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  • 1.
    Adell, Emeli
    et al.
    Trivector Traffic.
    Nilsson, Annika
    Trivector Traffic.
    Kircher, Katja
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Cyclists' use of mobile IT in Sweden: usage and self-reported behavioural compensation2014In: 3rd International Cycling Safety Conference (ICSC2014), 18-19 November, Gothenburg, Sweden: proceedings, Gothenburg, Sweden, 2014Conference paper (Refereed)
    Abstract [en]

    The increasing use of mobile phones while cycling has raised safety concerns. In this paper two studies of mobile phone use by cyclists are presented.

    The first study was designed to characterize mobile phone use by cyclists in Sweden, while the second studied how mobile phone use affected cyclist behaviour and compensation strategies. Mobile phone use was observed in about 20 percent of all urban bicycle trips. The usage varied with cyclist age with the highest usage among young cyclists. Of those using phones, 90% of the cyclists observed used head-phones.

    In parallel, standardized, interviews 15% of cyclists under 15 years old stated that they always used mobile phones while cycling. Listening to music in headphones was the most fre-quent self-reported activity. To converse using hand-held phones was also rather common, and was the only mobile phone usage reported by women above 50 years old.

    In the second study twenty-two young cyclists (age 16-25 years) completed a route in real traffic five times while listening to music, receiving and making calls, receiving and sending text messages, searching for information on the internet and while cycling normally without using the phone. The route and the types of tasks were controlled, but the cyclists could choose rather freely when, where and how to carry out the tasks. When the cyclist returned to the starting point, a short interview was conducted. During the interviews cyclists reported their experiences and the compensation strategies they used while cycling.

  • 2.
    Ahlström, Christer
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Fors, Carina
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Forward, Sonja
    Swedish National Road and Transport Research Institute, Society, environment and transport, Mobility, actors and planning processes.
    Gregersen, Nils Petter
    Swedish National Road and Transport Research Institute, Society, environment and transport, Mobility, actors and planning processes.
    Hjälmdahl, Magnus
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Jansson, Jonas
    Swedish National Road and Transport Research Institute, Traffic and road users.
    Kircher, Katja
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Lindberg, Gunnar
    Swedish National Road and Transport Research Institute, Society, environment and transport, Transport economics Stockholm.
    Nilsson, Lena
    Swedish National Road and Transport Research Institute, Traffic and road users.
    Patten, Christopher
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Dangerous use of mobile phones and other communication devices while driving: A toolbox of counter-measures2013In: Proceedings of the 16th International Conference Road Safety on Four Continents: Beijing, China. 15-17 May 2013, Linköping: Statens väg- och transportforskningsinstitut, 2013Conference paper (Other academic)
    Abstract [en]

    The use of mobile phone and similar devices while driving has been a topic of discussion and research for several years. It is now an established fact that driving performance is deteriorated due to distraction but no clear conclusions can yet be drawn concerning influence on crash rates. Better studies on this relationship is needed. Most countries in Europe and many countries elsewhere have introduced different types of bans for handheld devices. Sweden has, however, no such bans. VTI was commissioned by the Swedish Government to outline possible means to reduce the dangerous usage of mobile phones and other communication devices while driving as alternatives to banning. This task was a result of a previous VTI-state-of-the-art review of research on mobile phone and other communication device usage while driving. One of the findings in the review was that bans on handheld phones did not appear to reduce the number of crashes.

    Eighteen different countermeasures in three main areas were suggested. (1) Technical solutions such as countermeasures directed towards the infrastructure, the vehicle and the communication device. (2) Education and information, describing different ways to increase knowledge and understanding among stakeholders and different driver categories. (3) Different possibilities for how society, industry and organisations can influence the behaviour of individuals, via policies, rules, recommendations and incentives. Our conclusion is that a combination of different countermeasures is needed – where education and information to the drivers are combined with support and incentives for a safe usage of different communication devices.

  • 3.
    Ahlström, Christer
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Trafikanttillstånd, TIL.
    Ihlström, Jonas
    Swedish National Road and Transport Research Institute, Traffic and road users, Trafikanttillstånd, TIL.
    Kircher, Katja
    Swedish National Road and Transport Research Institute, Traffic and road users, Trafikanttillstånd, TIL.
    Förares användning av kommunikationsutrustning under färd: Del 1: Enkätstudie. Del 2: Användning enligt objektiv mätning2017Report (Other academic)
    Abstract [sv]

    Av resultaten från denna enkät är något av det mest tydliga att saker som funnits i en bil en längre tid, exempelvis att ställa in radio, använda navigationsutrustning och prata i telefon, görs i betydligt högre utsträckning än nyare saker som att skicka meddelanden, surfa på internet eller spela spel. Överlag tycks det vara låg acceptans för de nyare företeelserna och en stor andel av urvalet tycker att det är felaktigt eller olämpligt att hålla på med dessa aktiviteter. Att prata i telefon med handsfree tycks uppfattas av många som säkrare och mer lämpligt än att inte använda det. Detta avspeglas även i inställning till införandet av förbud, där en relativt stor andel accepterar att det ska vara lagligt att använda handsfreefunktioner men att annan användning av kommunikationsutrustning borde förbjudas.

    I den andra delen genomfördes en mätning av mobilanvändning under färd genom installerande tav en mobilapp. Den genomförda undersökningen är den första av sitt slag åtminstone i Sverige, så att den, trots vissa brister och begränsningar, kan leverera information som hittills har varit okänt. I detta del diskuteras resultaten, även i förhållande till enkätsvaren, följt av en reflektion över metoden och möjliga förbättringar, som är önskvärda inför en fortsättningsstudie.

  • 4.
    Ahlström, Christer
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Human Factors in the Transport System.
    Kircher, Katja
    Swedish National Road and Transport Research Institute, Traffic and road users, Human Factors in the Transport System. Linköpings Universitet.
    A Generalized Method to Extract Visual Time-Sharing Sequences From Naturalistic Driving Data2017In: IEEE transactions on intelligent transportation systems (Print), ISSN 1524-9050, E-ISSN 1558-0016, Vol. 18, no 11, p. 2929-2938Article in journal (Refereed)
    Abstract [en]

    Indicators based on visual time-sharing have been used to investigate drivers' visual behaviour during additional task execution. However, visual time-sharing analyses have been restricted to additional tasks with well-defined temporal start and end points and a dedicated visual target area. We introduce a method to automatically extract visual time-sharing sequences directly from eye tracking data. This facilitates investigations of systems, providing continuous information without well-defined start and end points. Furthermore, it becomes possible to investigate time-sharing behavior with other types of glance targets such as the mirrors. Time-sharing sequences are here extracted based on between-glance durations. If glances to a particular target are separated by less than a time-based threshold value, we assume that they belong to the same information intake event. Our results indicate that a 4-s threshold is appropriate. Examples derived from 12 drivers (about 100 hours of eye tracking data), collected in an on-road investigation of an in-vehicle information system, are provided to illustrate sequence-based analyses. This includes the possibility to investigate human-machine interface designs based on the number of glances in the extracted sequences, and to increase the legibility of transition matrices by deriving them from time-sharing sequences instead of single glances. More object-oriented glance behavior analyses, based on additional sensor and information fusion, are identified as the next future step. This would enable automated extraction of time-sharing sequences not only for targets fixed in the vehicle's coordinate system, but also for environmental and traffic targets that move independently of the driver's vehicle.

  • 5.
    Ahlström, Christer
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Trafikanttillstånd, TIL.
    Kircher, Katja
    Swedish National Road and Transport Research Institute, Traffic and road users, Trafikanttillstånd, TIL. Linköping University.
    Changes in glance behaviour when using a visual eco-driving system: A field study2017In: Applied Ergonomics, ISSN 0003-6870, E-ISSN 1872-9126, Vol. 58, p. 414-423Article in journal (Refereed)
    Abstract [en]

    While in-vehicle eco-driving support systems have the potential to reduce greenhouse gas emissions and save fuel, they may also distract drivers, especially if the system makes use of a visual interface. The objective of this study is to investigate the visual behaviour of drivers interacting with such a system, implemented on a five-inch screen mounted above the middle console. Ten drivers participated in a real-world, on-road driving study where they drove a route nine times (2 pre-baseline drives, 5 treatment drives, 2 post-baseline drives). The route was 96 km long and consisted of rural roads, urban roads and a dual-lane motorway.

    The results show that drivers look at the system for 5–8% of the time, depending on road type, with a glance duration of about 0.6 s, and with 0.05% long glances (>2s) per kilometre. These figures are comparable to what was found for glances to the speedometer in this study. Glance behaviour away from the windscreen is slightly increased in treatment as compared to pre- and post-baseline, mirror glances decreased in treatment and post-baseline compared to pre-baseline, and speedometer glances increased compared to pre-baseline. The eco-driving support system provided continuous information interspersed with additional advice pop-ups (announced by a beep) and feedback pop-ups (no auditory cue). About 20% of sound initiated advice pop-ups were disregarded, and the remaining cases were usually looked at within the first two seconds. About 40% of the feedback pop-ups were disregarded. The amount of glances to the system immediately before the onset of a pop-up was clearly higher for feedback than for advice.

  • 6.
    Ahlström, Christer
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Kircher, Katja
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Review of real-time visual driver distraction detection algorithms2011In: ACM International Conference Proceeding Series, 2011Conference paper (Refereed)
    Abstract [en]

    Many incidents and crashes can be attributed to driver distraction, and it is essential to learn how to detectdistraction in order to develop efficient countermeasures. A number of distraction detection algorithms have been developed over the years, and the objective of this paper is to summarize available approaches and to describe these algorithms in a unified framework. The review is limited to real-time algorithms that are intended to detect visual distraction.

  • 7.
    Ahlström, Christer
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Kircher, Katja
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Fors, Carina
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Dukic, Tania
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Patten, Christopher
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Anund, Anna
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Measuring driver impairments: Sleepiness, distraction, and workload2012In: IEEE Pulse, ISSN 2154-2287, Vol. 3, no 2, p. 22-30Article in journal (Refereed)
    Abstract [en]

    Snow was falling heavily when Sarah was driving on a slippery road to her cousin’s country cottage. It was dark outside, and the visibility was poor. She had planned to arrive before sunset, but the rental service had made a mistake, and it took hours before she got her rental car at the airport. It was past midnight now, and after a long day of traveling, Sarah was starting to get sleepy.

    Fortunately, there were only 15 km to go, but her eyelids were starting to feel heavy. To stay awake, she put her favorite CD on, turned up the volume, and started to sing along. This seemed to help a little -good- only 10 km to go. This was when Sarah’s phone started ringing, and she awkwardly tried to find the mute button for the car stereo while answering the phone. As she looked up again, she barely caught a glimpse of the red brake lights of the car in front of her as she smashed into it.

  • 8.
    Ahlström, Christer
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Kircher, Katja
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Kircher, Albert
    Linköpings Universitet.
    A gaze-based driver distraction warning system and its effect on visual behaviour2013In: IEEE transactions on intelligent transportation systems (Print), ISSN 1524-9050, E-ISSN 1558-0016, Vol. 14, no 2, p. 965-973Article in journal (Refereed)
    Abstract [en]

    Driver distraction is a contributing factor to many crashes; therefore, a real-time distraction warning system should have the potential to mitigate or circumvent many of these crashes. The objective of this paper is to investigate the usefulness of a real-time distraction detection algorithm called AttenD. The evaluation is based on data from an extended field study comprising seven drivers who drove on an average of 4351 ± 2181 km in a naturalistic setting.

    Visual behavior was investigated both on a global scale and on a local scale in the surroundings of each warning. An increase in the percentage of glances at the rear-view mirror and a decrease in the amount of glances at the center console were found. The results also show that visual time sharing decreased in duration from 9.94 to 9.20 s due to the warnings, that the time from fully attentive to warning decreased from 3.20 to 3.03 s, and that the time from warning to full attentiveness decreased from 6.02 to 5.46 s. The limited number of participants does not allow any generalizable conclusions, but a trend toward improved visual behavior could be observed. This is a promising start for further improvements of the algorithm and the warning strategy.

  • 9.
    Ahlström, Christer
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Kircher, Katja
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Kircher, Albert
    Swedish National Road and Transport Research Institute, Traffic and road users, Vehicle technology and simulation.
    Considerations when calculating percent road centre from eye movement data in driver distraction monitoring2009In: Proceedings of the Fifth International Driving Symposium on Human Factors in Driver Assessment, Training and Vehicle Design, 2009, p. 132-139Conference paper (Refereed)
    Abstract [en]

    Percent road center (PRC) is a performance indicator which is sensitive to driver distraction. The original definition of PRC is based on fixation data extracted from eye movement recordings, but it has also been suggested that PRC can be determined directly from the gaze data without segmenting it into saccades and fixations. The primary aim of this paper is to investigate if this is the case.

    Naturalistic driving data from a small scale field operational test comprising seven vehicles was used in the evaluation. It was found that PRC time traces based on gaze data and fixation data, respectively, were highly similar (correlation coefficient=0.95, average wavelet semblance=0.84) except for an absolute amplitude difference of about 8%. This indicates that the two approaches can be used interchangeably and that the processing step of segmenting gaze data into saccades and fixations can be left out.

    In addition to this finding, design issues related to the calculation of PRC are investigated. Especially, the impact of gaze cases pointing towards the intersection of the road centre area and the centre rear mirror were investigated. Results lead to conclude that gazes and fixations on the centre rear mirror should be removed from the PRC calculations, as they may negatively influence the correctness of the performance indicator.

  • 10.
    Ahlström, Christer
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Kircher, Katja
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Rydström, Annie
    Volvo Car Corperation.
    Nåbo, Arne
    SAAB Automobile.
    Almgren, Susanne
    SAAB Automobile.
    Ricknäs, Daniel
    Scania.
    Effects of visual, cognitive and haptic tasks on driving performance indicators2012In: Advances in Human Aspects of Road and Rail Transportation / [ed] Neville A . Stanton, San Francisco, USA: CRC Press , 2012, p. 673-682Conference paper (Refereed)
  • 11.
    Ahlström, Christer
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Kircher, Katja
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Thorslund, Birgitta
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Adell, Emeli
    Trivector Traffic.
    Bicyclists’ visual strategies when conducting self-paced vs. system-paced smartphone tasks in traffic2015In: Transportation Research Part F: Traffic Psychology and Behaviour, ISSN 1369-8478, E-ISSN 1873-5517, Vol. 41, p. 204-216Article in journal (Refereed)
    Abstract [en]

    Visual distraction among cyclists interacting with their mobile phones is a growing concern. Yet, very little research has actually investigated how cyclists apply visual strategies and adapt task execution depending on the traffic situation. The aim of this study is to investigate visual behaviour of cyclists when conducting self-paced (initiated by the cyclist) vs. system-paced (initiated by somebody else) smartphone tasks in traffic. Twenty-two cyclists completed a track in real traffic while listening to music, receiving and making calls, receiving and sending text messages, and searching for information on the internet. The route and the types of tasks were controlled, but the cyclists could choose rather freely when and where along the route to carry out the tasks, thus providing semi-naturalistic data on compensatory behaviour. The results show that the baseline and music conditions were similar in terms of visual behaviour. When interacting with the phone, it was found that glances towards the phone mostly came at the expense of glances towards traffic irrelevant gaze targets and also led to shortened glance durations to traffic relevant gaze targets, while maintaining the number of glances. This indicates that visual “spare capacity” is used for the execution of the telephone tasks. The task type influenced the overall task duration and the overall glance intensity towards the phone, but not the mean nor maximum duration of individual glances. Task pacing was the factor that influenced visual behaviour the most, with longer mean and maximum glance durations for self-paced tasks. In conclusion, the cyclists used visual strategies to integrate the handling of mobile phones into their cycling behaviour. Glances directed towards the phone did not lead to traffic relevant gaze targets being missed. In system-paced scenarios, the cyclists checked the traffic more frequently and intensively than in self-paced tasks. This leads to the assumption that cyclists prepare for self-initiated tasks by for example choosing a suitable location. Future research should investigate whether these strategies also exists amongst drivers and other road user groups.

  • 12.
    Anund, Anna
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Eriksson, Lars
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Kircher, Katja
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Strand, Lennart
    Mälardalens högskola.
    Porathe, Thomas
    Mälardalens högskola.
    Utveckling och prövning av ny skolskjutsskylt2010Report (Other academic)
    Abstract [en]

    In connection with boarding and alighting bus passengers are exposed to risks caused by other traffic. Children are especially vulnerable when traveling to and from school, and there are strong reasons for urging the vehicles passing a stationary school transport to reduce their speed significantly. Based on the experience of a previous project it was decided to propose the imposition of a limit of 30 km/h when there is a stationary school transport throughout the country on roads with speed limits of 70 km/h and less. In connection with a change of the traffic regulations it is important to create a school bus sign that is respected by all road users. The purpose of this study is to develop and test a school bus sign that has a high degree of conspicuity, and can be detected and read from an adequate distance. Most important, it has to be understood and respected. The study results will provide a basis for a set of requirements on a sign that should make drivers reduce their speed to 30 km/h when passing a stationary school bus. The study includes both workshops and focus groups with various stakeholders, one indoor and one outdoor lab experiment, and a field test. The results from the sub-studies lead to a recommendation to use a VMS-type sign that includes motion, which is more conspicuous than signs with a static symbol. It is expected that the final version of a digital sign will have a similar or better conspicuity and legibility than the traditional bus sign, which should increase compliance. Furthermore, it is likely that compliance with the new speed regulation will be improved when drivers not only are informed about the potential hazard source - children - but when they, too, are informed about the appropriate action - a speed reduction to 30 km/h.

  • 13.
    Anund, Anna
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Kircher, Katja
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Advantages and disadvantages of different methods to evaluate sleepiness warning systems2009Report (Other academic)
    Abstract [en]

    This is a methodological paper with the aim to discuss pros and cons related to different tools and environments when evaluating the effect of warnings given to sleepy drivers. There is no simple answer to the question which platform is most suitable. It depends on the research question asked, and it is possible that different aspects of the problem should be approached with different methods. A driving simulator has clear advantages when high control and repeatability are paramount. A simulator can also be used when the driver has to be put into a potentially dangerous scenario. How ecologically valid the results obtained from a simulator in fact are depends very much on the fidelity of the simulator. A test track study is based on real driving and should have a higher degree of ecological validity. On the other hand, the test track most often consists of an unrealistic environment. For assessing the prevalence of drowsy driving in real traffic, and in order to investigate what drivers actually do when they receive a sleepiness warning, it is absolutely necessary to study their natural behaviour when they go about their daily routines. Here field operational tests or naturalistic driving studies are most suitable. A disadvantage is the lack of control.

  • 14.
    Archer, Jeffery
    et al.
    Kungliga Tekniska Högskolan.
    Vogel, Katja
    Swedish National Road and Transport Research Institute.
    The Traffic Safety Problems in Urban Areas2000Report (Other academic)
    Abstract [en]

    As the number of people who reside and work in urban areas increases, so, too, do theneeds and demands placed on the infrastructure. This has led to severe congestion in manyEuropean cities, a situation which affects not only the environment in terms of pollution,but most notably levels of traffic safety. In Europe, tens of thousands of people are killed inroad traffic accidents, and more than 1 million are injured each year at a cost, which isestimated to exceed the total European Union budget by a factor of two. The majority ofaccidents involving injury occur within urban areas often at junctions, while the number offatalities outside these areas is greater, largely as a result of higher speed. Traffic safetyresearch has shown a biased interest in the problems associated with motorway and ruralareas in the past. There are many reasons, which advocate a greater interest in urban areas,in particular, those related to the safety of unprotected road users. In urban areas the trafficsystem context is more complex, where a mixed road user environment prevails and greaterperceptual and cognitive demands are placed on road users. In the past, many of the moresuccessful safety countermeasures have focused on designing the roadway to meet theneeds and limitations of road users. These solutions have, however, proved to be verycostly. Today, new and relatively cheap technological solutions referred to as IntelligentTransport Systems (ITS) have been developed which have the capacity to reduce exposure,accident risk, and accident severity. While the long term effects of these systems are largelyunknown, and problems associated with standardisation and legislation are in need ofresolve, systems such as Intelligent Speed Adaptation and advanced traffic control systemshave shown great potential with regard to the traffic safety problem in urban areas. In orderto effectuate this potential, a great deal of integrated multi-disciplinary research is required

  • 15.
    Canovi, Luca
    et al.
    University of Modena and Reggio Emilia.
    Minin, Luca
    University of Modena and Reggio Emilia.
    Andersson, Jan
    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.
    Kircher, Katja
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Kutila, Matti
    VTT Technical Research Centre, Finland.
    Britschgi, Virpi
    VTT Technical Research Centre, Finland.
    Sachelarie, Adrian
    The Gheorghe Asachi Technical University of Iasi.
    Barsanescu, Paul
    The Gheorghe Asachi Technical University of Iasi.
    Janos, Stautz
    Clarity Consulting Info rmation and Management Services.
    Eckstein, Bernd
    Univ ersity of Stuttgart.
    Regulation knowledge presentation2010Report (Other academic)
    Abstract [en]

    The ASSET-Road project is focussing on improving road safety and road traffic by pushing different transportation stakeholders to interact between each other and integrating modern communication and sensing technologies. This deliverable is the result of the project tasks 3.1 (Regulation knowledge & awareness study), 3.2 (Situation identification & information presentation) and part of task 3.3 (Smart information provision Mechanism & HMI). In brief, objectives of the deliverable are: 1. to report the study conducted in task 3.1 where information about how deep drivers’ knowledge is (for truck and coaches drivers) have been collected in several countries in relation to road and safety regulations (e.g. speed limits on different roads, traffic rules, safety equipments, etc.). This is the first part of the document and includes two studies, the first one conducted in Europe and the second one conducted in Tanzania; a comparison between them is proposed; 2. to describe the smart In-Vehicle Information System specifications based on the requirements collected in WP1 (task 1.2 Users needs and requirements). In this section systems features are briefly introduced and the simulator study setup where the system will be tested is described, including scenario setup, situation identification and simulator iterations.

  • 16.
    Carsten, Oliver
    et al.
    University of Leeds.
    Kircher, Katja
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Jamson, Samantha
    University of Leeds.
    Vehicle-based studies of driving in the real world: The hard truth?2013In: Accident Analysis and Prevention, ISSN 0001-4575, E-ISSN 1879-2057, Vol. 58, p. 162-174Article in journal (Refereed)
    Abstract [en]

    Real-world studies of driving behaviour and safety have face validity and have the distinct advantage of focussing on driving in its natural habitat. But their very naturalism can lead to problems with confounds and with noise in the data. This paper reviews the three major categories of on-road studies — controlled observation, field operational tests and naturalistic driving studies — and discusses the major applications of each study type. It also assesses some of the methodological issues that arise in one or more category of study.

  • 17.
    Dukic, Tania
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Ahlström, Christer
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Patten, Christopher
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Kettwich, Carmen
    Karlsruhe Institute of Technology.
    Kircher, Katja
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Effects of electronic billboards on driver distraction.2013In: Traffic Injury Prevention, ISSN 1538-9588, E-ISSN 1538-957X, Vol. 14, no 5, p. 469-76Article in journal (Refereed)
    Abstract [en]

    OBJECTIVE: There is an increase in electronic advertising billboards along major roads, which may cause driver distraction due to the highly conspicuous design of the electronic billboards. Yet limited research on the impact of electronic billboards on driving performance and driver behavior is available. The Swedish Transport Administration recently approved the installation of 12 electronic billboards for a trial period along a 3-lane motorway with heavy traffic running through central Stockholm, Sweden. The aim of this study was to evaluate the effect of these electronic billboards on visual behavior and driving performance.

    METHOD: A total of 41 drivers were recruited to drive an instrumented vehicle passing 4 of the electronic billboards during day and night conditions. A driver was considered visually distracted when looking at a billboard continuously for more than 2 s or if the driver looked away from the road for a high percentage of time. Dependent variables were eye-tracking measures and driving performance measures.

    RESULTS: The visual behavior data showed that drivers had a significantly longer dwell time, a greater number of fixations, and longer maximum fixation duration when driving past an electronic billboard compared to other signs on the same road stretches. No differences were found for the factors day/night, and no effect was found for the driving behavior data.

    CONCLUSION: Electronic billboards have an effect on gaze behavior by attracting more and longer glances than regular traffic signs. Whether the electronic billboards attract too much attention and constitute a traffic safety hazard cannot be answered conclusively based on the present data.

  • 18.
    Eriksson, Alexander
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Lindström, Anders
    Veridict AB.
    Seward, Albert
    Veridict AB.
    Seward, Alexander
    Veridict AB.
    Kircher, Katja
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Can user-paced, menu-free spoken language interfaces improve dual task handling while driving?2014In: Human-Computer Interaction. Advanced Interaction Modalities and Techniques: 16th International Conference, HCI International 2014, Heraklion, Crete, Greece, June 22-27, 2014, Proceedings, Part II / [ed] Masaaki Kurosu, Springer, 2014, p. 394-405Conference paper (Refereed)
    Abstract [en]

    The use of speech-based interaction over traditional means of interaction in secondary tasks may increase safety in demanding environments with high requirements on operator attention. Speech interfaces have suffered from issues similar to those of visual displays, as they often rely on a complex menu structure that corresponds to that of visual systems. Recent advances in speech technology allow the use of natural language, eliminating the need for menu structures and offering a tighter coupling between the intention to act and the completion of the action. Modern speech technology may not only make already existing types of interaction safer, but also opens up for new applications, which may enhance safety. One such application is a speech-based hazard reporting system. A small fixed-base simulator study showed that drivers adapt the timing of the hazard reports to the situation at hand, such that an increase in reported workload was avoided.

  • 19.
    Eriksson, Alexander
    et al.
    University of Southampton.
    Solis Marcos, Ignacio
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Kircher, Katja
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Västfjäll, Daniel
    Linköping Universitet.
    Stanton, Neville A.
    University of Southampton.
    The Development of a Method to Assess the Effects of Traffic Situation and Time Pressure on Driver Information Preferences2015In: Engineering Psychology and Cognitive Ergonomics: 12th International Conference, EPCE 2015, Held as Part of HCI International 2015, Los Angeles, CA, USA, August 2-7, 2015, Proceedings / [ed] Don Harris, Springer, 2015, p. 3-12Conference paper (Refereed)
    Abstract [en]

    Contemporary Driving Automation (DA) is quickly approaching a level where partial autonomy will be available, relying on transferring control back to the driver when the operational limits of DA is reached. To explore what type of information drivers might prefer in control transitions an online test was constructed. The participants are faced with a set of still pictures of traffic situations of varying complexity levels and with different time constraints assituations and time available is likely to vary in real world scenarios. The choices drivers made were then assessed with regards to the contextual and temporal information available to participants. The results indicate that information preferences are dependent both on the complexity of the situation presented as well as the temporal constraints. The results also show that the different temporal and contextual conditions had an effect on decision-making time, where participants orient themselves quicker in the low complexity situations or when the available time is restricted. Furthermore, the method seem to identify changes in behaviour caused by varying the traffic situation and external time pressure. If the results can be validated against a more realistic setting, this particular method may prove to be a cost effective, easily disseminated tool which has potential to gather valuable insights about what information drivers prioritize when confronted with different situations.

  • 20.
    Falkmer, Torbjörn
    et al.
    Swedish National Road and Transport Research Institute.
    Vogel, Katja
    Swedish National Road and Transport Research Institute.
    Gregersen, Nils Petter
    Swedish National Road and Transport Research Institute.
    The Test of Visual Perceptual Skills (non-motor) Upper Level is Not a Valid Predictor for the Outcome of Driver Education2001In: Scandinavian Journal of Occupational Therapy, ISSN 1103-8128, E-ISSN 1651-2014, Vol. 8, no 2, p. 72-78Article in journal (Refereed)
    Abstract [en]

    In order to reduce the monetary and personal costs of driver training for persons with cerebral palsy, it is of interest to find a predictor that is able to select potential license holders. Previous research has shown that such a predictor could be one that assesses visual perception. In the present study, the Test of Visual Perceptual Skills (non-motor) Upper Level, was validated for predicting the outcome of driver education. It was found that using the test for this purpose could not be recommended. The findings of the present study were not in accordance with the results of other studies on the predictive value of perceptual tests regarding the ability to drive, owing to the use of different methods. Future studies should focus on cross-validation of perceptual tests for different types of independent variables, such as driving license or not, accident involvement and driving ability.

  • 21.
    Fors, Carina
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Ahlström, Christer
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Sörner, Per
    Smart eye.
    Kovaceva, Jordanka
    Volvo cars.
    Hasselberg, Emanuel
    Smart eye.
    Krantz, Martin
    Smart eye.
    Grönvall, John-Fredrik
    Volvo cars.
    Kircher, Katja
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Anund, Anna
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Camera-based sleepiness detection: final report of the project SleepEYE2011Report (Other academic)
    Abstract [en]

    Two literature reviews were conducted in order to identify indicators of driver sleepiness and distraction. Three sleepiness indicators – blink duration, blink frequency and Perclos – were implemented in the camera system.

    The aims of the study were firstly to develop and evaluate a low cost 1-camera unit for detection of driver impairment, and secondly to identify indicators of driver sleepiness and to create a sleepiness classifier for driving simulators.

    The project included two experiments. The first was a field test where 18 participants conducted one alert and one sleepy driving session on a motorway. 16 of the 18 participants also participated in the second experiment which was a simulator study similar to the field test.

    The field test data was used for evaluation of the 1-camera system, with respect to the sleepiness indicators. Blink parameters from the 1-camera system was compared to blink parameters obtained from a reference 3-camera system and from the EOG. It was found that the 1-camera system missed many blinks and that the blink duration was not in agreement with the blink duration obtained from the EOG and from the reference 3-camera system. However, the results also indicated that it should be possible to improve the blink detection algorithm since the raw data looked well in many cases where the algorithm failed to identify blinks.

    The sleepiness classifier was created using data from the simulator experiment. In the first step, the indicators identified in the literature review were implemented and evaluated. The indicators also included driving and context related parameters in addition to the blink related ones. The most promising indicators were then used as inputs to the classifier.

  • 22.
    Fors, Carina
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Kircher, Katja
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Ahlström, Christer
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Interface design of eco-driving support systems: Truck drivers’ preferences and behavioural compliance2015In: Transportation Research Part C: Emerging Technologies, ISSN 0968-090X, E-ISSN 1879-2359, Vol. 58, p. 706-720Article in journal (Refereed)
    Abstract [en]

    The aim of the study was to investigate the perceived usefulness of various types of in-vehicle feedback and advice on fuel efficient driving. Twenty-four professional truck drivers participated in a driving simulator study. Two eco-driving support systems were included in the experiment: one that provided continuous information and one that provided intermittent information. After the simulator session, the participants were interviewed about their experiences of the various constituents of the systems. In general, the participants had a positive attitude towards eco-driving support systems and behavioural data indicated that they tended to comply with the advice given. However, different drivers had very different preferences with respect to what type of information they found useful. The majority of the participants preferred simple and clear information. The eco-driving constituents that were rated as most useful were advice on gas pedal pressure, speed guidance, feedback on manoeuvres, fuel consumption information and simple statistics. It is concluded that customisable user interfaces are recommended for eco-driving support systems for trucks.

  • 23.
    Gustafsson, Susanne
    et al.
    Swedish National Road and Transport Research Institute.
    Anund, Anna
    Swedish National Road and Transport Research Institute.
    Sörensen, Gunilla
    Swedish National Road and Transport Research Institute.
    Vogel, Katja
    Swedish National Road and Transport Research Institute.
    Samband mellan socioekonomisk bakgrund och användning av skyddsanordningar för barns säkerhet i bil: en litteraturstudie med resultat från Sverige, Tyskland, USA och Australien2003Report (Other academic)
    Abstract [sv]

    En genomgång av litteratur från Sverige, Tyskland, USA och Australien under

    1990- och 2000-talet rörande barn i bil har utförts. Undersökningens syfte

    var att samla kunskap om skillnader i användning och felanvändning av

    skyddsanordningar för barns säkerhet i bil beroende på sociala, ekonomiska,

    geografiska eller kulturella förhållanden. Vi studerade också om det hade

    genomförts några kampanjer eller andra insatser för att nå ut med information

    till olika grupper i samhället. I föreliggande studie beskrivs resultat från

    olika undersökningar av ickeanvändning samt felanvändning av

    skyddsutrustning. Ickeanvändning av skyddsutrustning, det vill säga att

    bälten inte används samt felanvändning av särskild skyddsutrustning för de

    barn som använder/borde använda det, förekommer i alla länderna.

    Ickeanvändningen av bälte ökar ofta med stigande ålder, liksom

    ickeanvändningen av särskild skyddsutrustning. Det finns en skillnad mellan

    länderna beträffande vilka barn, beroende på ålder och ibland vikt och/eller

    längd, som omfattas av lagar om bälten och särskilda skyddsutrustningar,

    vilket gör det svårt att jämföra de olika länderna. Felanvändning av

    skyddsutrustning är ytterligare ett problem. Det kan innebära både att barnet

    sitter i fel skydd för sin ålder eller vikt eller att utrustningen använts på

    fel sätt, till exempel att bältet inte är tillräckligt sträckt. I den lästa

    litteraturen visas på skillnader i användning och felanvändning av

    skyddsutrustning beroende på socioekonomisk bakgrund. Ickeanvändning och

    felanvändning är vanligare bland de barn vars föräldrar har en låg utbildning

    jämfört med barn till föräldrar med hög utbildning. Likaså är

    ickeanvändningen och felanvändningen av barnens skyddsutrustning lägre i

    hushåll med en högre inkomst jämfört med hushåll med lägre inkomst. Detta

    stöds ytterligare av det faktum att föräldrar som inte använder

    skyddsutrustning till sina barn lägger större vikt på kostnaden för att

    använda skyddsutrustningar till sina barn än föräldrar vars barn är skyddade.

    Barn som reser på landsväg är skyddade i större utsträckning än de som färdas

    i tätort. I flera undersökningar finns resultat som tyder på en större

    ickeanvändning och större felanvändning i folkgrupper med utländsk bakgrund

    eller där språket är ett annat än landets officiella språk. I en amerikansk

    studie omfattande alla delstater framkommer att det finns skillnader mellan

    delstaterna i användning av skyddsanordning för barn 5-14 år. Dessa

    skillnader antas bero på hur lagarna är utformade i de olika delstaterna.

  • 24.
    Ihs, Anita
    et al.
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Andersson, Jan
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Kircher, Katja
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Bolling, Anne
    Swedish National Road and Transport Research Institute, Traffic and road users, Vehicle technology and simulation.
    Trafikanternas krav på vägars tillstånd: en körsimulatorstudie2010Report (Other academic)
    Abstract [sv]

    In order to get a view on the road surface condition the Swedish Road Administration (SRA) uses both objective measurement mehods, mainly measurements of rut depth and unevenness, and road users, opinions on the roads condition. Objective measurements show that road surface condition in general has not changed to any greater extent during the latest years. Road user surveys show, however, that the road users, and not least the professional drivers, have become less satisfied with the operation and maintenace of the roads. To try to understand the cause of this discrepancy it is of interest to closer analyse the road users assessment of road surface condition. The report presents a driving simulator study, which is divided into two experiments. In the first experiment the importance of different impressions, i.e. visual appearance, noise and vibrations, is tested on a road surface with ruts as well as on a road surface with patchings/repairs. The analysis was based on driving data and on the drivers´ opinions on how comfortable and safe, respectively, the road was to drive on. The conclusion from the first experiment was that the visual apppearence alone does not influence speed, but lateral position. Noise has an influence on the variance of speed, and vibration has an influence on the variance of lateral position. Noise and vibration have an influence on speed in interaction with the visual appearance. The results of the drivers´ assessments of comfort and safety show a clear pattern where the visual appearance, the sound and the vibrations separately and in an additional way have an influence on the subjective experience of comfort and safety. In the second experiment eight road surfaces with different road surface conditions (patches, ruts, ruts filled with water, rough texture, unnevenness (two levels), cracks and edge deformations). The eight road surfaces grouped together in three different groups concerning the assessment of comfort and of safety, though not in the exact same way.

  • 25.
    Jamson, Samantha
    et al.
    University of Leeds.
    Kircher, Katja
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Brouwer, Rino
    TNO Human Factors.
    Methodological challenges and solutions in the EuroFOT project2009In: 16th World Congress and Exhibitionon Intelligent Transport Systems 2009: 16th ITS World Congress Stockholm, Sweden 21-25 September 2009 Volume 3 of 8, Stockholm, 2009, Vol. 3, p. 1768-1774Conference paper (Refereed)
    Abstract [en]

    The euroFOT project is undertaking Field Operational Tests to investigate the effects of eight safety functions. More than 1500 drivers of cars and trucks will participate with the focus being not only on the use of the systems under daily traffic conditions but also their impact on traffic safety, efficiency and environment.

    In order to do this, a methodology had to be developed that balanced rigorous experimental methods with the practicalities of running a field trial. This paper describes how the methodology for undertaking comparative analysis between the functions was developed, drawing on the FESTA guidelines.

  • 26.
    Kircher, Albert
    et al.
    Swedish National Road and Transport Research Institute.
    Vogel, Katja
    Swedish National Road and Transport Research Institute.
    Törnros, Jan
    Swedish National Road and Transport Research Institute.
    Bolling, Anne
    Swedish National Road and Transport Research Institute.
    Nilsson, Lena
    Swedish National Road and Transport Research Institute.
    Patten, Christopher
    Swedish National Road and Transport Research Institute.
    Malmström, Therese
    Ceci, Ruggero
    Mobile telephone simulator study2004Report (Other academic)
    Abstract [sv]

    The study consists of four separate experiments conducted in the VTI driving

    simulator. The common theme was to investigate how driver behaviour and

    traffic safety are influenced when the driver attends to another technical

    device while driving. The experiments were concerned with handsfree or

    handheld mobile phone conversation and dialling, receiving mobile phone SMS

    messages and watching a DVD film (the latter two being minor pilot

    experiments). In three of the experiments (mobile phone conversation, SMS,

    DVD) the participants drove a route which led through urban and rural

    environments, ranging from 90 km/h rural to 50 km/h urban environments. The

    urban environments differed in complexity (three levels). The driving

    distance was about 70 km. The dialling experiment used a rural environment

    with a speed limit of 110 km/h. The driving distance was about 15 km. In the

    main experiment dealing with mobile phone conversation, a number of driving

    performance measures were analysed: driving speed, variation in lateral

    position, deceleration, brake reaction time, headway, time to collision, etc.

    PDT (Peripheral Detection Task) was used as a measure of mental workload.

    Mobile phone conversation was found demanding in terms of mental workload. It

    also had effects on driving. Most effects were quite similar for the two

    phone modes (handsfree, handheld). Impaired reaction time performance was

    demonstrated in one of the situations for handheld mode. However, effects

    were found which could be interpreted as attempts to compensate for the

    increased workload caused by the mobile phone conversation: speed was reduced

    (more so for handheld than for handsfree mode), and time and distance headway

    increased. In spite of these compensatory behaviours, mental workload was

    still markedly increased by phone use. In the SMS experiment the participants

    braked later in one situation when reading the SMS message. No other effects

    were found in this minor experiment. In the DVD experiment, mental workload

    increased when watching the film, although this was compensated for to some

    extent by the increased distance headway to a lead vehicle. No compensation

    in terms of reduced driving speed, however, was apparent in this experiment.

    In the dialling experiment negative effects on traffic safety were evident

    from the larger variance of lateral car position during the dialling task for

    the handsfree phone mode. The mental workload also increased with the

    dialling task. Compensation in terms of reduced driving speed was apparent

    for both phone modes. Other aspects of mobile phone use while driving still

    remain to be analysed in more detail, such as starting or finishing a call,

    looking for a phone number to dial, mishaps like dropping the phone, etc.

  • 27.
    Kircher, Katja
    Swedish National Road and Transport Research Institute.
    Driver distraction: a review of the literature2007Report (Other academic)
    Abstract [en]

    Driver distraction has been defined in many different ways. The most important difference is whether only visual inattention or also cognitive inattention should be included. Many different methods have been used to assess the prevalence and types of driver distraction that occur, and to describe the consequences in terms of driving performance and crash involvement. There is strong agreement that distraction is detrimental for driving, and that the risk for crashes increases. Drivers rather opt for repeated glances instead of extending one single glance, if the secondary task demands attention for a longer period of time. However, repeated glances have more detrimental effects on driving performance than a single glance of the same duration as one of the repeated glances. Only recently the method of remote eye tracking has emerged, which enables real time identification of visual distraction. So far this method has mostly been used in driving simulators. Different algorithms that diagnose distracted drivers have been tested with promising results. In simulators it is difficult, however, to induce true distraction, due to the short duration of the experiment and the artificial setting. A prolonged field study under naturalistic conditions could provide new insights and validation of simulator studies.

  • 28.
    Kircher, Katja
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Low friction warnings: An assessment of three different approaches2007In: 14th World Congress on Intelligent Transport Systems, ITS 2007, 2007, Vol. 6, p. 4262-4273Conference paper (Refereed)
    Abstract [en]

    A driving simulator study was conducted with the goal to find the human machine interface with the highest potential to increase traffic safety. Different aspects of how driving behaviour was influenced were investigated. Low friction warnings were given several seconds in advance of the occurrence of low friction conditions. A display that advised drivers about a recommended maximum speed on low friction conditions led to higher speed reductions than a display of the stopping distance or a low friction warning symbol. Generally women displayed more careful behaviour than men did (less speeding, less curve cutting, longer overall travel time).

  • 29.
    Kircher, Katja
    Swedish National Road and Transport Research Institute.
    Simulator Study2007Report (Other academic)
    Abstract [en]

    The main aim of the simulator study in INTRO WP 2.3 was to investigate how a low friction warning system in vehicles would influence traffic safety, and to identify the interface with the highest potential to increase traffic safety in low friction conditions. The stopping distance model which was determined in other tasks within WP 2 was used as a base for the low friction warnings in the present task.

  • 30.
    Kircher, Katja
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Ahlström, Christer
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Can we trust driver behaviour assessment?: Examples from research in simulators and in the field2012In: Proceedings of Measuring Behavior 2012 (Utrecht, The Netherlands, August 28-31, 2012) / [ed] A.J. Spink, F. Grieco, O.E. Krips, L.W.S. Loijens, L.P.J.J. Noldus, and P.H. Zimmerman, Utrecht, NL, 2012, p. 55-58Conference paper (Refereed)
    Abstract [en]

    It is very common to compare mean values of driving performance indicators (PI) like mean speed, the standard deviation of lateral position, time headway, mean glance duration, and many more, in order to investigate possible differences between different treatment groups. Just like all the PIs mentioned here, most of them describe aspects of the control level of driving behaviour according to Michon’s control hierarchy. When means differ significantly between treatment groups, this is often interpreted in relation to traffic safety gains or losses.

    In this paper we are going to discuss possible pitfalls with the use and interpretation of such performance indicators, based on examples from studies carried out in driving simulator and in the field. Finally, we suggest a number of possible solutions to avoid some of the issues discussed here.

  • 31.
    Kircher, Katja
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Trafikanttillstånd, TIL.
    Ahlström, Christer
    Swedish National Road and Transport Research Institute, Traffic and road users, Trafikanttillstånd, TIL.
    Evaluation of methods for the assessment of attention while driving2017In: Accident Analysis and Prevention, ISSN 0001-4575, E-ISSN 1879-2057Article in journal (Refereed)
    Abstract [en]

    The ability to assess the current attentional state of the driver is important for many aspects of driving, not least in the field of partial automation for transfer of control between vehicle and driver. Knowledge about the driver's attentional state is also necessary for the assessment of the effects of additional tasks on attention. The objective of this paper is to evaluate different methods that can be used to assess attention, first theoretically, and then empirically in a controlled field study and in the laboratory.

    Six driving instructors participated in all experimental conditions of the study, delivering within-subjects data for all tested methods. Additional participants were recruited for some of the conditions. The test route consisted of 14. km of motorway with low to moderate traffic, which was driven three times per participant per condition. The on-road conditions were: baseline, driving with eye tracking and self-paced visual occlusion, and driving while thinking aloud. The laboratory conditions were: Describing how attention should be distributed on a motorway, and thinking aloud while watching a video from the baseline drive.

    The results show that visual occlusion, especially in combination with eye tracking, was appropriate for assessing spare capacity. The think aloud protocol was appropriate to gain insight about the driver's actual mental representation of the situation at hand. Expert judgement in the laboratory was not reliable for the assessment of drivers' attentional distribution in traffic. Across all assessment techniques, it is evident that meaningful assessment of attention in a dynamic traffic situation can only be achieved when the infrastructure layout, surrounding road users, and intended manoeuvres are taken into account. This requires advanced instrumentation of the vehicle, and subsequent data reduction, analysis and interpretation are demanding. In conclusion, driver attention assessment in real traffic is a complex task, but a combination of visual occlusion, eye tracking and thinking aloud is a promising combination of methods to come further on the way. .

  • 32.
    Kircher, Katja
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Trafikanttillstånd, TIL.
    Ahlström, Christer
    Swedish National Road and Transport Research Institute, Traffic and road users, Trafikanttillstånd, TIL.
    Evaluation of methods for the assessment of attention while driving2016Conference paper (Refereed)
    Abstract [en]

    The ability to assess the current attentional state of the driver is important for many aspects of driving, not least in the field of automation. Knowledge about the driver’s attentional state is necessary for the assessment of the effects of additional tasks on attention, and for the transfer of control between vehicle and driver. Therefore, different methods that can be used to assess attention, were evaluated theoretically and then empirically in a controlled field study and in the laboratory.

    Six driving instructors participated in all experimental conditions of the study, delivering within-subjects data for all tested methods. Additional participants were recruited for some of the conditions. The test route consisted of 14 km of motorway with low to moderate traffic, which was driven three times per participant per condition. The on-road conditions were: baseline, driving with eye tracking and self-paced visual occlusion, and driving while thinking aloud. The laboratory conditions were: Describing how attention should be distributed on a motorway, giving a written percentage distribution for a motorway situation, and thinking aloud while watching a video from the baseline drive. For the analysis the on-road data were split into manoeuvres. Attention was distributed differently depending on manoeuvre type, which was evident from both eye tracking, occlusion, the think aloud protocol and the lab-based methods, therefore it is recommended to consider the type of manoeuvre when making attention assessments. The visual occlusion method is a valuable tool to assess spare visual capacity. Especially in combination with eye tracking, and in comparison with “baseline” driving it shows which glances are experienced as containing necessary information, and which glances are “spare” glances. The think aloud method is a meaningful tool to approach the driver’s actual mental representation of the situation at hand. However, this method should be used with caution, as talking about one’s attentional distribution in fact changes one’s glance behaviour in comparison to baseline driving. Expert judgements in the laboratory did not turn out to be a reliable and useful method for the assessment of drivers’ attentional distribution in traffic. This may be due to difficulties in verbally accessing procedural knowledge.

    For successful attention assessment in a dynamic traffic situation it is important to have access to information about the manoeuvres made by the driver in relation to other vehicles on the road. Also, knowledge about the road layout, speed limit etc. should be incorporated into the assessment. All this requires a rather advanced instrumentation of the experimental vehicle. In addition, data reduction, analysis and interpretation are demanding. To summarise, driver attention assessment in real traffic is a complex task, but a triangulation of visual occlusion, eye tracking and thinking aloud is a promising combination of methods to come further on the way.

  • 33.
    Kircher, Katja
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Ahlström, Christer
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Evaluation of methods for the assessment of minimum required attention2015Report (Other academic)
    Abstract [en]

    The empirical methods eye tracking while driving, visual occlusion while driving, think aloud while driving, expert judgement in the laboratory and think aloud while watching video are evaluated for their usefulness to assess driver attention in real traffic. Using a within-subjects design, six driving instructors drove three 14-kilometre-laps on a motorway per driving condition. Additional participants took part in sub-sets of the conditions. The methods were evaluated both with respect to practical implications and to the results that could be obtained with them. Glance behaviour and self-paced visual occlusion varied between different manoeuvre types (lane change – two directions, driving in left or right lane) and also between drivers. For the assessment of the attentional requirements of different traffic situations it is recommended to identify “situational prototypes” and related manoeuvres. The attention assessment should then be made with eye tracking in combination with visual occlusion, complemented with the think aloud technique. It is important to consider inter-individual variations in the process of identifying general attentional requirements for a prototypical situation/manoeuvre combination. Information about surrounding traffic needs to be obtained for a correct assessment. Preliminary results indicate that it is important to adopt a manoeuvre-oriented view, for example when identifying visual targets, instead of using a static gaze target classification scheme.

  • 34.
    Kircher, Katja
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Ahlström, Christer
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Issues related to the driver distraction detection algorithm AttenD2009Conference paper (Refereed)
    Abstract [en]

    Driver distraction is a contributing factor to many crashes and a real-time distraction warning system has the potential to mitigate or circumvent many of these crashes. The objective of this paper is to thoroughly describe the distraction detection algorithm AttenD and explain the theory underlying different design choices. Future aspects and distraction warning strategies will be discussed as well.

    In summary, AttenD is an eye-tracker based distraction detection algorithm which identifies visual distraction in real-time based on single long glances as well as repetitive glances. The core idea of the algorithm is a 2-second time buffer which is decremented when the driver looks away from the road and incremented when the driver looks back at the road. If the buffer runs empty, the driver’s state is classified as distracted.

  • 35.
    Kircher, Katja
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Trafikanttillstånd, TIL.
    Ahlström, Christer
    Swedish National Road and Transport Research Institute, Traffic and road users, Trafikanttillstånd, TIL.
    Minimum Required Attention: A Human-Centered Approach to Driver Inattention2017In: Human Factors, ISSN 0018-7208, E-ISSN 1547-8181, Vol. 59, no 3, p. 471-484Article in journal (Refereed)
    Abstract [en]

    Objective: To propose a driver attention theory based on the notion of driving as a satisficing and partially self-paced task and, within this framework, present a definition for driver inattention.

    Background: Many definitions of driver inattention and distraction have been proposed, but they are difficult to operationalize, and they are either unreasonably strict and inflexible or suffer from hindsight bias.

    Method: Existing definitions of driver distraction are reviewed and their shortcomings identified. We then present the minimum required attention (MiRA) theory to overcome these shortcomings. Suggestions on how to operationalize MiRA are also presented.

    Results: MiRA describes which role the attention of the driver plays in the shared "situation awareness of the traffic system." A driver is considered attentive when sampling sufficient information to meet the demands of the system, namely, that he or she fulfills the preconditions to be able to form and maintain a good enough mental representation of the situation. A driver should only be considered inattentive when information sampling is not sufficient, regardless of whether the driver is concurrently executing an additional task or not.

    Conclusions: The MiRA theory builds on well-established driver attention theories. It goes beyond available driver distraction definitions by first defining what a driver needs to be attentive to, being free from hindsight bias, and allowing the driver to adapt to the current demands of the traffic situation through satisficing and self-pacing. MiRA has the potential to provide the stepping stone for unbiased and operationalizable inattention detection and classification.

  • 36.
    Kircher, Katja
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Ahlström, Christer
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Predicting visual distraction using driving performance data2010In: Annals of advances in automotive medicine, ISSN 1943-2461, Vol. 54, p. 333-342Article in journal (Refereed)
    Abstract [en]

    Behavioral variables are often used as performance indicators (PIs) of visual or internal distraction induced by secondary tasks. The objective of this study is to investigate whether visual distraction can be predicted by driving performance PIs in a naturalistic setting. Visual distraction is here defined by a gaze based real-time distraction detection algorithm called AttenD. Seven drivers used an instrumented vehicle for one month each in a small scale field operational test. For each of the visual distraction events detected by AttenD, seven PIs such as steering wheel reversal rate and throttle hold were calculated. Corresponding data were also calculated for time periods during which the drivers were classified as attentive.

    For each PI, means between distracted and attentive states were calculated using t-tests for different time-window sizes (2 - 40 s), and the window width with the smallest resulting p-value was selected as optimal. Based on the optimized PIs, logistic regression was used to predict whether the drivers were attentive or distracted. The logistic regression resulted in predictions which were 76 % correct (sensitivity = 77 % and specificity = 76 %).

    The conclusion is that there is a relationship between behavioral variables and visual distraction, but the relationship is not strong enough to accurately predict visual driver distraction. Instead, behavioral PIs are probably best suited as complementary to eye tracking based algorithms in order to make them more accurate and robust.

  • 37.
    Kircher, Katja
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Ahlström, Christer
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    The driver distraction detection algorithm AttenD2013In: Driver distraction and inattention: Advances in research and countermeasures / [ed] Michael A. Regan, John D. Lee, Trent W. Victor, Surrey, UK: Ashgate, 2013, p. 327-348Chapter in book (Refereed)
  • 38.
    Kircher, Katja
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Ahlström, Christer
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    The impact of tunnel design and lighting on the performance of attentive and visually distracted drivers2012In: Accident Analysis and Prevention, ISSN 0001-4575, E-ISSN 1879-2057, Vol. 47, p. 153-161Article in journal (Refereed)
    Abstract [en]

    The crash risk in tunnels is lower than on the open road network, but the consequences of a crash are often severe. Proper tunnel design is one measure to reduce the likelihood of crashes, and the objective of this work is to investigate how driving performance is influenced by design factors, and whether there is an interaction with secondary task load. Twenty-eight drivers participated in the simulator study. A full factorial within subject design was used to investigate the tunnel wall colour (dark or light-coloured walls), illumination (three different levels) and task load (with or without a visual secondary task). The results show that tunnel design and illumination have some influence on the drivers’ behaviour, but visual attention given to the driving task is the most crucial factor, giving rise to significant changes in both driving behaviour and visual behaviour. The results also indicate that light-coloured tunnel walls are more important than strong illumination to keep the drivers’ visual attention focused forward.

  • 39.
    Kircher, Katja
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Ahlström, Christer
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Fors, Carina
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Forward, Sonja
    Swedish National Road and Transport Research Institute, Society, environment and transport, Mobility, actors and planning processes.
    Gregersen, Nils Petter
    Swedish National Road and Transport Research Institute.
    Hjälmdahl, Magnus
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Jansson, Jonas
    Swedish National Road and Transport Research Institute, Traffic and road users.
    Lindberg, Gunnar
    Swedish National Road and Transport Research Institute, Society, environment and transport, Transport economics Stockholm.
    Nilsson, Lena
    Swedish National Road and Transport Research Institute, Traffic and road users.
    Patten, Christopher
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Countermeasures against dangerous use of communication devices while driving –: a toolbox2012Report (Other academic)
    Abstract [en]

    This report outlines possible means to reduce the dangerous usage of mobile phones and other communication devices while driving. An important aspect of this commission was to demonstrate alternatives to legislation. The suggested countermeasures cover several areas. One is technical solutions, including countermeasures directed towards the infrastructure, the vehicle and the communication device. Another area includes education and information and describes different ways to increase knowledge and understanding. Furthermore, there are different possibilities for how society can influence the behaviour of individuals, both via bans, recommendations and incentives. The usage of communication devices while driving has both advantages and disadvantages. How to deal with device usage is a complex problem, and it is unlikely that one single countermeasure can provide a complete solution. One countermeasure may even depend on the implementation of others. The exact effect of most countermeasures is hard to predict, and possible side effects may occur. It is therefore necessary to be pragmatic, meaning that countermeasures whose advantages outweigh their disadvantages should be implemented. Also, different countermeasures can reinforce each other which may attenuate negative side effects. It is our opinion that a combination of different countermeasures – which educate and inform the driver while at the same time support him or her in a safe usage of communication devices – is preferable to a law against communication device usage while driving. Continuous follow-ups are necessary to ensure the outcome of implemented countermeasures.

  • 40.
    Kircher, Katja
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Ahlström, Christer
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Gregersen, Nils Petter
    Swedish National Road and Transport Research Institute, Society, environment and transport, Mobility, actors and planning processes.
    Patten, Christopher
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Why Sweden should not do as everybody else does2013In: PROCEEDINGS of the 3rd International Conference on Driver Distraction and Inattention, September 4-6, 2013, Gothenburg, Sweden, Göteborg, Sweden, 2013Conference paper (Refereed)
    Abstract [en]

    Sweden is the only country in Europe that does not outlaw handheld phone use while driving. This puts some political pressure on Sweden. The Swedish Government commissioned VTI to conduct a literature review on the effects of mobile communication on driving performance, on the legal situation in other countries, and whether there were any documented effects of a legislation. The literature showed that mobile communication does influence driving behaviour, but there appears to be no increased crash risk in real traffic.

    Also, laws do not have a lasting effect on how much drivers use their telephones. Therefore, the Swedish Government commissioned VTI to suggest countermeasures against the dangerous use of communication devices. Several countermeasures were presented, ranging from technical solutions over monetary incentives to education and information. It was stressed that no single countermeasure was expected to be satisfactory in itself, and that it is paramount to work with a human centred perspective. While the government proposed in December 2012 not to outlaw handheld phone use, the united political opposition, via its majority in the parliament, mandated the government in March 2013 to pass such a law. Besides that, the government proposed amendments to the current regulations for quick action.

  • 41.
    Kircher, Katja
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Ahlström, Christer
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Kircher, Albert
    Swedish National Road and Transport Research Institute, Traffic and road users, Vehicle technology and simulation.
    Comparison of two eye-gaze based real-time driver distraction detection algorithms in a small-scale field operational test2009In: Proceedings of the 5th International Driving Symposium on Human Factors in Driver Assessment and Design, 2009, p. 16-23Conference paper (Refereed)
    Abstract [en]

    Driver distraction is a field which has received increasing attention in the last years, especially after it became evident that distraction is a major factor contributing to road casualties. Monitoring, detecting and limiting driver distraction could contribute significantly to improve road traffic safety. With the introduction of novel unobtrusive gaze-tracking systems real-time algorithms based on the driver’s gaze direction can be developed for driver distraction warning systems.

    The study describes and compares two different algorithms for gaze-based driver distraction detection based on the eye tracking data obtained in a field study. One algorithm relies on the metric “percent road centre” of gaze direction, the other on gaze zones in the vehicle. Results show that both algorithms have potential for detecting driver distraction, but that no effect of the distraction warnings on attention as defined by the algorithms could be observed.

  • 42.
    Kircher, Katja
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Ahlström, Christer
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Kircher, Albert
    Swedish National Road and Transport Research Institute, Traffic and road users, Vehicle technology and simulation.
    The relationship between glance direction and eye tracking quality based on data from a long-term field study2009In: ITS in Daily Life, Stockholm, 2009Conference paper (Refereed)
    Abstract [en]

    It has been shown that distraction is a major factor contributing to road casualties. Detecting and limiting driver impairment could improve road safety. With the introduction of unobtrusive gaze-tracking systems gaze based real-time algorithms can be developed for driver state monitoring.

    The data reported here stem from an extended field study, during which seven drivers used an instrumented car for one month each. Eye tracking quality is best when the gaze is directed to the road center. The head tracking data show a bimodal distribution, which is interpreted as the drivers’ leaning the head against the head rest at times.

  • 43.
    Kircher, Katja
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Human Factors in the Transport System.
    Ahlström, Christer
    Swedish National Road and Transport Research Institute, Traffic and road users, Human Factors in the Transport System.
    Nylin, Magnus
    Linköpings Universitet.
    Mengist, Alachew
    Linköpings Universitet.
    Tactical steering behaviour under irrevocable visual occlusion2018In: Transportation Research Part F: Traffic Psychology and Behaviour, ISSN 1369-8478, E-ISSN 1873-5517, Vol. 55, p. 67-77Article in journal (Refereed)
    Abstract [en]

    Objective: To investigate the extent of a driver's mental model with irrevocable visual occlusion and analysing the distance to crash. Background: Drivers have a mental model of the immediate surroundings which allows them to predict their own as well as others' travel paths. To navigate safely through traffic, this mental model has to be updated frequently to remain valid. In between information sampling events, the mental model will become outdated over time, as the traffic system is dynamic.

    Method: A simulator study with 22 participants was conducted to investigate the information decay in the mental model. This was implemented by extending visual occlusion until the driver collided with another vehicle or ran off the road, thus providing an estimate of how long it takes until the mental model becomes obsolete.

    Results: An analysis of variance with the factors curve direction, curve radius and traffic showed that curve radius did not influence the distance to crash. Without traffic, drivers veered off the road sooner in right curves. Adding traffic eliminated this difference. Traffic ahead led to a shortened distance to crash. Compared to a tangential travel path from the current lateral position at the time of the occlusion, drivers crashed on average 2.6 times later than they would have, had they not had any mental model of the situation.

    Conclusions: The drivers' mental representation of the future situation seems to include information on how to act, to alleviate deviations in yaw angle, including and considering the presence of other road users.

  • 44.
    Kircher, Katja
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Ahlström, Christer
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Palmqvist, Lisa
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Adell, Emeli
    Trivector Traffic.
    Bicyclists‘ speed adaptation strategies when conducting self-paced vs. system-paced smartphone tasks in traffic2015In: Transportation Research Part F: Traffic Psychology and Behaviour, ISSN 1369-8478, E-ISSN 1873-5517, Vol. 28, p. 55-64Article in journal (Refereed)
    Abstract [en]

    The increasing prevalence of mobile phone usage while cycling has raised concerns, even though the number of cyclists involved in accidents does not increase at a comparable rate. A reason for this may be how cyclists adapt travelling speed and task execution to the current traffic situation. The aim of this study is to investigate speed adaptation among cyclists when conducting self-paced (initiated by the cyclist) vs. system-paced (initiated by somebody else) smartphone tasks in real traffic. Twenty-two cyclists completed a track in real traffic while listening to music, receiving and making calls, receiving and sending text messages, and searching for information on the internet. The route and the types of tasks were controlled, but the cyclists could choose rather freely when and where along the route to carry out the tasks, thus providing semi-naturalistic data on compensatory behaviour. The results clearly show that cyclists use conscious strategies to adapt their speed to accommodate the execution of secondary phone tasks. Regarding tactical behaviour, it was found that cyclists kept on cycling in 80% of the system-paced cases and in 70% of the self-paced cases. In the remaining cases, the cyclists chose to execute the phone task while standing still or when walking. Compared to the baseline (17.6 ± 3.5 km/h), the mean speed was slightly increased when the cyclists listened to music (18.2 ± 3.7 km/h) and clearly decreased when they interacted with the phone (13.0 ± 5.0 km/h). The speed reduction profile differed between self-paced and system-paced tasks with a preparatory speed reduction before task initiation for self-paced tasks. In conclusion, when the cyclists had the chance they either stopped or adapted their speed proactively to accommodate the execution of the phone task. For self-paced tasks, the speed reduction was finalised before task initialisation, and for system-paced tasks the speed adaptation occurred in reaction to the incoming task. It is recommended to investigate whether the observed compensatory behaviour is enough to offset the possible negative effects of smartphone use.

  • 45.
    Kircher, Katja
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Ahlström, Christer
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Rydström, Annie
    Volvo Cars.
    Ljung Aust, Mikael
    Volvo Cars.
    Ricknäs, Daniel
    Scania.
    Almgren, Susanne
    Saab Automobile.
    Nåbo, Arne
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Secondary Task Workload Test Bench – 2TB: final report2014Report (Other academic)
    Abstract [en]

    The main aim of this study was to investigate a selection of commonly used performance indicators (PIs) that have been reported to be sensitive to distraction and workload. More specifically, the PIs were tested for their ability to differentiate between task modalities (visual, cognitive and haptic) and task difficulty (easy, medium and hard). It was investigated whether possible differences were constant across two traffic situations (with/without lead vehicle) and two driving simulators. The experiment was conducted in the VTI Driving Simulator III, an advanced moving-base simulator, and in the Volvo Car Corporation driving simulator, an advanced fixed-base simulator. Both simulators were equipped with Smart Eye Pro eye tracking systems. A visual, a cognitive and a haptic secondary task were chosen to test the ability of the PIs to distinguish between the tasks’ loading on different modalities. Some of the main results from the study were:

    • There were only minor differences between the two simulators for driving behaviour as described by longitudinal PIs. There was no overall offset, and the main difference was that the visual task led to stronger speed reductions in the moving-base simulator, which influenced both the mean speed and the speeding index.
    • Regarding lateral PIs, major differences between the two simulators were found, both as a general offset and for those factor combinations that include modality and task difficulty level.
    • With the visual or the haptic task active, the drivers positioned themselves further to the left and the variation in lateral position was higher in the fixed-base simulator.
    • The number of lane crossings did not differ considerably between the simulators, but the lane departure area was larger on average in the fixed-base simulator, again influenced by modality, with the largest lane departure areas for the visual task, and in the case of the fixed-base simulator for the haptic task as well.
    • Most of the eye movement related PIs had a general offset between the simulators. The drivers in the fixed-base simulator accumulated more time with their eyes off the road, especially during the visual and the cognitive tasks, while the drivers in the moving-base simulator cast longer single glances at the display.
  • 46.
    Kircher, Katja
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Ahlström, Christer
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Thorslund, Birgitta
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Palmqvist, Lisa
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Adell, Emeli
    Trivector.
    Nilsson, Annika
    Trivector.
    Börefelt, Alexander
    Trivector.
    Cyklisters kompensationsstrategier när de använder mobil IT i trafiken2014Report (Other academic)
    Abstract [sv]

    Det finns en oro att cyklister som använder mobil IT utgör en trafikfara, men trots den ökande användningen verkar inte olyckstalen stiga. Målet med denna studie är därför att undersöka om och i så fall hur cyklister anpassar sitt beteende när de använder mobil IT medan de cyklar. Tjugotvå unga cyklister fick cykla fem varv längs en gata på en cykelbana i verklig trafik. Under varje varv fick de utföra olika uppgifter: cykla som vanligt, lyssna på musik, bli uppringda och ringa, skriva och läsa sms, samt söka efter information på internet. Rutten och uppgifterna var förutbestämda, men cyklisterna fick till stor del själva välja var och när de utförde de olika uppgifterna. På så sätt kunde vi studera om cyklisterna använde någon strategi när de använde mobil IT samtidigt som de cyklade. Resultaten visar tydligt att cyklisterna i studien väljer strategier för att ta sig an de olika telefonuppgifterna och att de flesta cyklisterna är medvetna om vilka strategier de använder. De valda strategierna skiljer sig åt mellan cyklister och mellan olika situationer, men de har en gemensam nämnare – att motverka belastning från telefonuppgiften. Jämfört med att bara cykla normalt (17.6 ± 3.5 km/h) så ökar hastigheten något vid musiklyssnande (18.2 ± 3.7 km/h) medan hastigheten sänks markant när cyklisten hanterar telefonen (13.0 ± 5.0 km/h). För de uppgifter som cyklisten själv kan påverka (ringa upp, skriva sms, söka information på internet) så sänks hastigheten i god tid före användandet och för resterande uppgifter så sänks hastigheten när ringsignalen hörs. I 26 % av fallen valde cyklisterna att stanna eller att leda cykeln medan de utförde telefonuppgifterna. Även för blickbeteendet var det väldigt liten skillnad mellan att cykla som vanligt och att cykla med musik. Cyklisterna själva beskriver även fler strategier som inte framgår av mätningarna. Till exempel anger vissa att de lyssnar mer aktivt eller att de bara använder en hörlur, att de planerar sitt användande genom längre framförhållning eller genom att inte använda mobil IT i korsningar, eller genom att mana sig själva till att vara mer alerta. Kompensationsstrategin beror också på hur van cyklisten är att använda mobil IT.

  • 47.
    Kircher, Katja
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Andersson, Jan
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Road safety in Tanzania: a questionnaire study2010In: Road safety on four continents: Abu Dhabi, United Arab Emirates, 28-30 March 2010: Conference proceedings / [ed] Gustafson, Kent, 2010, p. 1093-1104Conference paper (Refereed)
    Abstract [en]

    Even though the traffic fatality risk (fatalities per 100 000 inhabitants) in Tanzania is quite low, the fatality rate (fatalities per 10 000 vehicles) is one of the highest in the world. With increasing vehicle density this means that the number of people dying in traffic will increase dramatically in the near future. Therefore it is important to implement measures to increase traffic safety as soon as possible, and in order to be able to do this in an efficient way, it is important to investigate where the main problems lie. Within the EU project ASSET-Road a questionnaire study on road safety was conducted with 250 truck drivers in Tanzania. The study was done to increase the knowledge about the situation of the Tanzanian truckers, who are the most frequent road users in the country. The drivers were interviewed in three different towns in southern Tanzania, and participation was voluntary. The questionnaire treated demographics, the state of the drivers’ vehicles, the frequency of breakdowns and the maintenance of the vehicles. Further questions were concerned with driver behaviour, crash involvement, crash risk and crash mitigation. The drivers who participated in the study were predominantly male, their average age was 36 years. Around 40 % of the trucks did not have any seat belts installed, with a larger share of older trucks lacking belts. Most of the drivers who had seat belts reported to use them, however. Almost 40 % of the drivers reported to have been involved in at least one crash, and 45 % of those drivers had experienced fatal crashes. This underlines that crashes counted per vehicle are very frequent, and the results are often severe, especially when heavy vehicles are involved. Truck drivers reported to drive 10.6 hours without break on average, with several drivers reporting that they had to drive 24 hours without rest. When asked what the three most common crash causes were, driver related causes were prominent. Drivers were said to be reckless, further causes named often were drunkenness, inattention and sleepiness. One of the most mentioned crash mitigation strategy was driver education, but also improvement of the roads and the vehicles. This indicates that countermeasures should be implemented in an integrated fashion, taking the aspects driver, vehicle, infrastructure, legislature and other road users into account.

  • 48.
    Kircher, Katja
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Andersson, Jan
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Truck drivers' opinion on road safety in Tanzania: A questionnaire study2012In: Traffic Injury Prevention, ISSN 1538-9588, E-ISSN 1538-957X, Vol. 14, no 1, p. 103-111Article in journal (Refereed)
    Abstract [en]

    Even though the traffic fatality risk (fatalities per 100 000 inhabitants) in Tanzania is quite low, the fatality rate (fatalities per 10 000 vehicles) is one of the highest in the world. Since vehicle density will increase it is important to implement measures to increase traffic safety.

    Within the EU project ASSET-Road a questionnaire study on road safety was conducted with 250 truck drivers in Tanzania. The drivers were interviewed in three different towns in southern Tanzania, and participation was voluntary. The questionnaire treated demographics, the state of the drivers' vehicles, the frequency of breakdowns and the maintenance of the vehicles. Further questions concerned driver behaviour, crash involvement, crash risk and crash mitigation.

    Truck drivers reported to drive 10.6 hours without break on average, with several drivers reporting that they had to drive 24 hours without rest. Around 40% of the trucks did not have any seat belts installed, with a larger share of older trucks lacking belts. Most of the drivers who had seat belts reported to use them, however. Almost 40% of the drivers reported to have been involved in at least one crash, and 45% of those drivers had experienced fatal crashes. This underlines that crashes counted per vehicle are very frequent, and the results are often severe, especially when heavy vehicles are involved.

    When asked what the three most common crash causes were, driver related causes were named frequently. Drivers were said to be reckless, further crash causes named often were drunkenness, inattention and sleepiness. One of the most mentioned crash mitigation strategies was driver education, but also improvement of the roads and the vehicles.

  • 49.
    Kircher, Katja (ed)
    Swedish National Road and Transport Research Institute.
    A comprehensive framework of performance indicators and their interaction2008Report (Other academic)
  • 50.
    Kircher, Katja
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Trafikanttillstånd, TIL.
    Eriksson, Olle
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Forsman, Åsa
    Swedish National Road and Transport Research Institute, Traffic and road users, Traffic safety, society and road-user.
    Vadeby, Anna
    Swedish National Road and Transport Research Institute, Traffic and road users, Traffic safety, society and road-user.
    Ahlström, Christer
    Swedish National Road and Transport Research Institute, Traffic and road users, Trafikanttillstånd, TIL.
    Design and analysis of semi-controlled studies2016In: Transportation Research Part F: Traffic Psychology and Behaviour, ISSN 1369-8478, E-ISSN 1873-5517Article in journal (Refereed)
    Abstract [en]

    Semi-controlled studies provide a hybrid approach in between controlled experiments and naturalistic driving studies. As in controlled experiments, the researcher can assign participants to groups, select the route and define the tasks, but the participants are given more freedom when it comes to if, when, where and how to perform the tasks. Increased flexibility makes it possible to investigate how drivers use tactical behaviour to accommodate task execution. The disadvantage is decreased control and more complicated analyses.

    The main objective of this paper is to discuss how to analyse data obtained in semi-controlled studies.The analysis of data from a semi-controlled study include three types of variables:

    • variables that describe the experimental design
    • variables that describe the tactical choices of the participants
    • operational variables such as speed, lateral position or glance behaviour

    To analyse the three types of variables a two-step procedure is suggested. First, the tactical indicators are analysed with regard to the experimental design. Second, the operational indicators are analysed and the tactical indicators are used to divide participants into sub-populations.

    The semi-controlled design does not need any new statistical procedures to be developed. It is more important that the analysis conditions on the initial properties and not on structures that happen to occur during the experiment, like where the participant chose to do a certain task.We recommend to use the semi-controlled study method when investigating questions involving adaptive and compensatory behaviour on the tactical level. It is especially useful if causal relationships are of interest, if the data collection should be accelerated in comparison to naturalistic studies, and if certain geographical locations definitely should be included.

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