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Anund, A., Ahlström, C., Fors, C. & Åkerstedt, T. (2018). Are professional drivers less sleepy than non-professional drivers?. Scandinavian Journal of Work, Environment and Health, 44(1), 88-95
Open this publication in new window or tab >>Are professional drivers less sleepy than non-professional drivers?
2018 (English)In: Scandinavian Journal of Work, Environment and Health, ISSN 0355-3140, E-ISSN 1795-990X, Vol. 44, no 1, p. 88-95Article in journal (Refereed) Published
Abstract [en]

Objective It is generally believed that professional drivers can manage quite severe fatigue before routine driving performance is affected. In addition, there are results indicating that professional drivers can adapt to prolonged night shifts and may be able to learn to drive without decreased performance under high levels of sleepiness. However, very little research has been conducted to compare professionals and non-professionals when controlling for time driven and time of day.

Method The aim of this study was to use a driving simulator to investigate whether professional drivers are more resistant to sleep deprivation than non-professional drivers. Differences in the development of sleepiness (self-reported, physiological and behavioral) during driving was investigated in 11 young professional and 15 non-professional drivers.

Results Professional drivers self-reported significantly lower sleepiness while driving a simulator than nonprofessional drivers. In contradiction, they showed longer blink durations and more line crossings, both of which are indicators of sleepiness. They also drove faster. The reason for the discrepancy in the relation between the different sleepiness indicators for the two groups could be due to more experience to sleepiness among the professional drivers or possibly to the faster speed, which might unconsciously have been used by the professionals to try to counteract sleepiness.

Conclusion Professional drivers self-reported significantly lower sleepiness while driving a simulator than non-professional drivers. However, they showed longer blink durations and more line crossings, both of which are indicators of sleepiness, and they drove faster.

Place, publisher, year, edition, pages
SCANDINAVIAN JOURNAL WORK ENVIRONMENT & HEALTH, 2018
Keywords
Fatigue (human), Driver, Professional category, Simulator (driving), Speed, Behaviour
National Category
Applied Psychology
Research subject
80 Road: Traffic safety and accidents, 841 Road: Road user behaviour
Identifiers
urn:nbn:se:vti:diva-12735 (URN)10.5271/sjweh.3677 (DOI)000418916600010 ()29018866 (PubMedID)2-s2.0-85040066980 (Scopus ID)
Available from: 2018-05-17 Created: 2018-05-17 Last updated: 2018-06-12Bibliographically approved
Abtahi, F., Anund, A., Fors, C., Seoane, F. & Lindecrantz, K. (2018). Association of drivers’ sleepiness with heart rate variability: A pilot study with drivers on real roads. In: IFMBE Proceedings: . Paper presented at Joint Conference of the European Medical and Biological Engineering Conference, EMBEC 2017 and Nordic-Baltic Conference on Biomedical Engineering and Medical Physics, NBC 2107, 11 June 2017 through 15 June 2017 (pp. 149-152). Springer Verlag, 65
Open this publication in new window or tab >>Association of drivers’ sleepiness with heart rate variability: A pilot study with drivers on real roads
Show others...
2018 (English)In: IFMBE Proceedings, Springer Verlag , 2018, Vol. 65, p. 149-152Conference paper, Published paper (Refereed)
Abstract [en]

Vehicle crashes lead to huge economic and social consequences, and one non-negligible cause of accident is driver sleepiness. Driver sleepiness analysis based on the monitoring of vehicle acceleration, steering and deviation from the road or physiological and behavioral monitoring of the driver, e.g., monitoring of yawning, head pose, eye blinks and eye closures, electroencephalogram, electrooculogram, electromyogram and electrocardiogram (ECG), have been used as a part of sleepiness alert systems.

Heart rate variability (HRV) is a potential method for monitoring of driver sleepiness. Despite previous positive reports from the use of HRV for sleepiness detection, results are often inconsistent between studies. In this work, we have re-evaluated the feasibility of using HRV for detecting drivers’ sleepiness during real road driving. A database consists of ECG measurements from 10 drivers, driving during morning, afternoon and night sessions on real road were used. Drivers have reported their average sleepiness level by using the Karolinska sleepiness scale once every five minutes. Statistical analysis was performed to evaluate the potential of HRV indexes to distinguish between alert, first signs of sleepiness and severe sleepiness states. The results suggest that individual subjects show different reactions to sleepiness, which produces an individual change in HRV indicators. The results motivate future work for more personalized approaches in sleepiness detection.

Place, publisher, year, edition, pages
Springer Verlag, 2018
Keywords
Fatigue (human), Detection, Heart beat, Variability, Driver, ECG
National Category
Applied Psychology
Research subject
80 Road: Traffic safety and accidents, 84 Road: Road users
Identifiers
urn:nbn:se:vti:diva-11938 (URN)10.1007/978-981-10-5122-7_38 (DOI)2-s2.0-85021750920 (Scopus ID)9789811051210 (ISBN)
Conference
Joint Conference of the European Medical and Biological Engineering Conference, EMBEC 2017 and Nordic-Baltic Conference on Biomedical Engineering and Medical Physics, NBC 2107, 11 June 2017 through 15 June 2017
Available from: 2017-07-19 Created: 2017-07-19 Last updated: 2018-01-25Bibliographically approved
Ahlström, C., Anund, A., Fors, C. & Åkerstedt, T. (2018). Effects of the road environment on the development of driver sleepiness in young male drivers. Accident Analysis and Prevention, 112, 127-134
Open this publication in new window or tab >>Effects of the road environment on the development of driver sleepiness in young male drivers
2018 (English)In: Accident Analysis and Prevention, ISSN 0001-4575, E-ISSN 1879-2057, Vol. 112, p. 127-134Article in journal (Refereed) Published
Abstract [en]

Latent driver sleepiness may in some cases be masked by for example social interaction, stress and physical activity. This short-term modulation of sleepiness may also result from environmental factors, such as when driving in stimulating environments. The aim of this study is to compare two road environments and investigate how they affect driver sleepiness. Thirty young male drivers participated in a driving simulator experiment where they drove two scenarios: a rural environment with winding roads and low traffic density, and a suburban road with higher traffic density and a more built-up roadside environment. The driving task was essentially the same in both scenarios, i.e. to stay on the road, without much interaction with other road users. A 2 x 2 design, with the conditions rural versus suburban, and daytime (full sleep) versus night-time (sleep deprived), was used. The results show that there were only minor effects of the road environment on subjective and physiological indicators of sleepiness. In contrast, there was an increase in subjective sleepiness, longer blink durations and increased EEG alpha content, both due to time on task and to night-time driving. The two road environments differed both in terms of the demand on driver action and of visual load, and the results indicate that action demand is the more important of the two factors. The notion that driver fatigue should be countered in a more stimulating visual environment such as in the city is thus more likely due to increased task demand rather than to a richer visual scenery. This should be investigated in further studies.

Place, publisher, year, edition, pages
PERGAMON-ELSEVIER SCIENCE LTD, 2018
Keywords
Fatigue (human), Roadside, Stimulation, Attention, Simulator (driving), Impact study, Mental load
National Category
Applied Psychology
Research subject
80 Road: Traffic safety and accidents, 841 Road: Road user behaviour
Identifiers
urn:nbn:se:vti:diva-12812 (URN)10.1016/j.aap.2018.01.012 (DOI)000424963000015 ()29346084 (PubMedID)
Available from: 2018-04-05 Created: 2018-04-05 Last updated: 2018-06-11Bibliographically approved
Johansen, T. C. & Fors, C. (2018). Method description – assessment of road marking materials used in contracts: Nordic certification system for road marking materials. Linköping: Statens väg- och transportforskningsinstitut
Open this publication in new window or tab >>Method description – assessment of road marking materials used in contracts: Nordic certification system for road marking materials
2018 (English)Report (Other academic)
Alternative title[sv]
Metodbeskrivning – kontroll av vägmarkeringsmaterial som används i kontrakt : nordiskt certifieringssystem för vägmarkeringsmaterial
Abstract [en]

A Nordic certification system for road marking materials was introduced in 2015. In the first stage, the certification system applies to the countries of Denmark, Norway and Sweden. In these countries, a documented product approval will be required in order to use a road marking material on roads managed by the national road authorities. Product approval will be based on monitored and documented performance measurements of material samples applied on test fields on public roads.

In order to be able to assess whether the (approved) road marking materials that are specified in contracts with a national road authority correspond to the materials that are applied on the roads, an assessment system will be introduced. The present report describes this assessment system.

The assessment system prescribes that material samples shall be taken when road marking materials are applied on the roads. A selection of the samples will then be sent to an accredited laboratory for analysis. The report describes how the material samples are selected, collected and analysed, and how the result is reported. It also describes the contractor’s responsibilities related to sample collection and the required competences of the assessment organization.

Abstract [sv]

Ett nordiskt certifieringssystem för vägmarkeringsmaterial introducerades år 2015 och omfattar i ett första steg Danmark, Norge och Sverige. I dessa länder krävs (eller kommer inom kort att krävas) ett dokumenterat godkännande av vägmarkeringsmaterial som används på vägar som administreras av den statliga väghållaren. Detta godkännande baseras på funktionsmätningar på vägmarkeringar som har applicerats på provfält.

För att kunna kontrollera och följa upp att de (godkända) vägmarkeringsmaterial som har specificerats i kontrakt med en statlig väghållare stämmer överens med de material som sedan läggs ut på vägen, kommer ett kontrollsystem att införas. Föreliggande rapport beskriver detta kontrollsystem.

Kontrollsystemet innebär att materialprover tas i samband med att vägmarkeringsmaterial läggs ut på vägen. Ett urval av proverna skickas sedan till ett ackrediterat laboratorium för analys. Rapporten beskriver hur prover väljs ut, samlas in och analyseras, samt hur resultatet rapporteras. Den beskriver också entreprenörens skyldigheter i samband med provtagning och de kompetenser som krävs hos organisationen som utför kontrollen.

Place, publisher, year, edition, pages
Linköping: Statens väg- och transportforskningsinstitut, 2018. p. 24
Series
VTI notat ; 6A-2018
Identifiers
urn:nbn:se:vti:diva-12873 (URN)
Available from: 2018-04-09 Created: 2018-04-09 Last updated: 2018-04-13Bibliographically approved
Johansen, T. C., Fors, C. & Kjellman, E. (2018). Nordic certification of road marking materials in Denmark 2015–2017. Linköping: Statens väg- och transportforskningsinstitut
Open this publication in new window or tab >>Nordic certification of road marking materials in Denmark 2015–2017
2018 (English)Report (Other academic)
Alternative title[sv]
Nordisk certifiering av vägmarkeringsmaterial i Danmark 2015–2017
Abstract [en]

A Nordic certification system for road marking materials was introduced in 2015. In the first stage, the certification system applies to the countries of Denmark, Norway and Sweden. In these countries, a documented product approval will be required in order to use a road marking material on roads managed by the national road authorities. Product approval will be based on monitored and documented performance measurements of material samples applied on test fields on public roads.

The first round of material tests in Denmark started in autumn 2015. In all, 32 materials, out of which 24 were for certification and 8 for manufacturer’s internal test, were applied at the Danish test site in Hornbæk. In 2016, a new test site was established close to Gørlev, where another 22 materials were applied, 20 for certification and 2 for manufacturer’s internal test.

The present report documents the follow-up performance measurements that were carried out in 2017, i.e. one year follow-up measurements for materials applied in 2016 and two years follow-up measurements for materials applied in 2015. The performance parameters include the coefficient of retroreflected luminance (RL) under dry and wet conditions, the luminance coefficient under diffuse illumination (Qd), the friction, and the chromaticity in daylight.

Abstract [sv]

En nordisk certifiering av vägmarkeringsmaterial introducerades 2015 och avser i ett första steg Danmark, Norge och Sverige. I dessa länder kommer det att krävas ett dokumenterat godkännande av vägmarkeringsmaterial som används på vägar som administreras av den statliga väghållaren. Detta godkännande baseras på funktionsmätningar på vägmarkeringar som har applicerats i provfält.

En första testomgång i Danmark påbörjades hösten 2015. Totalt 32 material, varav 24 för certifiering och 8 för tillverkarnas interna test, applicerades på det danska provfältet i Hornbæk. År 2016 etablerades ett nytt provfält nära Gørlev, där ytterligare 22 material applicerades, 20 för certifiering och 2 för tillverkarnas interna test.

Föreliggande rapport redovisar resultaten från de uppföljande funktionsmätningar som gjordes 2017, det vill säga ettårsuppföljning av material som lades ut 2016 och tvåårsuppföljning av material som lades ut 2015. Funktionsmätningarna omfattar retroreflexion (RL) i torrt och vått tillstånd, luminanskoefficient (Qd), friktion och färg i dagsljus.

Place, publisher, year, edition, pages
Linköping: Statens väg- och transportforskningsinstitut, 2018. p. 41
Series
VTI rapport, ISSN 0347-6030 ; 963A
Identifiers
urn:nbn:se:vti:diva-12803 (URN)
Available from: 2018-03-20 Created: 2018-03-20 Last updated: 2018-03-20Bibliographically approved
Johansen, T. C., Fors, C. & Kjellman, E. (2018). Nordic certification of road marking materials in Norway and Sweden 2015–2017. Linköping: Statens väg- och transportforskningsinstitut
Open this publication in new window or tab >>Nordic certification of road marking materials in Norway and Sweden 2015–2017
2018 (English)Report (Other academic)
Alternative title[sv]
Nordisk certifiering av vägmarkeringsmaterial i Norge och Sverige 2015–2017
Abstract [en]

A Nordic certification system for road marking materials was introduced in 2015. In the first stage, the certification system applies to the countries of Denmark, Norway and Sweden. In these countries, a documented product approval will be required in order to use a road marking material on roads managed by the national road authorities. Product approval will be based on monitored and documented performance measurements of material samples applied on test fields on public roads.

The first round of material tests in Sweden started in May 2015. In all, 81 materials, out of which 78 were for certification and 3 for manufacturer’s internal test, were applied at the Swedish test site north of Sunne, in the west of Sweden. In 2016, another 72 materials were applied for certification at the Swedish test site.

The present report documents the follow-up performance measurements that were carried out in 2017, i.e. one-year follow-up measurements for materials applied in 2016 and two years follow-up measurements for materials applied in 2015. The performance parameters include the coefficient of retroreflected luminance (RL) under dry and wet conditions, the luminance coefficient under diffuse illumination (Qd), the friction, the chromaticity in daylight, and the chromaticity of retroreflected light (yellow materials, only).

Abstract [sv]

En nordisk certifiering av vägmarkeringsmaterial introducerades 2015 och avser i ett första steg Danmark, Norge och Sverige. I dessa länder kommer det att krävas ett dokumenterat godkännande av vägmarkeringsmaterial som används på vägar som administreras av den statliga väghållaren. Detta godkännande baseras på funktionsmätningar på vägmarkeringar som har applicerats i provfält.

En första testomgång i Sverige påbörjades i maj 2015. Totalt 81 material, varav 78 för certifiering och tre för tillverkarnas interna test, applicerades på det svenska provfältet norr om Sunne. År 2016 applicerades ytterligare 72 material på det svenska provfältet.

Föreliggande rapport dokumenterar resultaten från de uppföljande funktionsmätningar som gjordes 2017, det vill säga ettårsuppföljning av material som lades ut 2016 och tvåårsuppföljning av material som lades ut 2015. Funktionsmätningarna omfattar retroreflexion (RL) i torrt och vått tillstånd, luminanskoefficient (Qd), friktion, färg i dagsljus och färg i fordonsbelysning (för gula material).

Place, publisher, year, edition, pages
Linköping: Statens väg- och transportforskningsinstitut, 2018. p. 52
Series
VTI rapport, ISSN 0347-6030 ; 962A
Identifiers
urn:nbn:se:vti:diva-12802 (URN)
Available from: 2018-03-16 Created: 2018-03-16 Last updated: 2018-03-20Bibliographically approved
Fors, C., Johansen, T. C., Lundkvist, S.-O. & Nygårdhs, S. (2018). Nordic certification system for road marking materials: version 5:2018. Linköping: Statens väg- och transportforskningsinstitut
Open this publication in new window or tab >>Nordic certification system for road marking materials: version 5:2018
2018 (English)Report (Other academic)
Alternative title[sv]
Nordiskt certifieringssystem för vägmarkeringsmaterial : version 5:2018
Abstract [en]

A Nordic certification system for road marking materials was introduced in 2015. The system is based on documented performance measurements of material samples applied on test fields on public roads. From 2016, the certification system includes both flat (type I) and structured/profiled (type II) markings. Since 2017 the certification system also includes antiskid materials (a material with enhanced friction). From 2018 the certification system will also include temporary markings (Denmark only), and inlaid markings (Norway only).

Material tests are carried out at two test sites: one in Norway and one in Denmark. The tests fields are situated on public roads and the tested materials are thus exposed to real traffic conditions and to weather conditions representative for the Nordic countries. The materials are followed up by performance measurements during one or two years. The certification includes requirements on coefficient of retroreflected luminance RL under dry and wet conditions, luminance coefficient under diffuse illumination Qd, friction and colour coordinates. The number of wheel passages is measured at the test sites annually. The certification system includes material identification, which allows for future material sampling and analysis.

The certification system is based on the European standards EN 1824 Road marking materials Road trials, EN 1436 Road marking materials Road marking performance for road users, and EN 12802 Road marking materials Laboratory methods for identification.

The report describes the certification system and how it is applied in the Nordic countries. Procedures and methods that are used for application of materials and performance measurements are specified.

Abstract [sv]

Ett nordiskt certifieringssystem för vägmarkeringsmaterial introducerades under 2015. Systemet baseras på dokumenterade materialtester på provfält, där materialen certifieras utifrån hur många hjulpassager de klarar. Från och med 2016 omfattar certifieringssystemet både plana (typ I) och profilerade/våtsynbara (typ II) markeringar. År 2017 utökades certifieringssystem ytterligare till att även inkludera friktionsmaterial (material med förbättrad friktion). Från 2018 kommer certifieringssystemet även att inkludera temporära markeringar (endast Danmark), och nedfrästa markeringar (endast Norge).

Materialtester görs på två provfält: ett i Norge och ett i Danmark. Provfälten är placerade på allmän väg och materialen som testas är således exponerade för reell trafik samt för väderförhållanden representativa för de nordiska länderna. Materialen följs upp med funktionsmätningar under ett eller två år. Certifieringen omfattar krav på retroreflexion RL, luminanskoefficient Qd, friktion och färgkoordinater. Antalet hjulpassager materialen utsätts för mäts årligen. Certifieringssystemet inkluderar även materialidentifiering, vilket möjliggör senare stickprovskontroller vid entreprenader.

Certifieringssystemet baseras på europastandarderna EN 1824 Road marking materials Road trials, EN 1436 Road marking materials Road marking performance for road users, samt EN 12802 Road marking materials Laboratory methods for identification.

Rapporten beskriver hur certifieringssystemet fungerar och hur det tillämpas i de nordiska länderna. Vidare beskrivs de procedurer och metoder som används vid utläggning av material, samt vid mätning av materialens funktionsparametrar.

Place, publisher, year, edition, pages
Linköping: Statens väg- och transportforskningsinstitut, 2018
Series
VTI notat ; 12A-2018
Identifiers
urn:nbn:se:vti:diva-13101 (URN)
Available from: 2018-06-01 Created: 2018-06-01 Last updated: 2018-06-01Bibliographically approved
Nygårdhs, S., Fors, C., Carlson, A. & Ihlström, J. (2017). Kriterier för vägbelysning på statlig väg i och i anslutning till mindre tätorter på landsbygd: Resultat från litteraturstudie, intervjuer och projektmöte. Linköping: Statens väg- och transportforskningsinstitut
Open this publication in new window or tab >>Kriterier för vägbelysning på statlig väg i och i anslutning till mindre tätorter på landsbygd: Resultat från litteraturstudie, intervjuer och projektmöte
2017 (Swedish)Report (Other academic)
Alternative title[en]
Cristeria for road lighting on public roads in and around lightly populated rural areas : Results from literature review, interviews and project meeting
Abstract [sv]

Enligt nuvarande riktlinjer för väg- och gatubelysning ska vägar och gator inom tätort förses med stationär belysning, medan vägar utanför tätort normalt sett inte behöver ha belysning. Regelverket Vägar och gators utformning (VGU) är tvingande för det statliga vägnätet medan det är rådgivande för kommunala vägar och gator. Behovet av belysning på statlig väg utanför tätort har varit en källa till diskussion mellan Trafikverket och kommunerna.

Syftet med denna studie är att ta fram ett förslag på nya riktlinjer för när vägbelysning ska användas på statlig väg i och i anslutning till mindre tätorter på landsbygd. Detta har huvudsakligen gjorts genom litteratursammanställning av riktlinjer och vetenskapliga studier om trafikanters behov och vägbelysningens effekter samt genom intervjuer med belysningsansvariga i kommuner. En lista över tänkbara kriterier togs fram och diskuterades på möte med Sveriges Kommuner och Landstings (SKL:s) och Trafikverkets gemensamma projektgrupp för projektet ”Kriterier för belysning på statlig väg”. Deltagarna vid detta möte ansåg att nedanstående kriterier är intressanta att gå vidare med i en tillämpning.

En statlig väg i eller i anslutning till mindre tätort på landsbygd ska vara försedd med vägbelysning om:

  1. vägen går genom en tätort (enligt Statistiska Centralbyråns gällande definition)
  2. det finns en kommunal detaljplan eller byggnadsplan med en statlig genomfartsväg där det förekommer blandtrafik
  3. det förekommer inrättningar som genererar oskyddade trafikanter i närheten av vägen, till exempel skolor, kyrkor, samlingslokaler, idrottshallar, vårdcentraler, muséer, tågstationer, färjelägen eller liknande
  4. det förekommer gång- och cykelpassager eller hastighetsdämpande åtgärder längs vägen
  5. det förekommer pendlingshållplatser, inklusive tåg och båt 6. gällande ÅDT-krav i VGU är uppfyllda.
Abstract [en]

According to the prevailing road lighting guidelines, roads and streets in urban areas should be equipped with road lighting, while roads outside of urban areas normally do not need to be equipped with road lighting. Vägar och gators utformning (VGU) contains guidelines that are mandatory for public roads but advisory for municipality roads and streets. The need of road lighting on public roads outside of urban areas has been discussed between the road authorities, i.e. the Swedish Transport Administration and the municipalities.

The aim of this study is to produce a proposal of new criteria for use of road lighting on public roads in and in connection to smaller populated areas in the countryside. This has mainly been done by a literature review of guidelines and research studies about road users’ needs and the effect of road lighting, as well as through interviews with persons responsible for road lighting in Swedish municipalities. A list containing possible criteria was compiled and discussed at a meeting with the project group for the project “Kriterier för belysning på statlig väg”, which is a group with common members from Swedish Association of Local Authorities and Regions (SALAR) and Swedish Transport Administration. The participants at the meeting found the following criteria interesting to apply.

A public road on the countryside should be equipped with road lighting if:

  1. the road runs through an urban area
  2. there is a local plan where there is mixed traffic on a national arterial road
  3. there are establishments and services that generate vulnerable road users close by the road, e.g. schools, churches, community centers, gymnasiums, health care centers, museums, train stations, ferry quays or similar
  4. there are passages for pedestrians and cyclists or speed reducing measures along the road
  5. there are commuter stops, including train and boat
  6. prevailing requirements on AADT in VGU are fulfilled.
Place, publisher, year, edition, pages
Linköping: Statens väg- och transportforskningsinstitut, 2017. p. 43
Series
VTI notat ; 20-2017
National Category
Infrastructure Engineering
Identifiers
urn:nbn:se:vti:diva-11897 (URN)
Available from: 2017-07-03 Created: 2017-07-03 Last updated: 2017-07-03Bibliographically approved
Fors, C., Lundkvist, S.-O. & Englundh, S. (2017). Mobil mätning av vägbelysning. Linköping: Statens väg- och transportforskningsinstitut
Open this publication in new window or tab >>Mobil mätning av vägbelysning
2017 (Swedish)Report (Other academic)
Alternative title[en]
Mobile measurement of street lighting
Abstract [sv]

För de flesta typer av vägutrustningar finns regelverk som ställer funktionskrav. Exempelvis ska en vägmarkering ha en lägsta retroreflexion för att den ska ha tillräcklig synbarhet. Beträffande vägbelysning finns i Trafikverkets Krav för Vägar och Gators Utformning (VGU) flera olika funktionskrav, bland annat krav på tillåten bländning, krav på avskärmning, belysningsstyrka och den vägyteluminans som belysningen ger. På de allra flesta gator och vägar är luminanskravet den viktigaste parametern, inte minst för att detta har betydelse för möjligheten att upptäckta fotgängare. För att ett krav i regelverket ska vara meningsfullt är det viktigt att det är möjligt att kontrollera om kravet är uppfyllt. Emellertid är luminansmätningar komplicerade och känsliga för störningar från omgivande ljuskällor.

Syftet med denna studie har varit att utveckla en prototyp till ett instrument som möjliggör snabba mobila mätningar av vägytans luminans utan risk för störningar från annan trafik.

Genomförda tester med instrumentet har visat att mätning av vägyteluminans på längre vägsträckor kan utföras, utan ljusstörningar från annan trafik. Mätningarna är dessutom förhållandevis snabba och kräver ett minimum av manuell databearbetning. Att mätsystemet dessutom har god noggrannhet gör att det lämpar sig för tillståndsmätningar av vägbelysning.

Abstract [en]

For most types of road equipment there are regulations that set the performance requirements. For example, a road marking must have a minimum retroreflectivity for it to have sufficient visibility. Regarding road lighting there are multiple performance requirements in the Swedish Transport Administration's requirements for road and street design (VGU), including requirements for allowed glare, demands on shielding, illuminance and road surface luminance. On most roads and streets, the luminance requirement is the most important parameter, not least because this is important for the possibility of detecting pedestrians.

For a requirement in the regulations to be meaningful, it is important that it is possible to check if the requirements are met. However, luminance measurements are complicated and susceptible to interference from ambient light sources.

The purpose of this study was to develop a prototype of an instrument which enables fast mobile measurements of road surface luminance without the risk of interference from other traffic.

Completed tests with the instrument have shown that the measurement of road surface luminance on longer sections can be performed, without light interference from other traffic. The measurements are also relatively rapid and requires a minimum of manual data processing. The measurement system additionally has good accuracy which makes it suitable for condition assessment of road lighting.

Place, publisher, year, edition, pages
Linköping: Statens väg- och transportforskningsinstitut, 2017. p. 39
Series
VTI rapport, ISSN 0347-6030 ; 920
Identifiers
urn:nbn:se:vti:diva-11560 (URN)
Available from: 2017-02-08 Created: 2017-02-08 Last updated: 2017-02-08Bibliographically approved
Lahti, E., Genell, A., Anund, A. & Fors, C. (2017). SleepNoise. Linköping: ViP Driving Simulation Centre
Open this publication in new window or tab >>SleepNoise
2017 (English)Report (Other academic)
Abstract [en]

It is well known that sleepiness is an important contributor to crashes. The drivers are influenced by circadian low, hours slept or being awake. There is also reason to believe that variations in interior road noise may be a contributing factor. Up to now the road noise models in simulators are not very mature and not validated.

The aim of the technical part of the SleepNoise project was to develop the road noise model for the ViP simulation infrastructure, including individual vehicle types driving on individual road types. The goal was a sound model, close enough to the original real world setting as to be approved by vehicle noise experts. The resulting modelled interior sound spectrum should not deviate more than a few decibels from the corresponding recorded sound.

Place, publisher, year, edition, pages
Linköping: ViP Driving Simulation Centre, 2017. p. 33
Series
ViP publication: ViP - Virtual Prototyping and Assessment by Simulation ; 2016-3
Identifiers
urn:nbn:se:vti:diva-11648 (URN)
Note

På omslaget: Sleep Noise

Available from: 2017-02-24 Created: 2017-02-24 Last updated: 2017-03-10Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0002-2061-5817

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