Emergency driving entails challenges, one being the interaction with other road users. Drivers’ attitudes towards Emergency vehicles (EVs) may affect their willingness to move over. Previous research has suggested that attitudes towards the different emergency response organizations may differ, but no previous research has compared the driver behavior aspects associated with the two organizations. The purpose of the present study was to examine drivers’ attitudes and driving behavior around approaching ambulances and police vehicles. A total of 110 drivers participated in a driving simulator study where they were approached by emergency vehicles three times. After the drive, they were asked about their typical driving behavior and attitudes towards ambulance and police. No difference in driving behavior when interacting with either an ambulance or police vehicle was seen in the simulator data. There was a difference in expressed attitude towards the organizations. Drivers reported that they felt a higher level of stress, and were more aware of their driving when approached by a police vehicle compared to when approached by an ambulance. The participants stated that it is important to move over regardless of EV type.  

Effects of rear-light usage by daylight were examined. A field experiment measured passing vehicles’ lateral distance to a stationary car, as an effect of rear-light status. A questionnaire survey measured car drivers’ perceptions regarding safety and visibility depending on rear-light usage, and their experiences, preferences, and beliefs about own usage of rear lights in daylight. An observational study measured percentages of cars with lit and unlit rear lights, respectively, in sunshine during summer. Results show that rear lights give greater lateral distance when being passed by. A car with lit rear lights is interpreted as more likely to start driving. Lit rear lights are preferred and estimated to give better visibility and traffic safety. Only a small proportion of drivers know that they drive with unlit rear lights in daylight, whilst the majority actually drive with unlit rear lights. Conclusion: lit rear lights in daylight improves traffic safety. It is therefore recommended that rear lights with sufficient brightness to be seen even in sunshine should be legally required.

Objective

This study explores the order effects in false alarms and the effect of warning modality when drivers receive an Emergency Vehicle Approaching (EVA) alert.

Background

EVA alerts have the potential to decrease delays for emergency vehicles. However, false alarms and suboptimal warning designs can decrease warning effectiveness. Aligned with previous research, drivers should benefit from receiving an alert that is not visual.

Method

A driving simulator study with 80 participants was conducted. During a 30-minute drive, the participants received three EVA alerts, one of which was false. One group received a false alert first, followed by a true alert. The other group had the opposite order. Both groups received another true alert before the experiment ended. Half of the drivers received auditory warnings, and the other half visual warnings.

Results

Drivers who received auditory warnings moved over more quickly compared to drivers who received visual alerts. There was an order effect of false warnings, suggesting that drivers who had received a false warning before they received a true warning were slower at moving over, compared to drivers who received a true warning in their first interaction. However, when the drivers received one true and one false warning each, there was no order effect in the third interaction.

Conclusion

Both alert modality and false warning effects are important when implementing EVA alerts.

Application

This research should be used to understand the order effect of false warnings on in-car warnings. When designing in-car warnings, auditory warnings may be more effective.

Projektet är en förstudie där vi studerat om teknik och kunskap från forskning inom vägtransport och intelligenta transportsystem (ITS) skulle vara möjlig att använda för att minska risken för rullbaneintrång orsakade av markfordon. Rullbaneintrång innebär att flygplan, markfordon eller personer utan tillstånd befinner sig på rullbanan (landningsbanan i vardagligt tal) eller dess skyddade närområde. Bakgrunden är att problematiken med rullbaneintrång fortsätter att vara i princip oförändrad över tid trots stora satsningar på att minska sannolikheten för att det inträffar. Många av de lösningar som har tagits fram är stora, relativt dyra systemlösningar, ofta integrerade med flygtrafikledningssystem, vilket innebär långa implementeringstider och mycket höga kostnader, vilket är ett problem för små flygplatser. 

Förstudien genomfördes i form av två litteraturöversikter för att kartlägga vad som har gjorts forskningsmässigt med avseende på rullbaneintrång med markfordonskoppling respektive forskning inom vägtrafik och ITS. Litteraturöversikterna baserade sig på strukturerade sökningar i Scopus och kompletterades med friare sökningar för att täcka området så bra som möjligt. Resultaten kategoriserades tematiskt och slutligen jämfördes de identifierade temana från de två olika områdena för att identifiera potential för användning av teknik och kunskap från vägtrafiksidan inom förhindrande av markfordonsrelaterade rullbaneintrång. Som en kompletterande aktivitet genomfördes ett mindre antal (tre) semistrukturerade intervjuer i samtalsform med fältarbetare vid tre olika svenska flygplatser. 

Av de identifierade temana från forskningen relaterad till ITS bedömdes sex stycken som intressanta att titta vidare på för möjliga tillämpningar för fordonstrafik på flygplats: cybersäkerhet, e-HMI, fordons/infrastrukturdetektering, intelligenta trafikljuslösningar samt VANET (Vehicular Ad Hoc Network). Givet de olika tematiska områdena identifierade på flygsidan och också från intervjuerna så är enkla sätt att få positionering av fordon tillgänglig för alla intressenter en viktig del. Utvecklingen mot högt automatiserade (förarlösa) fordon skapar också andra behov än idag där vi ser att teknik och kunskap från utvecklingen på vägsidan skulle kunna vara mycket intressanta, inte minst i kombination med infrastruktur. I det sammanhanget blir också cybersäkerhetsfrågan mycket viktig då sensordata kommer att samlas in och distribueras inom ett känsligt område, i allmänhet skyddsobjekt. Detta kan vara viktigt i princip oaktat andra tillämpningar då moderna fordon i mycket hög utsträckning innehåller sensorer och uppkopplad teknik. Externa gränssnitt (e-HMI) ser vi också som en fråga starkt kopplad till automatisering av fordon i en blandad miljö.  

The project is a pre-study in which we have investigated whether technology and knowledge from research in road transport and intelligent transport systems (ITS) could be used to reduce the risk of runway incursions (aircraft, ground vehicles, or persons on the runway who should not be there) at airports caused by ground vehicles. The background is that the issue of runway incursions has remained a major safety concern over time despite major efforts to reduce the likelihood of their occurrence. Many of the solutions that have been developed are large, relatively expensive system solutions, often integrated with air traffic management systems, which results in long implementation times and very high costs, something that is problematic for small airports. 

The pre-study was conducted in the form of two literature reviews based on structured database searches to map what has been done in research regarding runway incursions involving ground vehicles, and research within road traffic and ITS. The literature reviews were supplemented with more open-ended searches to cover the field as thoroughly as possible. The results were then categorized thematically, and finally, the identified themes from the two different domains were compared to identify the potential for applying technology and knowledge from the road traffic domain to the prevention of ground-vehiclerelated runway incursions. As a complementary activity, a small number (three) of semi-structured interviews in conversational form were conducted with field personnel at three different Swedish airports. 

Among the themes identified from ITS-related research, six were considered particularly interesting for further exploration in terms of possible applications to vehicle traffic at airports: automation, cybersecurity, e-HMI, vehicle/infrastructure detection, intelligent traffic light solutions, and VANET (Vehicular Ad Hoc Network). Given the thematic areas identified on the aviation side, as well as from the interviews, simple ways of making vehicle positioning available to all stakeholders are an important component. The development toward highly automated (driverless) vehicles also creates different needs compared to today, where we see that technology and knowledge from developments in the road sector could be highly relevant, not least in combination with infrastructure. In this context, cybersecurity becomes critically important, as sensor data will be collected and distributed within a sensitive area, generally designated as a protected site. This aspect may be important regardless of other applications, as modern vehicles increasingly contain sensors and connected technologies. External interfaces (e-HMI) are also seen as closely linked to the automation of vehicles in a mixed environment.

This study investigates drivers’ eye gaze behavior in response to Emergency Vehicle Approaching (EVA) warnings. EVA warnings, delivered through in-car alerts, provide advance notice of approaching EVs, enabling drivers to move over in time. Previous research indicates that EVA warnings influence driver behavior positively, promoting safer interactions. This study expands further by exploring the role of system introduction to make drivers benefit from EVA warnings. 

A simulator experiment with 73 participants was conducted. Before driving, half of the participants were introduced to the EVA system. The participants were driving on a highway and were overtaken by EVs twice during a 20-minute drive. During the drive, half of participants received EVA warnings. Gaze distribution was analyzed in three areas of interest (Forward, Mirrors, Dashboards). Analysis of driving simulator data did not reveal any differences in driving behaviors. However, the analysis of drivers’ gaze distribution suggests that EVA warnings contribute to increased mirror usage, indicating early scanning for approaching EVs. Furthermore, drivers who were introduced to the EVA system before driving but never received an EVA warning in the simulator looked through the front windshield less than drivers who were introduced and received an EVA warning. 

This study contributes to understanding the driver gaze behavior when receiving an in-car warning for emergency vehicles and supports previous findings regarding EVA warnings positive impact of driver behavior.

När man som bilist ser ett blåljusfordon i trafiken är det inte alltid helt enkelt att tolka situationen och veta hur man förväntas bete sig, och kunskapen hos bilister om betydelsen av de olika ljussignaler som utryckningsfordon använder (t.ex. fast blått sken, blinkande blåljus eller ett blinkande blått-rött ljus) är varierande. Bilisters osäkerhet och stress när de möter blåljusfordon kan leda till en ökad risk för trafikolyckor. Det är därför viktigt att undersöka hur förare av utryckningsfordon kan kommunicera sina intentioner till omgivande trafikanter.

I andra länder, exempelvis Tyskland och Irland, finns möjlighet att kombinera ljussignalering med textskyltar, vilket skulle kunna vara ett bra komplement till ljussignaler. I Sverige har den typen av textskyltar tidigare använts i begränsad utsträckning av Tullverket, men det är numera inte tillåtet enligt Trafikförordningen. Det finns dock anledning att tro att det skulle kunna underlätta i kommunikationen mellan blåljusfordon och övriga bilister.

Emergency vehicle lightings (EVL) mitigate the risk of collision and make drivers move over. The present paper explored how new alternative EVL designs can improve driver behavior in different emergency vehicle interaction scenarios. From workshops with 14 emergency responders, three scenarios (Emergency driving, Police pull-over, Emergency vehicle alongside the road) and 19 EVL blink patterns were chosen. These alternative EVLs were presented in an online survey with 2627 Swedish respondents. Alternative EVL affected reported driving behavior. Drivers reported being most certain of what is expected from them in the emergency-driving scenario. It is important to ensure that the EVL is easy to interpret in more unfamiliar emergency-vehicle interactions such as police pull-over. Only a third of drivers had seen the pull-over EVL currently used in Sweden. The current pull-over EVL in combination with a stop sign increased the chance of drivers reporting that they would pull over. 

A novel interface to provide robust, intuitive, and timely alerts to road users to move over for emergency vehicles (EVs) was tested in a seven-minute driving-simulator experiment. The interface, Augmented Emergency Lighting (AEL), mimics emergency lighting on emergency vehicles (i.e., flashing blue light), by using the cars’ interior lighting. AEL was initiated 30 seconds before an EV caught up and increased its brightness proportionally to the distance to the EV. The AEL alert was after 16 seconds accompanied by an Emergency Vehicle Approaching (EVA) alert, presented as a voice command and a text message on the dashboard. Comparisons were made between AEL+EVA alerts, EVA-only alerts, and no alerts, between groups (N = 61). Both AEL+EVA alerts and AEL-only alerts were highly successful in getting drivers to move over by slowing down and pulling off to the side as compared to when there were no alerts, but no significant difference between AEL+EVA and EVA-only was found. Questionnaire responses showed that AEL+EVA alerts were generally appreciated and that their timing was good. Further studies on learning effects and usability are discussed.

The purpose of the EVA pilot is to provide drivers with quick and accurate information and warnings about some of the possible hazardous events on the roads. This, in turn, can help prevent incidents and accidents, as well as reduce congestion. The EVA service is planned to cover Swedish highways and national roads and the pilot is aiming for deployment after the NordicWay 3 project. Furthermore, driving simulators will be used to gain a greater understanding of driver behavior when receiving EVA or Accident Zone Warnings. The pilot focuses on scenarios where the positive effects on traffic safety and emergency response times of reaching out with those warning messages are likely to be high. The established data flow infrastructure and software components from NordicWay 2 will be used.

Driving an emergency vehicle can be difficult. The driver of the emergency vehicle must navigate, communicate with emergency services, often drive at high speeds, and take surrounding traffic into account. Civilian drivers are required by law to give way to emergency vehicles with lights and sirens activated. Despite this, they sometimes fail to move over. One reason is not noticing the emergency vehicle in time.   

This dissertation aims to understand how technology can support civilian drivers in their interactions with emergency vehicles. One form of technology used to make drivers move over is emergency vehicle lighting. The results of this dissertation show that alternative designs of emergency vehicle lighting can affect driver behavior and that the current designs are not always suited to promote the most desirable driver behavior.   

Another technological approach to supporting drivers in their interactions with emergency vehicles is the use of Cooperative Intelligent Transport Systems (C-ITS). One C-ITS service is the Emergency Vehicle Approaching (EVA) warning. An EVA warning is an early in-car warning sent out to the driver before being overtaken by an emergency vehicle, providing more time to move over. Three driving simulator studies with EVA warnings were conducted in this dissertation. The results indicate that EVA warnings make drivers move over more quickly and thereby decrease delay time for emergency vehicles. Furthermore, there is a learning effect when receiving multiple EVA warnings, implying that drivers move over more quickly once they are familiar with the system. One of the simulator studies used eye tracking and showed that EVA warnings make drivers scan mirrors earlier, compared to when not receiving an EVA warning.   

Att framföra ett utryckningsfordon är utmanande. Utryckningsföraren förväntas navigera, kommunicera med larmcentralen, framföra utryckningsfordonet i inte sällan höga hastigheter och samtidigt ta hänsyn till omgivande trafik. Bilister är enligt lag tvungna att lämna fri väg för utryckningsfordon med blåljus och sirener. Trots det misslyckas ibland förare med att lämna fri väg. En anledning är att de inte hinner uppfatta utryckningsfordonet i tid.

Syftet med denna avhandling är att förstå hur teknik kan stödja förare vid interaktioner med utryckningsfordon. En form av teknik som används för att få förare att lämna fri väg är blåljus. Resultaten av denna avhandling visar att alternativa designlösningar för blåljus kan påverka förarnas beteende och att de nu-varande utformningarna inte alltid är optimala för att främja det mest önskvärda förarbeteendet.   

En annan metod för att stötta förare i deras interaktion med utryckningsfordon är uppkopplad fordonsteknik, så kallat Cooperative Intelligent Transport Systems (C-ITS). En typ av C-ITS-tjänst är Emergency Vehicle Approaching (EVA)-varningar. En EVA-varning är en tidig varning som skickas ut till bilisten innan utryckningsfordonet kör ikapp, vilket ger föraren mer tid att lämna fri väg. Tre förarsimulatorstudier med EVA-varningar genomfördes inom ramen för avhandlingen. Resultaten visar på att EVA-varningar kan få förare att lämna fri väg snabbare och därmed minska förseningar för utryckningsfordon. Dessutom finns det en inlärningseffekt med EVA varningar som innebär att förare lämnar fri väg snabbare när de är bekanta med EVA systemet. I en av simulatorstudierna användes ögonrörelsemätning som visade att EVA-varningar får förare att skanna av speglarna i bilen tidigare, jämfört med när de inte får någon EVA-varning.