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  • 1051. Breen, Jeanne
    Reducing traffic injuries in EU countries: A strategic approach1996Report (Other (popular science, discussion, etc.))
  • 1052. Breithaupt, Ute
    Driven out, sent off. Results of an investigation in the influence of the increasing number of cars and the danger from traffic on the freedom of movement of children on the streets1994Report (Other (popular science, discussion, etc.))
  • 1053. Brenner, MF
    et al.
    Frost, U
    Safety risks at traffic light installations2001Report (Other (popular science, discussion, etc.))
    Abstract [sv]

    As a consequence of growing traffic density in urban areas, time and vehicle

    actuated traffic controls are more and more often used. This paper presents a

    research in which flexible traffic light controls were examined for possible

    safety deficits. It was necessary to prove the following theory: it is

    suspected in the case of microscopic light control programs with flexible

    green periods that there is a higher safety risk, in comparison to fixed-time

    control for drivers who have local road knowledge during the change of

    signals (from yellow to red). An unexpected red light or a denied green at an

    "All-Signals-Red-At-Once-Green" -light could lead to unexpected reactions of

    the road user. Possible conflict situations are emergency braking, rear-end

    collisions and running the red light. To compare flexible controlled and

    fixed-time controlled intersections, these types of conflict were analysed.

    The investigation contained a selection of traffic light controlled

    intersections in several German cities (e. g. Stuttgart, Würzburg and Aalen).

    The study encompassed two intersections with fixed-time control, ten

    intersections with traffic-actuated control and three intersections with

    "All- Signals-Red-At-Once-Green" control. In a second measuring series at two

    intersections in Bremen, different control methods were tested under

    identical local conditions: fixed time control, semi-vehicle-actuated control

    and fully traffic-actuated control.

  • 1054. Brilon, Werner
    et al.
    Blanke, Harald
    Traffic safety effects from traffic calming1990Report (Other (popular science, discussion, etc.))
  • 1055.
    Brinck, Carl Erik
    Statens Väginstitut.
    Benefits of increased axle loads: method of calculation and its application to Swedish conditions1968Report (Other academic)
  • 1056.
    Brinck, Carl Erik
    Statens Väginstitut.
    Optimalt axeltryck1966Report (Other academic)
  • 1057. Brinkebäck, Gunnar
    Möjligheter för entreprenörer1993Report (Other (popular science, discussion, etc.))
  • 1058. Brinks, Jan
    Traffic related knowledge, attitudes and risk perception in Dutch secondary school children: Consequences for traffic education1990Report (Other (popular science, discussion, etc.))
  • 1059.
    Brodin, A
    Swedish National Road and Transport Research Institute.
    Program for the Monte Carlo simulation of vehicle traffic along two-lane rural roads1980Report (Other academic)
  • 1060.
    Brodin, A
    Swedish National Road and Transport Research Institute.
    Statistik över fordonsskador: Jämförelse mellan olika statistikkällor samt beskrivning av risktal: En förundersökning1977Report (Other academic)
  • 1061.
    Brodin, A
    Swedish National Road and Transport Research Institute.
    VTI Traffic simulation model: A program for the Monte Carlo simulation of vehicle traffic along two-lane rural roads: An application of JSP and SIMULA-67 language1983Report (Other academic)
  • 1062.
    Brodin, A
    et al.
    Swedish National Road and Transport Research Institute.
    Carlsson, A
    Swedish National Road and Transport Research Institute.
    Bolling, Anne
    Swedish National Road and Transport Research Institute.
    VTI trafiksimuleringsmodell. Del I: Beskrivning av modell och programsystem. Del II. Bilaga 1: Programsystem och exempel på utdata. Bilaga 2: Lathund för simuleringsprogrammen (The VTI traffic simulation model)1982Report (Other academic)
  • 1063.
    Brodin, A
    et al.
    Swedish National Road and Transport Research Institute.
    Gynnerstedt, G
    Swedish National Road and Transport Research Institute.
    Levander, G
    Swedish National Road and Transport Research Institute.
    Program for the Monte Carlo simulation of vehicle traffic along two-lane rural roads: An application of structured programming technique and SIMULA-67 language1979Report (Other academic)
  • 1064.
    Brodin, A
    et al.
    Swedish National Road and Transport Research Institute.
    Nilsson, G
    Swedish National Road and Transport Research Institute.
    Pettersson, H-E
    Swedish National Road and Transport Research Institute.
    Rumar, K
    Swedish National Road and Transport Research Institute.
    Planprojekt - korsningar i plan mellan järnväg och väg: Preliminärt förslag till FoU-program 1976-1978 utarbetat vid VTI på uppdrag av plankorsningsdelegationen1976Report (Other academic)
  • 1065.
    Brodin, A
    et al.
    Swedish National Road and Transport Research Institute.
    Pettersson, H-E
    Swedish National Road and Transport Research Institute.
    Trafiksäkerhetsproblem i plankorsningar mellan järnväg och väg: En litteraturstudie1978Report (Other academic)
  • 1066.
    Brodin, A
    et al.
    Swedish National Road and Transport Research Institute.
    Ringhagen, L
    Swedish National Road and Transport Research Institute.
    Effekt på olyckor och hastigheter av hastighetsgränsen 30 km/h i bostadsområden1975Report (Other academic)
  • 1067.
    Brodin, A
    et al.
    Swedish National Road and Transport Research Institute.
    Roosmark, P-O
    Swedish National Road and Transport Research Institute.
    Statistik över resor: En förundersökning1976Report (Other academic)
  • 1068.
    Brodin, A
    et al.
    Swedish National Road and Transport Research Institute.
    Thunberg, B
    Swedish National Road and Transport Research Institute.
    Utveckling av transportstatistik för beredskapsåtgärder inom området väg- och gatutrafik: Behovsanalys och program1976Report (Other academic)
  • 1069.
    Brodin, Anders
    et al.
    Swedish National Road and Transport Research Institute.
    Palaniswamy, SP
    Indo-Swedish traffic simulation model: A program for the Monte Carlo simulation of heterogeneous vehicle traffic along single lane, intermediate lane and narrow two lane roads: An application of JSP and SIMULA- 67 language1985Report (Other academic)
  • 1070.
    Brolin, Karin
    et al.
    Chalmers University of Technology.
    Östh, Jonas
    Chalmers University of Technology.
    Svensson, Mats
    Chalmers University of Technology.
    Sato, Fusako
    Japan Automotive Research Institute.
    Ono, Koshiro
    Japan Automotive Research Institute.
    Linder, Astrid
    Swedish National Road and Transport Research Institute, Traffic and road users, Traffic safety, society and road-user.
    Kullgren, Anders
    Folksam.
    Aiming for an average female virtual human body model for seat performance assessment in rear-end impacts2015In: The 24th ESV Conference Proceedings, 2015Conference paper (Refereed)
    Abstract [en]

    The female part of the population suffers more Whiplash Associated Disorders (WAD) in car crashes than males. Several studies have illustrated the need to consider the female population when developing and assessing the WAD prevention performance of advanced restraint systems in rear-end collisions. Presently only one crash test dummy is available, the average sized male BioRID. Recently a virtual dummy model of an average female, EvaRID, was developed and used in rear impact simulations. The results stressed the need for models representing the female part of the population, as well. Virtual crash simulations have become essential in traffic safety and with models of both an average male and female, further steps in addressing improved assessment of WAD prevention can be taken. The present paper presents a starting point of research aiming to develop an open-source average female Finite Element (FE) model with an anatomically detailed cervical spine. This paper provides a review of the literature to identify gender specific neck biomechanics and anatomical differences, followed by a review of published FE models of the cervical spine. Data on vertebral body dimensions (height, width, depth, spinal canal diameter, facet joint angles) have been compiled from biomechanical literature. Significant gender differences exist for the vertebral body depth and width, the spinal curvature in the seated posture, and the spinal stiffness and range of motion. All have the potential to influence the outcome of an impact and should be accounted for in the development of WAD prevention. The review of FE models of the cervical spine presented 17 models based on male geometry but only one model scaled to represent a female. An overview of the models are given with respect to the solver, geometry source, number of elements, and implementation of the facet joints, ligaments, and muscles. It is recommended that an average female model is developed with focus on; 1) the shape of the female vertebral body, especially the depth and width that provides less support area than for males,2) defining the spinal curvature representative of seated female volunteers who generally display less lordosis than males, 3) the dimensions of the spinal ligaments, rather than the material properties, to capture the larger range of motion and less spinal stiffness of female subjects compared to males, and validation to female volunteers and PMHS tests for range of motion, while failure prediction seem less gender sensitive.

     

     

  • 1071. Broms, H
    Dimensionering av helt bitumenbundna överbyggnader (HBÖ) enligt olika metoder1976Report (Other academic)
  • 1072.
    Bronge, I
    Swedish National Road and Transport Research Institute.
    Flexible pavements1975Report (Other academic)
  • 1073.
    Bronge, I
    Swedish National Road and Transport Research Institute.
    Planning and construction of highways1975Report (Other academic)
  • 1074.
    Bronge, I
    Swedish National Road and Transport Research Institute.
    Väg- och trafikforskare från VTI 'pryar' hos vägmästarna1979Report (Other academic)
  • 1075. Brooking, Peter
    Två flygplatser - Två planeringsprocesser: en jämförelse mellan Arlandas tredje bana och Schiphols femte bana1997Report (Other (popular science, discussion, etc.))
  • 1076. Broomfield, John P
    SHRP concrete & structures research1994Report (Other (popular science, discussion, etc.))
  • 1077.
    Broth, Mathias
    et al.
    Linköpings Universitet.
    Cromdal, Jakob
    Linköpings Universitet.
    Levin, Lena
    Swedish National Road and Transport Research Institute, Society, environment and transport, Mobility, actors and planning processes.
    Showing where you're going. Instructing the accountable use of the indicator in live traffic2018In: International Journal of Applied Linguistics, ISSN 0802-6106, E-ISSN 1473-4192, Vol. 28, no 2, p. 248-264Article in journal (Refereed)
    Abstract [en]

    This article takes an interest in how students at a driving school are instructed how to make the car's behaviour intelligible (accountable) to other road users in traffic. Taking the indicator as an example, the analytic focus is on the ways in which the indicator's relevance is instructed and its timely activation practiced, and how activating the indicator is instructed as part of more encompassing turning procedures. The indicator is one of the central resources built into cars for displaying to others a driver's intention about where to go next. Although indicating does not, in itself, affect the movement of the car, activating the indicator is crucial for allowing others to anticipate a car's movement in space, and coordinate themselves with it. The analysis shows how instructors manage trainee drivers' instructed actions during driving by providing descriptions of what using the indicator accomplishes before a directive to turn (a), after a directive to turn (b), and as accounts for initiating correction of trainee driver car control activity (c).

  • 1078.
    Broth, Mathias
    et al.
    Linköping Universitet.
    Cromdal, Jakob
    Linköping Universitet.
    Levin, Lena
    Swedish National Road and Transport Research Institute, Society, environment and transport, Mobility, actors and planning processes.
    Telling the Other's side. Formulating others' mental states in driver training2018In: Language & Communication, ISSN 0271-5309, E-ISSN 1873-3395Article in journal (Refereed)
    Abstract [en]

    This article examines ascriptions of mental states to other road users in live traffic driver training. Through this practice, instructors formulate how others make sense of the trainee driver's car. Using multimodal conversation analysis, we demonstrate how others' side formulations support trainee drivers' communicative handling of the car during ongoing coordination events. In contrast, formulations occurring after coordination events serve educational ends, yielding the generic inferential practices by which competent drivers make contextual sense of others' actions. Therefore, others' side formulations comprise an important instructional resource for introducing neophyte drivers into the real-world theorizing, rendering traffic its orderly social character.

  • 1079.
    Broth, Mathias
    et al.
    Linköping University.
    Jakob, Cromdal
    Linköping University.
    Levin, Lena
    Swedish National Road and Transport Research Institute, Society, environment and transport, Mobility, actors and planning processes.
    Starting out as a driver: Progression in instructed pedal work2017In: Memory practices and learning: Interactional, institutional and sociocultural perspectives / [ed] Mäkitalo, Åsa; Linell, Per; Säljö, Roger, IPA Publisher , 2017, p. 113-142Chapter in book (Refereed)
  • 1080. Broughton, J
    A study of causation factors in car accidents1996Report (Other (popular science, discussion, etc.))
  • 1081. Broughton, Jeremy
    A new system for recording contributory factors in road accidents1998Report (Other (popular science, discussion, etc.))
  • 1082. Broughton, Jeremy
    Restraint use by car occupants, Great Britain 1982-911991Report (Other (popular science, discussion, etc.))
  • 1083. Brouwer, Martha
    Road safety information system: Key information supporting traffic safety policy in the Netherlands1998Report (Other (popular science, discussion, etc.))
  • 1084.
    Brown, David B
    et al.
    The University of Alabama, USA.
    Turner, Daniel S
    The University of Alabama, USA.
    The Critical Analysis Reporting Environment (CARE): a versatile tool to obtain optimal accident countermeasure strategies2001In: Proceedings of the conference Road Safety on Three Continents: International conference in Pretoria, South Africa, 20-22 September 2000 / [ed] Asp, Kenneth, Linköping: Statens väg- och transportforskningsinstitut, 2001, p. 148-161Conference paper (Other academic)
    Abstract [en]

    The Crash Analysis Reporting Environment is a sophisticated crash record analysis system that is powerful, highly versatile and easily transportable. It was designed specifically to review accident data and to provide user-friendly summaries and reports on topics defined in real time by the user. CARE operates on a desktop computer using the Windows or NT system. It is in the public domain and can easily be downloaded (http://care.cs.ua.edu). With simple modifications it can be mated to virtually any crash record database. The paper presents features of the analysis system together with several examples.

  • 1085. Brown, James L
    Future pavement performance research data needs for Texas1990Report (Other (popular science, discussion, etc.))
  • 1086. Brown, James L
    The LTPP experiment of SHRP: An envolving process1988Report (Other (popular science, discussion, etc.))
  • 1087. Brown, SF
    et al.
    Cooper, KE
    Simplified methods for determination of fundamental material properties of asphalt mixes1994Report (Other (popular science, discussion, etc.))
  • 1088. Brownfield, John
    et al.
    Faber, Oscar
    The application of safety audit principles as a means of accident prevention1996Report (Other (popular science, discussion, etc.))
  • 1089. Brule, Bernhard
    et al.
    Maze, Michel
    Application d'essais developpes par le SHRP caracterisation de bitumes-polymeres/Application of SHRP-developed tests to the characterization of polymer-modified bitumens1995Report (Other (popular science, discussion, etc.))
  • 1090.
    Brundell-Freij, Karin
    et al.
    WSP Analysis & Strategy.
    Jonsson, Lina
    Swedish National Road and Transport Research Institute, Society, environment and transport, Transport economics Stockholm.
    Källström, Jenny
    WSP Analysis & Strategy.
    Accepting charging: a matter of trusting the effects?2009Conference paper (Other academic)
    Abstract [en]

    The public typically considers urban congestion to be a serious problem. In the scientific community it is considered basic knowledge that pricing is often the only effective way to mitigate such congestion. However, implementation of congestion charging continues to meet hard resistance from the public, and politicians continue to rule out that policy option referring to lack of public acceptance. Many authors have explained the paradox by the public?s (layman) suspicion that charging would not be effective and not reduce congestion. From a number of implemented schemes, we also know that once they have experience from (the effects of) charging, the public tend to change to more positive, which seems to support the hypothesis that lack of experience and erroneous subjective predictions of effects causes ?the problem?.

    To analyse the hypothesized causal link this study explores how the (i)attitudes towards congestion charging in Stockholm and (ii)the expectancy/understanding of the effects of charging (co-)varied over time and between individuals in the Stockholm public during different phases of the implementation process: before (autumn 2005) and during the Trial (spring 2006), and after permanent introduction of charging (autumn 2007).

    For the analyses, we have employed ordinal logit models. This allows us to draw conclusions on the simultaneous relation(s) between acceptance on one hand and individual background characteristics, personal experience and understanding of effects on the other. One of the many advantages with the analytical approach employed is that it allows us to control for, for example, car ownership in the analyses of gender differences in attitudes and predicted effects ? which has given new insights compared to the one-dimensional analyses presented earlier.

    A brief summary of results: The differences between men and women in attitudes and understanding of congestion charging are negligible when difference in car availability is taken into account. The frequently discussed difference between inner city inhabitants and people living in the regional periphery, too, turns out to be largely explained by differences in car ownership.

    When experience is gained, people do indeed trust that charging mitigates congestion to a higher extent than they did before: Those that agree that ?congestion charges will decrease [have decreased] the queues to and from the inner-city? is a significantly larger proportion of the population during the Trial, than they were before. Also in accordance with previous results, the attitudes towards the charges became more positive after introduction. This was a continuous process over time, so that attitudes were more positive during the Trial than before, and even more positive after permanent introduction than they were during the Trial. However, the results clearly show that the change in attitudes was much stronger, and continued over a longer period of time, than what could be explained by the learning effect leading to a better understanding of the effects on congestion.

    Thus, based on our results, our understanding of which the influential factors are behind the observed effect from experience on attitudes to charging, has to be modified. The mechanisms clearly go beyond ?demonstrating? that charging may effectively mitigate congestion, which is the reason most commonly given in the literature so far.

    Our results have important policy implications for which arguments that can be expected to be most effective in building public acceptance for charging, and which subpopulations that are most likely to be influenced by such argumentation.

  • 1091.
    Bruzelius, Fredrik
    Swedish National Road and Transport Research Institute, Traffic and road users, Vehicle technology and simulation. Chalmers Tekniska Högskola.
    A theoretical justification of the sine with dwell manoeuvre2015In: Vehicle System Dynamics, ISSN 0042-3114, E-ISSN 1744-5159, Vol. 53, no 4, p. 493-505Article in journal (Refereed)
    Abstract [en]

    The sine with dwell (SWD) manoeuvre has received much attention within the context of vehicle stability testing. This manoeuvre is used in a test developed by the NHTSA, designed to certificate electronic stability control systems in light vehicles. The test is used in legislations as well as in consumer tests all over the globe. The SWD manoeuvre was designed using test vehicles on a test track and experimentally validated. The paper at hand uses optimal control theory to theoretically justify the use of the SWD manoeuvre to produce a severe lateral motion and over-steering based on steering input. It is shown that a manoeuvre similar to the SWD manoeuvre can be obtained from an optimal control problem using simple vehicle dynamics models. The optimal control method is further used to analyse the manoeuvre's robustness with respect to vehicle dimensions and tyre properties. It is shown that the manoeuvre is robust in dimensions, which theoretically motivates its application for various sizes of vehicles.

  • 1092.
    Bruzelius, Fredrik
    Swedish National Road and Transport Research Institute, Traffic and road users, Vehicle technology and simulation.
    Specifications list2010Report (Other academic)
    Abstract [en]

    eVALUE is addressing active safety functions and their capability to perform through two courses of action: defining and quantifying the requirements of a safety function under a relevant traffic accident scenario and developing the testing and evaluation methods for the active safety functions of vehicles. WP2 aims at developing testing procedures based on the system descriptions and scenarios defined in WP1. The testing procedures will be integrated in WP3 and finally carried out and assessed in WP4. D2.2 takes the output of D2.1 and, where scenarios, safety functions and test procedures are related, defines the basis for the test procedures further developed in the next work packages. The test procedures are drafted, taking into account the future “testing protocols” and the “assessment protocols”. The document is structured according to the scheme followed from the project start, where tests are classified into “Design Reviews”,”Physical Testing” and “Laboratory Testing”. The test procedures are also classified depending on clustering different safety functions: “Longitudinal Assistance”, “Lateral Assistance” and “Stability”.

  • 1093.
    Bruzelius, Fredrik
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Vehicle technology and simulation. Chalmers Tekniska Högskola.
    Gomez Fernandez, Jorge
    Chalmers Tekniska Högskola.
    Augusto, Bruno
    Swedish National Road and Transport Research Institute, Traffic and road users, Vehicle technology and simulation.
    A Basic Vehicle Dynamics Model for Driving Simulators2013In: International Journal of Vehicle Systems Modelling and Testing, ISSN 1745-6436, Vol. 8, no 4, p. 364-385Article in journal (Refereed)
    Abstract [en]

    Driving simulators are a useful research tool in studies of vehicle and transport-related human machine interface. A vital part of the driving simulator is the vehicle dynamics model. In the present paper, such a model is developed. The model implements basic first order phenomena, but is yet complete in the terms of modelled parts of the vehicle. A major challenge is the trade-off between simplicity and accuracy imposed by the capabilities of the driving simulators motion platform. The modelling language Modelica was used for readability reasons. The model has been validated toward both measurements of a real car and subjectively in a driving simulator. It is shown that the model is well capable of fulfilling the imposed requirements, despite its simplicity. The model is open and available upon request.

  • 1094.
    Bruzelius, Fredrik
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Vehicle technology and simulation.
    Hjort, Mattias
    Swedish National Road and Transport Research Institute, Traffic and road users, Vehicle technology and simulation.
    Andersson, Håkan
    Swedish National Road and Transport Research Institute, Infrastructure, Crash safety.
    Towards an Indoor Winter Tire Classification Test2012In: Proceedings of VSDIA 2012, 2012Conference paper (Refereed)
    Abstract [en]

    From a traffic safety perspective it is highly motivated to define winter tires interms of their performance in icy road conditions. The present definition of winter(snow) tires, introduced in the EU in 2012, is based on packed snow performance.The present paper investigates the feasibility of an indoor winter tire classificationtest on ice. Results presented here indicates that a test procedure in an indoorhockey rink is possible, with relatively high repeatability. However, further fieldtest is required to fully establish feasibility of the procedure.

  • 1095.
    Bruzelius, Fredrik
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Vehicle technology and simulation.
    Hjort, Mattias
    Swedish National Road and Transport Research Institute, Traffic and road users, Vehicle technology and simulation.
    Svendenius, Jacob
    BorgWarner TTS.
    Validation of a basic combined slip tyre model for use in friction estimation applications2014In: Proceedings of the Institution of mechanical engineers. Part D, journal of automobile engineering, ISSN 0954-4070, E-ISSN 2041-2991, Vol. 228, no 13, p. 1622-1629Article in journal (Refereed)
    Abstract [en]

    Tyre modelling is an important part of understanding and estimating the tyre-road friction. In this paper a basic steady-state tyre model for the combined-slip case is derived. The model is intended to be used in friction estimations applications, where the model complexity is of high priority. The model, described using only two parameters, is validated with measured data from various conditions and tyre types using mobile measurement equipment. The performance from the measurements suggests that only two parameters are sufficient for the combined-slip case.

  • 1096.
    Bruzelius, Fredrik
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Vehicle technology and simulation. Chalmers Tekniska Högskola.
    Karlsson, MariAnne
    Chalmers Tekniska Högskola.
    Augusto, Bruno
    Swedish National Road and Transport Research Institute, Traffic and road users, Vehicle technology and simulation.
    Realism of overtaking situations in motion based driving simulators2013Conference paper (Refereed)
    Abstract [en]

    The credibility of the research results of driving simulator studies is highly dependent on the realism that the simulator is capable of producing. A key component is therefore how realistic the driving is perceived by the drivers (test subjects). Overtaking is a frequently occurring traffic situation (as well as one of the highest risk manoeuvres). The aim of the present study was to enhance the perceived realism of overtaking situations in a motion-based driving simulator by introduce aerodynamic forces and moments. An earlier developed real time model of the aerodynamic forces and moments was been implemented and tested in a study with test drivers.With an appropriate scaling of the forces and torques it was shown that the perceived realism can be enhanced by the introduction of these effects.

  • 1097.
    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.

  • 1098.
    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.  

  • 1099.
    Bruzelius, Fredrik
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Vehicle technology and simulation.
    Svendenius, Jacob
    Haldex Brake Products.
    Yngve, Simon
    SAAB Automobile.
    Casselgren, Johan
    Volvo Technology.
    Rönnberg, Johan
    Volvo cars cooporation.
    Olsson, Gunnar
    Optical Sensors.
    Evaluation of Tire to Road Friction Estimators, Test Methods and Metrics2010In: International Journal of Vehicle Systems Modelling and Testing, ISSN 1745-6436, Vol. 5, no 2/3, p. 213-236Article in journal (Refereed)
    Abstract [en]

    The tyre to road contact friction is one of the most important properties when it comes to manoeuvrability of ground vehicles and information, to driver and vehicle, is of vital importance in critical situations. Different characteristics of different friction estimation methods make it hard to determine and compare performance of estimators. This article is an attempt to define and evaluate the performance of tyre to road friction estimators. The objective of the performance evaluation is to define and grade the performance of estimators based on all sorts of approaches and combinations of these. The result may be used in the context of benchmarking as well as a tool in the development process of the estimator. The test methods and metrics presented are illustrated with a comparative study of three different estimation approaches

  • 1100.
    Bruzelius, Fredrik
    et al.
    Chalmers Tekniska Högskola.
    Uystepruyst, David
    Chalmers Tekniska Högskola.
    Jacobson, Bengt
    Chalmers Tekniska Högskola.
    Krajnovi´c, Sinisa
    Chalmers Tekniska Högskola.
    A simple real-time aerodynamic model for vehicles in overtaking situations2013In: International Journal of Vehicle Systems Modelling and Testing, ISSN 1745-6436, Vol. 8, no 3, p. 241-259Article in journal (Refereed)
    Abstract [en]

    Aerodynamic forces and moments play an important role inovertaking situations and affect the trajectory of the involved vehicles. One method of studying these effects and how the driver responds to these is via driving simulator studies. However, models that describe aerodynamic forces and moments are typically computationally complex and not suited for real time execution in driving simulators. The present work presents a simplified real time model of the moments and forces acting in an overtaking situation due to aerodynamic pressure imbalances. The model is compared with experimentally validated Navier-Stokes solutions. Despite the model’s simplicity, implemented as finite impulse response filters, it manages to capture the main features of the forces and moments. The approach used to derive the model is fairly general and might be used in similar applications where computational burden is a key issue.

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