
    Läsbarhet och synbarhet av vägmärken med reflexfolie: ett fältexperiment i mörker samt enkätstudier2018Report (Other academic)
    Abstract [en]

    Background: Road signs are crucial for informing road users and need to be bright enough to be visible and readable, but not so bright that they cause glare. The brightness levels of road signs should also be appropriate for the vast majority of road users.

    Purpose: The purpose was to evaluate readability of road signs of retroreflection classes RA2 and RA3B, with regard to factors affecting the retroreflection per se, amount of light onto the signs, and how well the driver sees. Objective measures of reading distance and visual status, and subjective measures of how different categories of drivers experience that they detect, read, and experience glare from road signs were also to be taken into account.

    Methods: A field experiment measured reading distance (and visual acuity and contrast); and questionnaire studies measured opinions and experiences from different driver categories concerning driving in darkness in general, and about properties of road signs in darkness in particular.

  • 49.
    Lidestam, Björn
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle.
    Eriksson, Lars
    Karlstads Universitet.
    Eriksson, Olle
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Speed perception affected by field of view: Energy-based versus rhythm-based processing2019In: Transportation Research Part F: Traffic Psychology and Behaviour, ISSN 1369-8478, E-ISSN 1873-5517, Vol. 65, p. 227-241Article in journal (Refereed)
    Abstract [en]

    Two experiments were carried out to test speed perception dependency on field of view (FoV), virtual road markings (VRMs), and presentation orders. The primary purpose was to examine how the extent of the optic flow (foremost peripherally–vertically) informs the driver about egospeed. A second purpose was to examine different task demands and stimulus characteristics supporting rhythm-based versus energy-based processing. A third purpose was to examine speed changes indicative of changes in motion sensitivity. Participants were tested in a car simulator, with FoV resembling low front-door windows, and with VRMs inside the car. Three main results were found. Larger FoV, both horizontally and peripherally–vertically, significantly reduced participants' speed, as did VRMs. Delineator posts and road center lines were used for participants' rhythm-based processing, when the task was to drive at target speeds. Rich motion-flow cues presented initially resulted in lower egospeed in subsequent conditions with relatively less motion-flow cues. The practical implication is that non-iconic, naturalistic and intuitive interfaces can effectively instill spontaneous speed adaptation in drivers.

  • 50.
    Lidestam, Helene
    et al.
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics. Linköpings Universitet.
    Camén, Carolina
    Linköpings Universitet.
    Lidestam, Björn
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle. Linköpings Universitet.
    Evaluation of cost drivers within public bus transports in Sweden2018In: Research in Transportation Economics, ISSN 0739-8859, E-ISSN 1875-7979Article in journal (Refereed)
    Abstract [en]

    The supply of public transport in Sweden has been continuously increasing and as a consequence thereof, the cost for bus traffic has also increased. However, many indicators show that costs for public transports in Sweden in recent years have increased more than supply. Therefore, the aim of the present study is to test and evaluate the importance of the nine previously identified cost drivers (Camén & Lidestam, 2016) of public bus transports in Sweden. A mixed-method design, which included both focus groups and a questionnaire, was used. The questionnaire, with quantitative rating scales, was sent to representatives from the bus operators and from the Public Transport Authorities (PTAs). In the focus groups, industry associations, consultants, and politicians also participated. The results reveal what the dominating cost factors are, as well as the factors considered to be the most important, according to actors within the Swedish bus transport sector. The most important cost driver identified is peak traffic and the costs of its consequences.

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