Connected and automated vehicles potentially offer solutions to some key challenges for National Road Administrations (NRAs), such as reduction of accidents, increasing network capacity etc. As a result of this potential, both industry and certain national governments are undertaking trials that are mainly focused on technological challenges such as the ability of vehicles to drive safely in “random” situations etc. Far less attention has been paid to questions around the implications for NRAs. The overall aim of the STAPLE project is to provide a comprehensive review of technological and non-technological aspects of the most relevant connected and automated driving test sites in order to understand the impact of these sites on the NRAs’ core business and functions.

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

Background: Little is known about whether individuals with autism spectrum disorder (ASD) or attention deficit hyperactive disorder (ADHD) experience any specific facilitators or barriers to driving education.

Objective: To explore the facilitators or barriers to driving education experienced by individuals with ASD or ADHD who obtained a learner’s permit, from the perspective of the learner drivers and their driving instructors.

Methods: Data were collected from 33 participants with ASD or ADHD, and nine of their driving instructors.

Results: Participants with ASD required twice as many driving lessons and more on-road tests than those with ADHD. Participants with ADHD repeated the written tests more than those with ASD. Driving license theory was more challenging for individuals with ADHD, whilst individuals with ASD found translating theory into practice and adjusting to “unfamiliar” driving situations to be the greatest challenges. Conclusion: Obtaining a driving license was associated with stressful training experience

Sammanfattningsvis definierar vi i denna guide ’smarta gator’ kort sagt som mångfunktionella, levande, långsamma, ekologiska och flexibla gator. Det övergripande målet med denna guide är följaktligen ”Smarta gator för en hållbar stadsutveckling”.

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

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

Genom höjda hastigheter för godståg finns möjligheter till en högre prioritering av trafikslaget hos tågtrafikledningen, vilket i sig är en kapacitetsvinst och bör ge upphov till bättre flöden och högre kapacitet på det svenska järnvägsnätet (framför allt på stambanorna). Simulatorer är ett effektivt och säkert sätt att undersöka effekter av förändringar på både förarbeteende och kapacitet.

Syftet med det här projektet var att skapa kapacitetshöjande möjligheter och åtgärder genom att ta fram en loktågssimulator och undersöka möjliga användningsområden för denna. Målet med projektet var att få fram en loktågssimulator, bestående av ett lok och ett antal vagnar, som kan användas i studier för att öka kapaciteten genom till exempel optimerad hastighet, och därmed förändrade bromsprofiler, för loktåg. Projektet har levererat kunskap i form av nya testmetoder, en loktågssimulator samt mjukvaruplattform för ytterligare testverksamhet.

Projektet genomfördes i tre successiva etapper. I den första etappen genomfördes en förstudie med lokförare, operatörer och problemägare, som gav forskarna en förståelse för förarmiljön. Här samlades även in en del av det underlag som krävdes för utveckling av loktågsimulatorn. I den andra etappen utvecklades en simulator för loktåg (mjukvara och hårdvara). Etapp tre var en valideringsstudie tillsammans med lokförare.

Ett förarbord av modellen Traxx köptes in från en tysk tillverkare. Fordonsmodellen utvecklades från en enstaka enhet, Reginamodell (motorvagnståg), till en kombination av flera enheter. Loktåget i simulatorn består av ett eller flera draglok samt ett antal vagnar med en total längd på maximalt 750 meter. Som draglok används ett lok av modellen Traxx. För varje enhet, lok och vagn, krävs data över enheten: längd, vikt, last, broms-, rull- och luftmotstånd. För lok tillkommer dessutom information om ljud, drivning, broms (återmatande elbroms samt konventionell pneumatisk broms (P-broms)), hyttutrustning med mera. För närvarande finns bansträckningen mellan Falköping–Jönköping–Forserum färdigmodellerad och kommer användas för loktågskörning med ATC. Modellen är konfigurerbar utifrån ett lok (Traxx) och i nuläget fyra olika vagnar. Dessa kan kopplas samman i olika kombinationer.

Några användningsområden som diskuterades redan vid projektstart var dels de som naturligt kan kopplas till följder av längre och tyngre tåg, dels de idéer som uppkom som följd av den utrustning som köptes in. Vid Trafikverkets vintermöte genomfördes en workshop där ytterligare användningsområden diskuterades. Några av dessa handlar om utbildning,energieffektiv körning eller projektering. Utbildning och vissa typer av studier går att göra med den nu existerande loktågsmodellen, medan andra kräver antingen validering av parametrar eller viss vidareutveckling av modellen.

Projektet har levererat kunskap i form av nya testmetoder, denna forskningsrapport och en produkt i form av en loktågssimulator samt mjukvaruplattform för ytterligare testverksamhet. Projektet har även levererat en nationell resurs i form av simulatormjukvara. Mjukvaran har lagt grunden för en kostnadseffektiv testverksamhet inom loktågsdomänen. En loktågssimulering (simulering av loktåg) har tagits fram, vilken kommer att vara värdefull som ett demonstrationsverktyg samt för utbildning, träning och projektering.

I samarbete med Hövding har en studie genomförts för att belysa hur olika aspekter bidrar till händelser där cykelhjälmen löser ut. Hjälmen registrerar kontinuerligt accelerationer och när en hjälm löser ut registreras denna information hos företaget. Företaget skickar då ut en inbjudan till cyklisten om att besvara en webbenkät som även inkluderar en inbjudan att medverka i en intervju. Studien bygger på data från tre olika källor –webbenkät, intervjuer och data från hjälmen – i syfte att öka förståelsen för varför en cykelolycka inträffar. Totalt var det 196 deltagare som besvarade enkäten och 50 deltagare som intervjuades. Dessutom samlades hjälmdata in från 355 cyklister, varav 264 cyklister hade varit inblandade i minst en händelse där hjälmen löst ut.

Ett av huvudresultaten är att det är en helt vanlig dag, på en vanlig resa när en erfaren cyklist, med hög utbildning, väl medveten om trafikregler och om vad som sker runt omkring, cyklar till eller från jobbet – och ”plötsligt händer det” och inte förrän då inser cyklisten hur utsatt den är. Studien visar att en komplex bild växer fram från de tre datakällor som nyttjats för att förstå varför en olycka egentligen sker. Exempelvis ökar halka risken för en händelse där Hövdingen löser ut och är det dessutom mörkt ökar risken ytterligare. Hjälmdata kunde styrka resultaten från webbenkäten och intervjuerna men också visa på att hjälmen, på de resor som slutat med att den löste ut, haft en högre aktiveringsgrad (det har skakat mer) än på resor tidigare (då hjälmen inte har löst ut). Vidare har hjälmen på resor som gjorts efter att den löst ut, visat att cyklisten cyklar med en lägre aktiveringsgrad. Det innebär att cyklisten gjort någon form av anpassning så som att cykla försiktigare (men inte långsammare). Slutligen visar resultaten på skillnader mellan cyklister på konventionella cyklar jämfört med elcyklar vad gäller inblandning i händelser där hjälmen lösts ut.

Background: Changes in modal choice is argued to be one way to reduce the emission of greenhouse gases. Increasing modal choices in favour of more environmentally friendly travel modes requires a better understanding of how these choices are actually made. The first aim of this study is therefore to examine how modal choice is related to subjective experiences as perceived accessibility, perceived satisfaction , habit, both before , after an intervention promoting public transport. The second aim is to examine how modal choice is affected by the intervention. Finally, the third aim is to examine how subjective experiences as perceived accessibility, perceived satisfaction, and habit are affected by the intervention.

Method: The design used is a before-and after-study with free public travel passes as the intervention (30-or 14-days free travel pass). Altogether, 52 travelers - distributed on two intervention groups and one control group - participated in the study. The 30-days free travel pass group constitutes 18 participants, the 14-days free travel pass group constitutes 19 participants while the control group constitutes 15 participants. During the before -period the participants were asked to register their modal choice using a digitalized application downloaded on their smart phones (the TravelVu app), to complete a short app-based questionnaire, and a web-based questionnaire. During the after-period, they were once again asked to register their modal choice and to complete a web-based questionnaire. All data collected were analyzed by variance or correlation analyses using the change between before-and after period as the dependent variable.

Conclusion: The intervention did not affect the modal choice or the subjective experiences. Over time, the participants did however increase their use of public transport and their cognitive evaluation of their everyday travel overall, while they decreased their use of car and became less reflective and less interested in trying out new alternative travel modes. These changes might be attributed to their participation in the present study.

The number of bicycling fatalities was 19 450 between 2010 and 2018 in Europe. The number of bicyclists killed when intoxicated by alcohol is harder to establish given the lack of reliable data. In Sweden, drunk bicycling is socially acceptable and legal (unless reckless). This experiment aimed to investigate how alcohol intoxication affect bicycling stability performance, executive functions, and self-rated ability. The experiment was completed on a wide treadmill that allowed control of several influencing factors such as speed and physical effort. Intoxicated and sober participants bicycled on the treadmill for five 10 minute sessions. Alcohol as administered incrementally to reach a target breath alcohol concentration level of 0.8‰. Stability decreased with intoxication; especially roll rate measurements were identified as being adequate indicators of bicycling instability. Executive function was negatively affected, and ability ratings decreased due to intoxication. The intoxicated participants were aware of their reduced ability to bicycle in a safe manner on a group level but not on an individual level. However, this insight does not affect their intention to bicycle intoxicated.

Individuals who do not fulfill required visual field standards have their driving license withdrawn in Sweden. However, understanding of the ability to compensate for this loss is limited. This study aimed to determine if reaction time and cognitive performance are important for safe driving in visual field loss (VFL) individuals. Visually demanding reaction time tasks of different complexity, for example, can help one understand why some VFL individuals drive as safely as normally sighted individuals. Twenty VFL individuals and 83 normally sighted individuals participated in a driving simulator experiment and an additional test battery. The driving task categorized VFL participants into two subgroups: passed or failed. Three reaction time tasks, four cognitive tests, and two meta-cognitive scales were completed. The passed VFL subgroup was faster than the failed subgroup in the context-dependent reaction time task and slower in the context-independent reaction time task. The passed subgroup performed equally well, or less well, on the cognitive tasks compared to the failed subgroup. The VFL participants performed less well than the normally sighted individuals on most cognitive tasks. However, VFL participants did not reflect on their driving ability (in meta-cognitive scales) in the same way as normally sighted individuals. There appear to be VFL subgroups in terms of ability to drive safely. Reaction time is important, but context dependent. Cognitive context-independent tests appear unrelated to driving test outcome for VFL individuals. The problems with context-independent testing of perceptual, cognitive, and meta-cognitive abilities when predicting safe driving capabilities are discussed. © 2019, The Author(s).

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

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

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

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

Bicycling accidents are a major traffic safety problem and are deemed ‘an unacceptable human and social price for EU citizens’. One of the major causes for bicycling accidents is loss of balance. A related influencing factor is alcohol intoxication. It is a primary, long term, safety objective to develop safety systems for the cyclist. The present work aimed to understand how to measure cyclists’ instability via steering and leaning inputs, while considering that steering and leaning might vary depending on the cycling task being performed. Of 28 participants, 19 were given doses of alcohol up to 1.0‰ and 9 remained sober (control group). Breath alcohol concentration was measured. The participants repeated the cycling test track session five times (with each block lasting 35 minutes). The track session contained three different tasks: cycling slalom, straight, and slowly. Speed, yaw rate, and roll rate were assessed continuously. Yaw rate and roll rate were relatively sensitive for the different cycling tasks. The threshold level of the angular velocity measurements was related to the cycling task performed. Alcohol intoxication at 0.7‰ had a significant impact on performance. The rather simple measurements used can detect instability. Instability should be measured differently depending on the cycling task performed. The study represents a small step towards a safety system for cyclists. 

Background

In collaboration with a bicycle airbag helmet company, data were collected to help explain events where head protections are deployed. The head protection records activations continuously, and when a head protection is deployed, this information is sent to the company. The company invited affected cyclists to (i) participate in a web survey, and (ii) share their data with researchers. The first aim of the study was to investigate the proportions between different severities of crashes, i.e., how many crashes with serious injuries occur for every crash with minor injuries, while the second aim was to predict when bicycle crashes will occur.

Method

A total of 196 cyclists completed the web survey. Participants were 20–76 years old (mean age 46 years) and consisted of 125 women and 55 men. The cyclists were highly educated, and 73 percent had completed a university or college education. In addition, head protection data were collected from 355 other cyclists, of which 264 had their helmet deployed.

Results

One of the 182 (included events) cyclists ended up in hospital care. The data collected indicated the proportions of cyclists who needed hospital care (1 = severe injuries), cyclists with injuries (15), slight injures (85) and cyclists who could continue as before (81 = no injuries). The head protection data confirmed the web survey findings, but also demonstrated that the head protection, on journeys that ended with head protection deployment, had a higher degree of activations before the event) compared to journeys where it was not deployed. Furthermore, on trips made after deployment, the head protection had lower levels of activations, which can be understood as the cyclists adapting their behavior by, for example, riding more carefully (but not slower).

Conclusion

This study highlights the proportions of events leading to minor injuries versus hospitalization. Activation measures (head protection conditions) can predict when events will occur, and cyclists will adjust their behavior accordingly following events.

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

Bicycling accidents are a well-known problem for traffic safety globally. Alcohol intoxication is one possible factor, although the exact number of accidents due to intoxication is difficult to establish. Not all bicyclists act in the same way, particularly when under the influence of alcohol, i.e., bicycling performance might be related to a bicyclist's personal characteristics. This study aimed to investigate if the bicyclist's characteristics (bicycling experience, physical fitness, or sensation seeking scores) influence bicycling stability, cognitive performance, or self-rated bicycling ability ratings at different levels of alcohol intoxication. The experiment was completed on a wide treadmill, which allowed control of several influencing factors such as speed and physical effort. Intoxicated and sober participants bicycled on the treadmill five times for 10 minutes each time, and breath alcohol concentration (BrAC) levels were measured five times. Participants were given doses of alcohol up to a BrAC level of 0.8%. 

För trafiksäkerheten är cykelolyckor är ett känt globalt problem eftersom de inte minskar i önskvärd riktning. Alkoholpåverkan är en förklaring, även om det exakta antalet cykelolyckor som involverar alkohol är svårt att beräkna. I Sverige är det socialt accepterat att cykla berusad så länge man inte är vårdslös (ingen promillegräns). Alla cyklister agerar inte lika, speciellt under alkoholpåverkan och cyklisters prestation kan vara relaterade till olika karaktärsdrag som till exempel, cykel vana, fysiska förutsättningar eller personens riskbenägenhet. Studiens syfte var att ta reda på om dessa karaktärsdrag kan påverka cyklisternas stabilitet, kognitiva prestation och självuppskattad cykelförmåga vid olika nivåer av alkoholpåverkan.  

Experimentet genomfördes på ett brett rullband (3,5 meter). Både alkoholpåverkade och nyktra personer cyklade på rullbandet totalt fem gånger á 10 minuter där berusningsnivåerna mättes med alkoholmätare efter varje cyklingsomgång. Dessutom genomförde deltagarna ett kognitivt test och besvarade frågor efter varje cykelomgång. Deltagarna fick alkoholdoser upp till 0.8 promille (den nyktra kontrollgruppen fick alkoholfri dryck). 

Resultaten visade att alkoholpåverkan hade en signifikant påverkan på cyklisternas stabilitet, på deras kognitiva prestation och på den självuppskattade cykelförmågan (en del inser att de blir sämre men inte alla). Resultaten visade att de olika karaktärsdragen hade en viss påverkan på cyklisternas stabilitet men i synnerhet på den självuppskattade cykelförmåga när de var alkoholpåverkade. Ca hälften av de berusade (de med hög riskbenägenhet) skattade att deras cykelförmåga inte försämrades. 

Alkohol påverkar cyklisters stabilitet, kognitiva prestation och självuppskattade cykelförmåga för alla grupper (olika karaktärsdrag). Olika individuella karaktärsdrag är viktiga eftersom de påverkar självreglerande beteenden där vissa individer bedömer att de kan cykla säkert även när de uppvisar sämre stabilitet och minskad kognitiv förmåga. I synnerhet är det individer med högre riskbenägenhet som tror (felaktigt) att de kan cykla på ett säkert sätt. 

Background and purpose: Parkinson's disease (PD) and multiple sclerosis (MS) can impair driving. However, we lack evidence on car accidents associated with these diseases. The aims of this study were to examine what types of car accident were associated with drivers with PD and MS, compared to individuals with ulcerative colitis (UC; the comparison group), and to evaluate the occurrence of car accidents in relation to years since diagnosis.

Methods: This retrospective nationwide, registry-based study included drivers involved in car accidents between 2010 and 2019, based on the Swedish Traffic Accident Data Acquisition database. Data on pre-existing diagnoses were retrieved retrospectively from the National Patient Registry. Data analyses included group comparisons, time-to-event analysis, and binary logistic regression.

Results: In total, 1491 drivers, including 199 with PD, 385 with MS, and 907 with UC, were registered to have been involved in a car accident. The mean time from diagnosis to the car accident was 5.6 years for PD, 8.0 years for MS, and 9.4 years for UC. Time to car accident since diagnosis differed significantly (p < 0.001) among groups (adjusted for age). Drivers with PD had more than twice the odds of a single-car accident than drivers with MS or UC, but no differences were observed between MS and UC.

Conclusions: Drivers with PD were older and experienced the car accident within a shorter timeframe after disease diagnosis. Although several factors may cause a car accident, fitness to drive could be more thoroughly evaluated for patients with PD by physicians, even early after the diagnosis.

Syftet med studien har varit att belysa omfattningen av bältesanvändningen idag, omfattningen av information om att bälte ska användas och att förstå resenärernas incitament att använda bälte, och med det som utgångspunkt föreslå åtgärder för att öka användningen av bälte vid resa med buss.

Metoder som använts är observationsstudie av bältesanvändning hos passagerare och bussförare, samt förekomst av förarens utrop om bältesanvändning. Arbetet omfattar även diskussioner i fokusgrupp med resenärer och förare, samt en webbenkät. Resultaten från observationsstudien visade att bältesanvändningen bland passagerare var 92 % i beställningstrafik, 50 % i kommersiell linjetrafik och 27 % i regional linjetrafik. Förarnas användande var på motsvarande sätt 100% i beställningstrafik, 79 % i kommersiell linjetrafik och 85 % i regional linjetrafik. Slutsatsen blir att åtgärder behövs för att öka användandegraden, särskilt i linjetrafiken.

I observationsstudien tillfrågades förare om de utropat att bälte ska tas på och passagerare tillfrågades om de blivit upplysta om att bältet ska tas på. I beställningstrafiken var det 86 % som erfarit utrop, i kommersiell linjetrafik var det 61 % och i regional linjetrafik var det 19 %. Slutsatsen blir att det framförallt i linjetrafiken finns stora brister i informationen om att ta på bältet, vilket bör åtgärdas.

Beslutet att använda bälte eller inte är individuellt. Faktorer som hur gammal du är, vilken erfarenhet du har av säkert bussåkande, på vilken typ av väg du reser, när du reser och hur du ser på säkerhet rent allmänt spelar en roll.

In 2018, the Forum of European Road Safety Research Institutes (FERSI) published a report on automated driving (AD) from a road safety point of view, prepared by a dedicated FERSI Working Group with experts from eleven European countries. The group identified 23 high priority concerns or questions, clustered into four categories, to ensure that connected AD and co-operative ITS successfully contribute to a smart, green, and integrated transport system which at the same time is a safe transport system. The discussions resulted in ten principles to be fulfilled in order to optimise the safety effects of AD. Even if these principles may seem straightforward, the underlying questions are complex, and the identification and realisation of cost-efficient and effective solutions will require considerable effort. Many strong industrial and political driving forces exist, but so far improving road safety seems to get insufficient priority. FERSI therefore recommends a number of focused actions.

This chapter will cover some of the issues mentioned by European Road Transport Research Advisory Council (ERTRAC) and has its starting point in the knowledge and experience from four different EU-funded projects dealing with automation and human factors. It might be expected that there is no difference in how human factors should be considered in relation to automation depending on the country it is used in. However, there are reasons to believe that there are differences in understanding and in acceptance of new functions depending on experience or not from modern vehicles with, for example integrated driver support systems. This chapter has its starting point mainly from work done in Europe, which may be considered to be generic and valid for other countries in the world with the same type of car fleets. The focus will be on challenges covering: the need to have an adaptive Human-Machine Interface (HMI) to achieve trust and acceptance in relation to automated functionalities and system, the importance of considering different driver states and finally the evaluations of automated systems.

Denna rapport presenterar studier och experiment inom REDO-projektet samt resultat ifrån dessa. Studierna är utförda mellan december 2019 och februari 2023 och rapporten täcker fem huvudämnen: 1) den effektlatens och siktvinkel har på körprestanda; 2) feedback och kontroll vid fjärrkörning; 3) uppkoppling samt mobilnätsstöd för fjärrstyrning; 4) videoöverföring för fjärrkörning; och 5) lagar och föreskrifter gällande fjärrstyrning. Innehållet i denna rapport avser att täcka tekniska detaljer och fynd inom samtliga av dessa ämnen, den är dock inte avsedd för att innehålla samtliga detaljer och resultat som redan har publicerats som vetenskapliga artiklar. Denna rapport bör ses som ett komplement till tidigare publicerade resultat.

Purpose: This paper aims to explore whether drivers would adapt their behavior when they drive among automated vehicles (AVs) compared to driving among manually driven vehicles (MVs).Understanding behavioral adaptation of drivers when they encounter AVs is crucial for assessing impacts of AVs in mixed-traffic situations. Here, mixed-traffic situations refer to situations where AVs share the roads with existing nonautomated vehicles such as conventional MVs.

Design/methodology/approach: A driving simulator study is designed to explore whether such behavioral adaptations exist. Two different driving scenarios were explored on a three-lane highway: driving on the main highway and merging from an on-ramp. For this study, 18 research participants were recruited.

Findings: Behavioral adaptation can be observed in terms of car-following speed, car-following time gap, number of lane change and overall driving speed. The adaptations are dependent on the driving scenario and whether the surrounding traffic was AVs or MVs. Although significant differences in behavior were found in more than 90% of the research participants, they adapted their behavior differently, and thus, magnitude of the behavioral adaptation remains unclear.

Originality/value: The observed behavioral adaptations in this paper were dependent on the driving scenario rather than the time gap between surrounding vehicles. This finding differs from previous studies, which have shown that drivers tend to adapt their behaviors with respect to the surrounding vehicles. Furthermore, the surrounding vehicles in this study are more “free flow'” compared to previous studies with a fixed formation such as platoons. Nevertheless, long-term observations are required to further support this claim.

Cut-in situations occurs when a vehicle intentionally changes lane and ends up in front of another vehicle or in-between two vehicles. In such situations, having a method to indicate the collision risk prior to making the cut-in maneuver could potentially reduce the number of sideswipe and rear end collisions caused by the cut-in maneuvers. This paper propose a new risk indicator, namely cut-in risk indicator (CRI), as a way to indicate and potentially foresee collision risks in cut-in situations. As an example use case, we applied CRI on data from a driving simulation experiment involving a manually driven vehicle and an automated platoon in a highway merging situation. We then compared the results with time-to-collision (TTC), and suggest that CRI could correctly indicate collision risks in a more effective way. CRI can be computed on all vehicles involved in the cut-in situations, not only for the vehicle that is cutting in. Making it possible for other vehicles to estimate the collision risk, for example if a cut-in from another vehicle occurs, the surrounding vehicles could be warned and have the possibility to react in order to potentially avoid or mitigate accidents.

Platooning refers to a group of vehicles that--enabled by wireless vehicle-to-vehicle (V2V) communication and vehicle automation--drives with short inter-vehicular distances. Before its deployment on public roads, several challenging traffic situations need to be handled. Among the challenges are cut-in situations, where a conventional vehicle--a vehicle that has no automation or V2V communication--changes lane and ends up between vehicles in a platoon. This paper presents results from a simulation study of a scenario, where a conventional vehicle, approaching from an on-ramp, merges into a platoon of five cars on a highway. We created the scenario with four platooning gaps: 15, 22.5, 30, and 42.5 meters. During the study, the conventional vehicle was driven by 37 test persons, who experienced all the platooning gaps using a driving simulator. The participants' opinions towards safety, comfort, and ease of driving between the platoon in each gap setting were also collected through a questionnaire. The results suggest that a 15-meter gap prevents most participants from cutting in, while causing potentially dangerous maneuvers and collisions when cut-in occurs. A platooning gap of at least 30 meters yield positive opinions from the participants, and facilitating more smooth cut-in maneuvers while less collisions were observed.

I ett föränderligt klimat där allt större krav ställs på väghållare och vinterdriftsentreprenörer att åstadkomma en för trafikanterna acceptabel vintersdriftstandard samtidigt som de ekonomiska resurserna blir alltmer begränsade, ökar behoven av kostnadseffektiva metoder. Prognosstyrd dynamisk vägdrift har visat sig kunna leda till en ökad produktivitet då väglagsprognoser integreras med ruttoptimering. 

Ett sätt att vidareutveckla väglagsprognoserna är att veta hur mycket salt som behövs på vägen, eller mer exakt, hur mycket salt finns kvar? Om det redan finns salt på vägen, behöver du inte sprida hela mängden, det kan räcka med hälften eller ännu mindre. 

Restsaltmätningar har gjorts under tre vintersäsonger vid Testsite E18. Platsen valdes eftersom den är utrustad med flera olika sensorer, monterade över, bredvid och i vägen. Salt mättes var trettionde centimeter tvärs över vägens två körfält. Av 9 mätningar var det bara 5 tillfällen med salt varav två av dem saltades enbart för våra mätningar, kvar var tre mätningar med vinterförhållanden. Alla mätningar som gjordes jämfördes med sensorer monterade på testplatsen för att jämföra hur väl en sensor representerar vägytan. Det visade sig att det generellt var väldigt låga saltvärden från de monterade sensorerna jämfört med de manuella mätningarna.

Cutting-edge sensors and devices are increasingly deployed within urban areas to make-up the fabric of transmission control protocol/internet protocol connectivity driven by Internet of Things (IoT). This immersion into physical urban environments creates new data streams, which could be exploited to deliver novel cloud-based services. Connected vehicles and road-infrastructure data are leveraged in this article to build applications that alleviate notorious parking and induced traffic-congestion issues. To optimize the utility of parking lots, our proposed SmartPark algorithm employs a discrete Markov-chain model to demystify the future state of a parking lot, by the time a vehicle is expected to reach it. The algorithm features three modular sections. First, a search process is triggered to identify the expected arrival-time periods to all parking lots in the targeted central business district (CBD) area. This process utilizes smart-pole data streams reporting congestion rates across parking area junctions. Then, a predictive analytics phase uses consolidated historical data about past parking dynamics to infer a state-transition matrix, showing the transformation of available spots in a parking lot over short periods of time. Finally, this matrix is projected against similar future seasonal periods to figure out the actual vacancy-expectation of a lot. The performance evaluation over an actual busy CBD area in Stockholm (Sweden) shows increased scalability capabilities, when further parking resources are made available, compared to a baseline case algorithm. Using standard urban-mobility simulation packages, the traffic-congestion-aware SmartPark is also shown to minimize the journey duration to the selected parking lot while maximizing the chances to find an available spot at the selected lot.

Kopplingskrafterna hos fordonskombinationer är de krafter som helt styr vart efterföljande fordon tar vägen. Ett brott på en sådan koppling kan därför få förödande konsekvenser om det inträffar i trafik. För att minska risken för sådana händelser, ställer myndigheter krav på bärighet hos dessa kopplingar. Det nuvarande rättsliga kravet är baserat på en ISO-standard som anger de minsta kraftnivåer som kopplingarna ska tåla. Dessa krafter har härletts utifrån semi-empiriska antaganden och explicita uttryck finns angivna för fem olika fordonskombinationer. Denna rapport syftar till att utöka kravet på kopplingskrafterna för två nya fordonskombinationer som i en framtid kan bli lagliga på det allmänna vägnätet. På grund av uttrycken i ISO-standardens semiempiriska natur, måste validering utföras. En jämförande simulering av kopplingskrafterna för de två nya samt de i ISO standarden existerande utgör en del i valideringen. En rimlighetskontroll av resultatet av uttrycken med existerande kopplingar på marknaden utgör den andra delen av valideringen. Valideringen visar att uttrycken ger rimliga krav som är i linje med vad ISO-standarden ger för existerande fordonskombinationer. Detta innebär att de kan användas som grund för framtida lagkrav för dessa fordonskombinationer. Ytterligare undersökningar av välgrundade, deducerade krav bör dock utföras för att säkerställa säkerhetsmarginaler och reducera empirin.

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

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

Maritime user interfaces for ships’ bridges are highly dependent on the context in which they are used, and rich maritime context is difficult to recreate in the early stages of user-centered design processes. Operations in Arctic waters where crews are faced with extreme environmental conditions, technology limitations and a lack of accurate navigational information further increase this challenge. There is a lack of research supporting the user-centered design of workplaces for hazardous Arctic operations. To meet this challenge, this paper reports on the process of developing virtual reality-reconstructed operational scenarios to connect stakeholders, end-users, designers, and human factors specialists in a joint process. This paper explores how virtual reality-reconstructed operational scenarios can be used as a tool both for concept development and user testing. Three operational scenarios were developed, implemented in a full mission bridge simulator, recreated in virtual reality (VR), and finally tested on navigators (end-users). Qualitative data were captured throughout the design process and user-testing, resulting in a thematic analysis that identified common themes reflecting the experiences gained throughout this process. In conclusion, we argue that operational scenarios, rendered in immersive media such as VR, may be an important and reusable asset when supporting maritime design processes and in maritime training and education. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.

Maritime navigation is a complex task involving the acquisition, analysis, and interpretation of information using seamanship, professional knowledge, and technology. As the maritime industry transitions towards maritime autonomous surface ships (MASS), there is an increasing gap between the operator and the technology. This paper explores a collision avoidance decision support system for navigation from the navigator's perspective. The system, developed by Wärtsilä, is called Advanced Intelligent Manoeuvring (AIM) and can generate suggestions for course or speed alterations based on data from surrounding traffic. Nineteen Swedish navigators completed three ship traffic scenarios with and without decision support. Qualitative data were collected using interviews and analysed with thematic analysis. The results show that the participants perceive the decision support system as an advisory tool to visualise how traffic situations could unfold, a task currently difficult for most navigators. This paper discusses the present and near future of maritime navigation, highlighting the benefits of automation, while remaining vigilant about the potential dangers.

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

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

Modern-day marine pilots are a competent and experienced workforce. They are highly skilled navigators that support the merchant fleet in transiting through challenging sea areas and rivers, as well as in the navigation in and out of ports. In this study, Applied Cognitive Task Analysis (ACTA) was used to pursue a deeper understanding of expertise and tacit or procedural knowledge that experts rely on and exhibit, mostly in safety-critical situations. ACTA is a structured interview method, which relies on three distinct phases: a task diagram, a knowledge audit and a simulation interview. In this article, results from the first two interview steps are presented to show the intricate complexity of pilotage and building blocks of expertise within marine pilotage. A total of eight experienced pilots from two different port areas in Sweden were interviewed. The results show that there are large differences in how pilotage is conducted in the two areas with regards to both tasks, knowledge and understanding of the service as such. Further, despite recognizing maneuvering as cognitively demanding, the pilots emphasized social skills and learning on the job as key elements of expertise. Conclusions drawn from the ACTA structure highlight the mentally and socially complex task that piloting is, and that the pilots use great discernment and acuity when processing verbal and non-verbal input, as well as physical human and vessel movements. 

The main objective of this paper is to develop a readiness index model that can serve as an analytical tool for exploring the achievements of the electrification of transportation systems. We have applied this readiness index model to evaluate the readiness positioning of China, Norway, and Sweden towards transportation electrification. We have chosen these three countries as they represent diversity among countries adopting electric transportation system solutions. Our developed readiness index model has four key dimensions: technological readiness, political readiness, societal readiness, and economic readiness. The embeddedness of all four dimensions in one model provides a multi-perspective way of analyzing and evaluating the readiness levels of countries moving towards transforming their transportation system. Therefore, we named the model a “multidimensional readiness index”. Our main conclusions are that political processes and decisiveness are the most important factors, followed by societal needs and economic ability, with the current technology as the fourth. Without the participation of dedicated and determined political decision makers, the other three factors are challenging to obtain. Political decision makers need to facilitate economic means to support the transformation in society and affected industries to balance the economic disadvantages of the electrically powered vehicle systems until they pass the cost disadvantage turning point. The development of relevant technology is no longer the significant barrier it was at the beginning of this transformation about 20 years ago. The technology for electrically powered transportation systems and devices is widely available now, although it is continuously evolving and being improved. Associated industries cannot be expected to initiate, finance, take risks, and take the lead in this global societal transformation without clear and strong political support.

Globally, the transportation system is transforming from a fossil-based to an electrification system. Some countries are leading in the transformation process. Some countries are rapidly catching up to become market leaders in developing and introducing new techniques and equipment that support the transformation process in their countries. In contrast, others are still relying on their old fossil-based system or could not have enough understanding of how to deal with this complex transformation of the transportation system.

The electrification of the transportation system is not an isolated system that can be handled as a single technological element. It is a group of multiple technologies, political, societal, and economic sub-systems each of these sub-systems is embedded in each other, forming the whole system. Therefore, it is important to see and manage the system from a holistic perspective to transform the transportation electrification system efficiently. We have selected eight countries from three different continents – Asia (China, India), Australia, which is a country and continent, and Europe (Germany, Norway, Slovenia, Sweden, and the UK) to explore the transformational process of transportation electrification based on each countries’ conditions. We have chosen these continents as they are diversified in adopting transportation electrification system solutions.

Our main conclusions are that the political processes and political decisiveness are the most important, followed by the societal and economic, with technology as the fourth. The other three are difficult to obtain without dedicated and determined political decision-makers. Political decision-makers need to use economic means to support the transformation in society and industry to balance the economic disadvantage of electric systems until they pass the cost disadvantage turning point. Technology is no longer a significant barrier as it was about 20 years ago. Now, technology is available, although it can be improved. The important part is to understand how to utilize the existing technology efficiently to transform the old fossil-based transportation system into new electrification of the transportation system. Without clear and strong political support, the industry cannot be expected to initiate, finance, take risks, and take the lead in this global societal transformation.

The main objective of this paper is to develop a readiness index model that can serve as an analytical tool for exploring the achievements of electrification of transportation systems. We have applied this readiness index model to evaluate the readiness positioning of China, Norway, and Sweden towards transport electrification. We have chosen these three countries as they represent diversity among countries that are in the process of adopting electrified transport system solutions. Our developed readiness index model has four key dimensions, technological readiness, political readiness, societal readiness, and economic readiness. The embeddedness of all four dimensions in one model provides a multi-perspective way of analyzing and evaluating the readiness levels of countries moving towards transforming the transportation system. Therefore, we named the model a “multidimensional readiness index.”

The electric road system is an emerging concept in this modern era. The advancement of technology has made it possible to give this concept a real shape (electric road system). However, the energy provided to the electric roads is still produced by non-renewable energy sources, which are completely unhealthy and harmful for society. Furthermore, the traditional grid is not suited to integrate with decentralized/localized energy generation and distribution systems. It is an ineffectual and environmentally extravagant system. Therefore, the preliminary contribution of this research is to introduce a decentralized/localized energy generation system based on renewable energy sources and energy distribution to electric roads through the emerging technology of microgrid and smart grid systems, which have the capability to integrate with renewable energy sources easily. Thus, producing electricity with renewable energy sources is environmentally friendly, less expensive, and available without charges. However, each source of energy has some environmental impacts and cost differences. A brief description of the environmental and cost impact of renewable energy sources (wind, solar) is also presented.

OBJECTIVE: This paper aims to describe and test novel computational driver models, predicting drivers' brake reaction times (BRTs) to different levels of lead vehicle braking, during driving with cruise control (CC) and during silent failures of adaptive cruise control (ACC).

BACKGROUND: Validated computational models predicting BRTs to silent failures of automation are lacking but are important for assessing the safety benefits of automated driving.

METHOD: Two alternative models of driver response to silent ACC failures are proposed: a looming prediction model, assuming that drivers embody a generative model of ACC, and a lower gain model, assuming that drivers' arousal decreases due to monitoring of the automated system. Predictions of BRTs issued by the models were tested using a driving simulator study.; RESULTS: The driving simulator study confirmed the predictions of the models: (a) BRTs were significantly shorter with an increase in kinematic criticality, both during driving with CC and during driving with ACC; (b) BRTs were significantly delayed when driving with ACC compared with driving with CC. However, the predicted BRTs were longer than the ones observed, entailing a fitting of the models to the data from the study.

CONCLUSION: Both the looming prediction model and the lower gain model predict well the BRTs for the ACC driving condition. However, the looming prediction model has the advantage of being able to predict average BRTs using the exact same parameters as the model fitted to the CC driving data.

APPLICATION: Knowledge resulting from this research can be helpful for assessing the safety benefits of automated driving.

Kunskapen om cyklisters beteende i förhållande till trafikregler men också vad som styr samspelet med andra trafikanter är bristfällig och behöver därför förbättras. Syftet med detta projekt var därför att kartlägga och studera samband och underliggande faktorer gällande regelkunskap, regelefterlevnad och informella regler bland cyklister. Deltagarna i studien var 612 personer mellan 18 och 74 år från Göteborg, Linköping och Stockholm och rekryterades genom en webbpanel. Personerna fick svara på en enkät där de tillfrågades om bakgrund, syn på sig själva som cyklister, egen regelefterlevnad, syn på andras regelefterlevnad, kunskap om regler och om faktorer som påverkar intentionen att bryta mot regler i trafiken.

Resultaten från studien visade att deltagarnas regelkunskap var relativt god, i varje fall när det gäller beteenden som är förbjudna. De deltagare som trodde att ett visst beteende var förbjudet svarade även att de utförde detta i mindre utsträckning. Cyklister som uppgett att de vill komma fram så fort som möjligt tenderade att välja flexiblare färdvägar (till exempel cyklade på övergångsställe, trottoar/gångbana och bilväg), oavsett om det var tillåtet eller inte, och uppgav i större utsträckning att det var vanligt att de lät bli att stanna vid rödljus och stopplikt än vad de långsammare cyklisterna gjorde. Cykelöverfarter och andra korsningspunkter, övergångsställen, trottoarer och cirkulationsplatser togs upp som exempel på platser/situationer där reglerna ansågs vara oklara. Upplevd kontroll och attityd påverkade intentionen att agera ovarsamt i tre hypotetiska scenarier som beskrev hur andra trafikanter fick väja eller bromsa för att undvika att kollidera med cyklisten. Detta innebär att de som hade för avsikt att bete sig på det angivna sättet ansåg att det var lätt och tämligen ofarligt, men också att det var både rätt och bra. Den viktigaste faktorn var dock om man utfört beteendet tidigare eller ej vilket i sin tur kan ha förstärkt denna uppfattning om inget allvarligt inträffat.

Obehöriga spårbeträdanden är olagliga, vållar stora förseningar på järnvägen och innebär ett allvarligt arbetsmiljöproblem för tågförarna. En del obehöriga spårbeträdanden leder dessutom till personpåkörningar, vilket står för den största andelen dödsfall inom järnvägen. Vissa stationer har omfattande problem med obehöriga spårbeträdanden och personpåkörningar och därför är riktade åtgärder mot stationsområden viktiga.

Syftet med projektet var att:

• studera tryggheten och säkerheten på de tre pendeltågsstationerna Järna, Upplands Väsby och Årstaberg innan någon åtgärd genomförts och studera resenärers och personals förslag på vad som kan förbättras,

• utvärdera de fysiska åtgärder som Trafikverket genomförde på dessa stationer, under förutsättning att åtgärderna implementerades under projektets tidsram (endast Järna station uppfyllde detta kriterium),

• utvärdera de implementerade åtgärderna på Stockholms södra station.

I projektet genomfördes strukturerade observationer, enkätstudier med resenärer och personal, intervjuer med personal, analys av händelser som inkommit till SL:s trygghetscentral, databasanalys över antal obehöriga spårbeträdanden och personpåkörningar samt videoanalys över antal obehöriga i spår.

Resultaten visar att det skett en signifikant minskning av antal obehöriga spårbeträdanden/personpåkörningar på Järna station efter att de fysiska åtgärderna med staket, nya hajtänder, varningsskyltar och klistermärken implementerades. Vid Upplands Väsby och Årstaberg skedde ingen minskning av antal händelser under samma tidsperiod, vilket tyder på att minskningen i Järna beror på något annat än en allmän trend.

Vi fann även en stor och signifikant minskning av antal obehöriga spårbeträdanden på Stockholms södra station, samt en signifikant minskning av antalet personpåkörningar på stationen och förseningar på grund av obehöriga i spår, personpåkörningar och suicidhändelser. Detta indikerar att åtgärden med längsgående staket i plattformsände (inklusive pyramidmattor, hajtänder och skyltar) har haft en effekt.

De implementerade åtgärderna på Järna station och Stockholms södra station har varit enkla och relativt billiga samtidigt som resultaten tyder på att de haft effekt. Denna typ av åtgärder, som dessutom kan användas i kombination med varandra, är en viktig strategi för att skyndsamt minska antalet obehöriga spårbeträdanden och personpåkörningar.

Obehöriga spårbeträdanden kan leda till allvarliga personskador och är dessutom mycket punktlighetsstörande för järnvägssystemet. En del stationer har omfattande problem med obehöriga i spår. Att rikta åtgärder mot stationsområden är därför viktigt för att minska antalet skadade och omkomna i järnvägssystemet och för att öka punktligheten. Inom det branschövergripande arbetet Tillsammans för Tåg i Tid pekade man ut pendeltågsstationerna Årstaberg, Upplands Väsby och Järna som belastade platser.

Syften med den här studien var att:

• studera säkerheten på de tre stationerna ovan samt att studera resenärers och personals förslag på vad som kan förbättras på dessa stationer. Vi studerade även tryggheten på stationerna.
• Utvärdera de fysiska åtgärder som Trafikverket genomför på de tre stationerna under projektets tidsram. Även Södra station studerades.

I denna presentation kommer endast resultat från det första syftet presenteras. 

I projektet har följande aktiviteter genomförts:

• Platsbesök på stationerna, inklusive samtal med personal på plats, för att dokumentera utformning av och brister på stationerna.
• Analys av data över antal obehöriga spårbeträdanden och påkörningar vid dessa stationer samt förseningar som en följd av dessa händelser.
• Analys av händelser som inkommit till Trygghetscentralen gällande de tre stationerna.
• Resenärsenkät kring upplevd trygghet, säkerhet samt information på de tre pendeltågsstationerna.
• Rekrytering skedde genom anslag på berörda stationer, annons på Facebook samt på Instagram.
• Personalenkät (med liknande innehåll som i resenärsenkäten) riktad till lokalvårdare, ordningsvakter och stationsvärdar (spärrvakter).
• Intervjuer med pendeltågsförare, stationschefer och entreprenörer.

Omkring 90% av de deltagande resenärerna svarade att de visste att det är olagligt att befinna sig i spårområdet redan innan de deltog i studien. I Årstaberg upplevde resenärerna att stationen var mindre säker (med tanke på risken att ramla ner på spåret) än vad man gjorde i Järna. I övrigt var ingen skillnad i upplevd säkerhet mellan stationerna. När det gäller hur trygga stationerna upplevdes av resenärerna (med avseende på risken för rån och överfall) var det ingen skillnad mellan stationerna på dagtid. På kvällar/nätter upplevdes dock Upplands Väsby som mer otrygg än Årstaberg.

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

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

Driving simulators are established tools used during automotive development and research. Most simulators use either monitors or projectors as their primary display system. However, the emergence of a new generation of head-mounted displays has triggered interest in using these as the primary display type. The general benefits and drawbacks of head-mounted displays are well researched, but their effect on driving behavior in a simulator has not been sufficiently quantified.

This article presents a study of driving behavior differences between projector-based graphics and head-mounted display in a large dynamic driving simulator. This study has selected five specific driving maneuvers suspected of affecting driving behavior differently depending on the choice of display technology. Some of these maneuvers were chosen to reveal changes in lateral and longitudinal driving behavior. Others were picked for their ability to highlight the benefits and drawbacks of head-mounted displays in a driving context.

The results show minor changes in lateral and longitudinal driver behavior changes when comparing projectors and a head-mounted display. The most noticeable difference in favor of projectors was seen when the display resolution is critical to the driving task. The choice of display type did not affect simulator sickness nor the realism rated by the subjects.

Driving requires a series of cognitive abilities, many of which are affected by age and medical conditions. The psychosocial importance of continued driving ushers the need for valid measurements in fitness-to-drive assessments. A driving simulator test could prove useful in these assessments, having greater face validity than other off-road tests and being more cost-effective and safer than ordinary on-road testing. The aim of this study was to validate a driving simulator test for assessment of cognitive ability in fitness-to-drive assessments.

The study included 67 healthy participants. Internal consistency of the simulator subtests was estimated. A correlation analysis between results on the simulator and the cognitive tests Trail Making Test (TMT) A and B and the Useful field of View test (UFOV) and multiple regression analysis were conducted. Finally, a comparison of results between age groups (>65 years) and (<65 years) was done.

Performance based standards (PBS) is an effective regulator policy which can address variation complexity in vehicle combinations. This paper investigates aspects of using computer simulation and mathematical models to assess the performance of vehicle combinations in low speed manoeuvring, and in particular roundabouts. A set of 22 vehicle combinations, including existing conventional heavy vehicles as well as prospective high capacity vehicles, is used to study the effects of turn angle and road surface conditions on the friction demand and swept path measures. Simulation results suggest that the friction demand measure is dependent on the available grip. This makes it hard to interpret and may not be suitable in the PBS framework. The swept path measure is relatively unaffected by friction levels, and can hence be calculated with simple and robust expressions not considering the road interaction. However, turn angle affects the swept path measure considerably, and should be addressed when designing the PBS scheme implementation into the legislations.

Flera olika typer av tunga fordonskombinationer är tillåtna på det svenska vägnätet. En vanlig kombination är dragbil och påhängsvagn med en total längd på 16,5 meter. Den lagliga begränsningen av kombinationens totala längd har lett till att en kort dragbil används för att ge plats för mer gods på släpvagnen. Det finns en oro för att dragbilens korthet kan få en negativ konsekvens för trafiksäkerheten och förmågan att klara backar. Dragbilens korta hjulbas och obalansen i vikt mellan dragbilen och påhängsvagnen skulle kunna utgöra ett problem när du bromsar och svänger. 

Denna studie är beställd av Transportstyrelsen för att undersöka trafiksäkerhetsaspekterna och problem med backstigning för vissa tunga fordonskombinationer. Den oro som beskrivs undersöks ur ett fordonsdynamiskt perspektiv för de aktuella fordonskombinationerna och jämförs med andra vanliga fordonskombinationer genom en simuleringsstudie. 

En uppsättning kombinationer av dragbilar och påhängsvagnar har simulerats under extrema förhållanden och manövrar för att undersöka fordonets svar och dess beroenden på dragbilens axelavstånd, kopplingslängd, femte hjulsmörjning och vägytans förhållanden. Där det är meningsfullt gjordes en jämförelse med en nordisk kombination (lastbil och full släpvagn) samt med en B-dubbelkombination (dragbil, länkvagn och påhängsvagn). 

Det samlade resultatet av simuleringsstudien är att kombinationen av dragbil och påhängsvagn är en stabil kombination, som överträffar de längre och tyngre kombinationer av nordiska och B-dubblar i alla uppmätta situationer och manövrar där jämförelsen är meningsfull. Dragbilens hjulbas och kopplingsavstånd verkar dessutom ha en mycket liten effekt på fordonskombinationernas prestanda.

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

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

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

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

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

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

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

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

Denna slutrapport redogör för resultatet av projektet: AutoMon Del I—Automatisk trafikövervakning genom AI i svenska farvatten (TRV2019/95873). Projektägare är Linköpings universitet och genomförts tillsammans med Sjöfartsverket, SAAB, VTI, och Luftfartsverket. Vi kommer i denna rapport redogöra för resultaten samt diskutera framtida utmaningar med konceptet AutoMon. Syftet med AutoMon är att undersöka och belysa problemområdet automatiserad trafikövervakning genom att implementera en AI-demonstrator för svenska farvatten, initialt med fokus på att detektera anomalier i trafiken, och där hanteringen (dvs. granskning och lösning) av problemsituationer lämnas över till en mänsklig operatör. Förekomsten av fartygsolyckor och -incidenter, med potentiellt stora konsekvenser för individ och miljö - utanför etablerade VTS-områden - visar på behovet av utökad övervakning av sjötrafiken i svenska farvatten för att möjliggöra proaktiva åtgärder för att minimera olycksrisker till sjöss. Forskningsprojektet undersöker hur en hög nivå av automation kan användas för att upptäcka och hantera trafikavvikelser på svenskt vatten samt ge möjlighet till s.k. situational awareness (lägesbild) över hela dess yta, samtidigt som stöd för centralt eller distribuerat beslutsfattande ges. Runt om i världen förekommer även manipulation av AIS-systemet och dess positionsangivelser; ett problem som sannolikt kommer att öka även i Sverige. Båda problemställningarna är globala, vilket ger hög relevans. Lösningar har högt värde där digitalisering och artificiell intelligens kan användas som medel för ökad sjösäkerhet (safety och cyber security).