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Ahlström, C., Wachtmeister, J., Nyman, M., Nordenström, A. & Kircher, K. (2019). Using smartphone logging to gain insight about phone use in traffic. Cognition, Technology & Work
Open this publication in new window or tab >>Using smartphone logging to gain insight about phone use in traffic
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2019 (English)In: Cognition, Technology & Work, ISSN 1435-5558, E-ISSN 1435-5566Article in journal (Refereed) Published
Abstract [en]

The prevalence of mobile phone usage in traffic has been studied by road-side counting, naturalistic driving data, surveillance cameras, smartphone logging, and subjective estimates via surveys. Here, we describe a custom-made smartphone logging application along with suggestions on how future such applications should be designed. The developed application logs’ start and end times of all phone interactions (mobile phone applications, incoming/outgoing phone calls and text messages, audio output, and screen activations). In addition, all movements are automatically classified into transport, cycling, walking, running, or stationary. The capabilities of the approach are demonstrated in a pilot study with 143 participants. Examples of results that can be gained from smartphone logging include prevalence in different transportation modes (here found to be 12% while driving, 4% while cycling, and 7% while walking), which apps are being used (here found to be 19% navigation, 12% talking, 12% social media, and 10% games) and on which road types (rural, urban, highway etc.). Smartphone logging was found to be an insightful complement to the other methods for assessing phone use in traffic, especially since it allows the analyses of which apps are used and where they are used, split into transportation mode and road type, all at a relatively low cost.

Place, publisher, year, edition, pages
Springer London, 2019
Keywords
Mobile phone, Use, Data acquisition, Mobile application, Transport mode
National Category
Applied Psychology
Research subject
80 Road: Traffic safety and accidents, 841 Road: Road user behaviour
Identifiers
urn:nbn:se:vti:diva-13654 (URN)10.1007/s10111-019-00547-6 (DOI)2-s2.0-85061633847 (Scopus ID)
Available from: 2019-05-17 Created: 2019-05-17 Last updated: 2019-06-27Bibliographically approved
Nygårdhs, S., Ahlström, C., Ihlström, J. & Kircher, K. (2018). Bicyclists' adaptation strategies when interacting with text messages in urban environments. Cognition, Technology & Work, 20(3), 377-388
Open this publication in new window or tab >>Bicyclists' adaptation strategies when interacting with text messages in urban environments
2018 (English)In: Cognition, Technology & Work, ISSN 1435-5558, E-ISSN 1435-5566, Vol. 20, no 3, p. 377-388Article in journal (Refereed) Published
Abstract [en]

Cyclists' use of mobile phones in traffic has typically been studied in controlled experiments. How cyclists adapt their behaviour when they are not limited to a certain set of behaviours has not been investigated to any large extent. The aims of this study are to explore how cyclists adapt when texting and listening to music in a complex urban environment, and if they compensate sufficiently to maintain safe traffic behaviour. Forty-one cyclists participated in a semi-controlled study, using their own bike and smartphone in real traffic. They were equipped with eye tracking glasses and travelled two laps completing a total of 6 km divided into six segments. For one of the laps, the cyclists were requested to listen to music. On three occasions, they received a text message to their phone, which they were supposed to handle as they normally would when cycling. Static minimum required attention measures were used to examine the influence on attention. The results show that listening to music while cycling did not affect workload, speed, SMS interaction or attention. Seven different adaptation behaviours were identified when the cyclists dealt with received text messages. One-fourth of the text messages were replied to while cycling. In general, the cyclists manage to integrate SMS interactions with their cycling behaviour. Nevertheless, there were two occasions when basic attention criteria were violated while texting, which motivate further studies.

Place, publisher, year, edition, pages
SPRINGER LONDON LTD, 2018
Keywords
Cyclist, Behaviour, Mobile phone, Use, Cycling, Attention, Mental load
National Category
Human Aspects of ICT
Research subject
80 Road: Traffic safety and accidents, 841 Road: Road user behaviour
Identifiers
urn:nbn:se:vti:diva-13185 (URN)10.1007/s10111-018-0478-y (DOI)000439906300004 ()2-s2.0-85045467252 (Scopus ID)
Available from: 2018-09-12 Created: 2018-09-12 Last updated: 2018-11-19Bibliographically approved
Kircher, K., Ihlström, J., Nygårdhs, S. & Ahlström, C. (2018). Cyclist efficiency and its dependence on infrastructure and usual speed. Transportation Research Part F: Traffic Psychology and Behaviour, 54, 148-158
Open this publication in new window or tab >>Cyclist efficiency and its dependence on infrastructure and usual speed
2018 (English)In: Transportation Research Part F: Traffic Psychology and Behaviour, ISSN 1369-8478, E-ISSN 1873-5517, Vol. 54, p. 148-158Article in journal (Refereed) Published
Abstract [en]

Bicyclists are a heterogeneous group, with varying abilities, traffic education and experience. While efficiency was identified as an important factor on utility bicycle trips, it might be traded for experienced safety, for example by choosing different pathways in a given situation, or by relinquishing one's right of way. In a semi-controlled study with 41 participants, a grouping was made according to self-reported riding speed in relation to other cyclists. The participants cycled twice along a 3 km inner-city route, passing four intersections with different priority rules. The cyclists were free to choose how to negotiate the intersections. Speed and the traffic surroundings were recorded via gps and cameras on the bike of the participant and of a following experimenter. For each cyclist, the ‘base’ speed on undisturbed segments was determined as reference. Based on this, the efficiency in different types of intersections was computed per cyclist group. It turned out that infrastructural aspects, cyclist group and the presence and behaviour of interacting traffic influenced cyclist efficiency. Faster cyclists were delayed more when the infrastructure required a stop regardless of the traffic situation, like at a red traffic light or a stop sign. The members of the so-called ‘comfort cyclists’ group were delayed the most in a roundabout with mixed traffic, where many chose to get off their bike and walk. In a society working for equality of access to the transport system, it is recommended to develop solutions that consider and accommodate the behaviours of different cyclist groups when planning bicycling infrastructure.

Place, publisher, year, edition, pages
Elsevier Ltd, 2018
Keywords
Cyclist, Behaviour, Junction, Traffic mixture, Design (overall design), Efficiencey, Journey
National Category
Infrastructure Engineering
Research subject
10 Road: Transport, society, policy and planning, 113 Road: Cycling, walking and moped transport
Identifiers
urn:nbn:se:vti:diva-12861 (URN)10.1016/j.trf.2018.02.002 (DOI)2-s2.0-85042191714 (Scopus ID)
Available from: 2018-04-05 Created: 2018-04-05 Last updated: 2018-05-21Bibliographically approved
Wallén Warner, H., Niska, A., Forward, S., Björklund, G., Eriksson, J., Kircher, K., . . . Nygårdhs, S. (2018). En modell för säker cykling. Linköping: Statens väg- och transportforskningsinstitut
Open this publication in new window or tab >>En modell för säker cykling
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2018 (Swedish)Report (Other academic)
Alternative title[en]
A model for safe cycling
Abstract [sv]

Avsikten med det tvärvetenskapliga forskningsprogrammet En stark forskningsmiljö inom området hjulburna oskyddade trafikanter är att öka kunskapen om hjulburna oskyddade trafikanter och deras speciella förutsättningar i trafikmiljön för att på sikt kunna bidra till att nå det nationella hänsynsmålet med fokus på säkerhet. Syftet med denna modellrapport är att sammanfatta resultat och föreslagna åtgärder från de övriga åtta projekten inom ramen för forskningsprogrammet, men även från tidigare forskning och andra programövergripande aktiviteter, i en modell för säker cykling. Med modell avser vi i detta fall en lista över åtgärdsförslag som i enlighet med Haddons matris, utökad med förutsättningar, är riktade mot cyklisten, cykeln och trafikmiljön. För varje åtgärdsförslag finns även angivet var i händelseförloppet från förutsättningar till krasch som åtgärden bör sättas in samt vilka aktörer vi anser är lämpade att initiera och implementera åtgärdsförslagen. För att åstadkomma säker cykling visar resultaten att man måste titta på transportsystemet i sin helhet vilket i sin tur kräver samverkan mellan olika aktörer. Slutligen behövs fortsatt forskning för att kunna optimera utformningen av de olika åtgärderna och utvärdering för att säkerställa att de haft önskad effekt.

Abstract [en]

The main aim of the multi-disciplinary scientific research programme A strong research environment in the field of non-motorised vulnerable road users is to increase our knowledge of unprotected twowheeled or non-motorised road users and their special requirements in the road traffic environment. The aim being to, in the long-term, to contribute to the Swedish national road safety goals. The objective of the Model for Safe Cycling report is to summarise the results and suggested actions from the eight projects that were conducted within the framework of the research programme; a literature study; and other programme related activities, in a conceptual model based on Haddon’s matrix. With a model, in this case, we mean that a list of suggested implementation actions, structured according to Haddon’s matrix and embellished with prerequisites directed towards the cyclist, the bicycle and the road environment. Each of the suggested actions or implementation suggestions, are organised along the chain of events from the prerequisite phase to the crash phase. Stakeholders are identified for each of the suggested actions for implementation. In summary, the results suggest one must look at the (road) transport system as a whole to provide a system for safe cycling. To be able to acquire a holistic approach, cooperation between stakeholders is necessary. Finally, more research is required to find optimal solutions and designs tailored to the actions that must also be evaluated to assure that the desired effects are reached.

Place, publisher, year, edition, pages
Linköping: Statens väg- och transportforskningsinstitut, 2018. p. 101
Series
VTI rapport, ISSN 0347-6030 ; 979
Keywords
Cycling, Cyclist, Bicycle, Safety, Accident prevention, Method, Model (not math)
National Category
Transport Systems and Logistics
Research subject
80 Road: Traffic safety and accidents; 80 Road: Traffic safety and accidents, 82 Road: Geometric design and traffic safety; 80 Road: Traffic safety and accidents, 84 Road: Road users
Identifiers
urn:nbn:se:vti:diva-13236 (URN)
Available from: 2018-09-03 Created: 2018-09-03 Last updated: 2019-06-05Bibliographically approved
Solis Marcos, I. & Kircher, K. (2018). Event-related potentials as indices of mental workload while using an in-vehicle information system. Cognition, Technology & Work, 1-13
Open this publication in new window or tab >>Event-related potentials as indices of mental workload while using an in-vehicle information system
2018 (English)In: Cognition, Technology & Work, ISSN 1435-5558, E-ISSN 1435-5566, p. 1-13Article in journal (Refereed) Published
Abstract [en]

New in-vehicle information systems are now being commercialized. Despite the expected benefits, some concerns exist that they may overload drivers’ capacity and decrease performance. According to the multiple resource theory, overload may occur at different stages of processing, that is, perceptual–central and/or response-related stages. Therefore, different measures may be needed to detect such specific demands. We explored the sensitivity of different mental workload measurements during the performance of an auditory task alone (single task) and in combination with a tracking task that was presented without (dual task) or, with a visual display (triple task). The demands associated with the number of concurrent tasks (single, dual and triple tasks), tracking speed (low, high, adjustable) and their interaction were analyzed. To account for different processing requirements, mental workload was assessed using subjective, behavioral (performance on the auditory task) and psychophysiological measurements (event-related potentials). 17 young adults participated in the study. The results showed that most measurements discriminated between the performances of one or more tasks, as well as between low and high speeds. However, only the subjective ratings and tracking task performance further discriminated between the dual- and triple-task conditions. Finally, ERPs (N1 and P3) were the only measure detecting increases in cognitive demands associated with higher requirements on processing speed combined with the addition of the display. Our results suggest that ERPs may provide complementary information to other traditional mental workload measures. Its applications in the evaluation and design of future systems should be investigated.

Place, publisher, year, edition, pages
Springer London, 2018
Keywords
In vehicle information, Mental load, Measurement, Driver
National Category
Production Engineering, Human Work Science and Ergonomics
Research subject
80 Road: Traffic safety and accidents, 841 Road: Road user behaviour; 90 Road: Vehicles and vehicle technology, 914 Road: ITS och vehicle technology
Identifiers
urn:nbn:se:vti:diva-13093 (URN)10.1007/s10111-018-0485-z (DOI)2-s2.0-85045905005 (Scopus ID)
Available from: 2018-07-25 Created: 2018-07-25 Last updated: 2018-08-13Bibliographically approved
Solis Marcos, I., Ahlström, C. & Kircher, K. (2018). Performance of an Additional Task During Level 2 Automated Driving: An On-Road Study Comparing Drivers With and Without Experience With Partial Automation. Human Factors
Open this publication in new window or tab >>Performance of an Additional Task During Level 2 Automated Driving: An On-Road Study Comparing Drivers With and Without Experience With Partial Automation
2018 (English)In: Human Factors, ISSN 0018-7208, E-ISSN 1547-8181Article in journal (Refereed) In press
Abstract [en]

Objective: To investigate the influence of prior experience with Level 2 automation on additional task performance during manual and Level 2 partially automated driving.

Background: Level 2 automation is now on the market, but its effects on driver behavior remain unclear. Based on previous studies, we could expect an increase in drivers’ engagement in secondary tasks during Level 2 automated driving, but it is yet unknown how drivers will integrate all the ongoing demands in such situations.

Method: Twenty-one drivers (12 without, 9 with Level 2 automation experience) drove on a highway manually and with Level 2 automation (exemplified by Volvo Pilot Assist generation 2; PA2) while performing an additional task. In half of the conditions, the task could be interrupted (self-paced), and in the other half, it could not (system-paced). Drivers’ visual attention, additional task performance, and other compensatory strategies were analyzed.

Results: Driving with PA2 led to decreased scores in the additional task and more visual attention to the dashboard. In the self-paced condition, all drivers looked more to the task and perceived a lower mental demand. The drivers experienced with PA2 used the system and the task more than the novice group and performed more overtakings.

Conclusions: The additional task interfered more with Level 2 automation than with manual driving. The drivers, particularly the automation novice drivers, used some compensatory strategies.

Applications: Automation designers need to consider these potential effects in the development of future automated systems.

Place, publisher, year, edition, pages
Sage Publications, 2018
Keywords
Advanced driver assistance system, Mental load, Attention, Behaviour, Driver
National Category
Production Engineering, Human Work Science and Ergonomics
Research subject
80 Road: Traffic safety and accidents, 841 Road: Road user behaviour
Identifiers
urn:nbn:se:vti:diva-13133 (URN)10.1177/0018720818773636 (DOI)2-s2.0-85047381768 (Scopus ID)
Available from: 2018-06-28 Created: 2018-06-28 Last updated: 2018-08-13Bibliographically approved
Kircher, K., Ahlström, C., Nylin, M. & Mengist, A. (2018). Tactical steering behaviour under irrevocable visual occlusion. Transportation Research Part F: Traffic Psychology and Behaviour, 55, 67-77
Open this publication in new window or tab >>Tactical steering behaviour under irrevocable visual occlusion
2018 (English)In: Transportation Research Part F: Traffic Psychology and Behaviour, ISSN 1369-8478, E-ISSN 1873-5517, Vol. 55, p. 67-77Article in journal (Refereed) Published
Abstract [en]

Objective: To investigate the extent of a driver's mental model with irrevocable visual occlusion and analysing the distance to crash.

Background: Drivers have a mental model of the immediate surroundings which allows them to predict their own as well as others' travel paths. To navigate safely through traffic, this mental model has to be updated frequently to remain valid. In between information sampling events, the mental model will become outdated over time, as the traffic system is dynamic.

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

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

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

Place, publisher, year, edition, pages
ELSEVIER SCI LTD, 2018
Keywords
Driver, Cognition, Vision, Driver information, Simulator (driving)
National Category
Infrastructure Engineering
Research subject
80 Road: Traffic safety and accidents, 841 Road: Road user behaviour
Identifiers
urn:nbn:se:vti:diva-13112 (URN)10.1016/j.trf.2018.02.035 (DOI)000432641100007 ()
Available from: 2018-09-10 Created: 2018-09-10 Last updated: 2018-11-21Bibliographically approved
Ahlström, C. & Kircher, K. (2017). A Generalized Method to Extract Visual Time-Sharing Sequences From Naturalistic Driving Data. IEEE transactions on intelligent transportation systems (Print), 18(11), 2929-2938
Open this publication in new window or tab >>A Generalized Method to Extract Visual Time-Sharing Sequences From Naturalistic Driving Data
2017 (English)In: IEEE transactions on intelligent transportation systems (Print), ISSN 1524-9050, E-ISSN 1558-0016, Vol. 18, no 11, p. 2929-2938Article in journal (Refereed) Published
Abstract [en]

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

Place, publisher, year, edition, pages
Institute of Electrical and Electronics Engineers (IEEE), 2017
Keywords
Vision, Behaviour, Method, Measurement, Data acquisition, Eye movement
National Category
Transport Systems and Logistics
Research subject
80 Road: Traffic safety and accidents, 841 Road: Road user behaviour
Identifiers
urn:nbn:se:vti:diva-12509 (URN)10.1109/TITS.2017.2658945 (DOI)000414070100004 ()2-s2.0-85016486695 (Scopus ID)
Available from: 2017-11-17 Created: 2017-11-17 Last updated: 2017-12-04Bibliographically approved
Ahlström, C. & Kircher, K. (2017). Changes in glance behaviour when using a visual eco-driving system: A field study. Applied Ergonomics, 58, 414-423
Open this publication in new window or tab >>Changes in glance behaviour when using a visual eco-driving system: A field study
2017 (English)In: Applied Ergonomics, ISSN 0003-6870, E-ISSN 1872-9126, Vol. 58, p. 414-423Article in journal (Refereed) Published
Abstract [en]

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

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

Keywords
Electronic driving aid, Environment, Driver, Attention, Test, Eye movement
National Category
Applied Psychology
Research subject
80 Road: Traffic safety and accidents, 841 Road: Road user behaviour; 90 Road: Vehicles and vehicle technology, 914 Road: ITS och vehicle technology
Identifiers
urn:nbn:se:vti:diva-10871 (URN)10.1016/j.apergo.2016.08.001 (DOI)2-s2.0-84981313642 (Scopus ID)
Available from: 2016-08-31 Created: 2016-08-31 Last updated: 2017-11-21Bibliographically approved
Liu, Z. & Kircher, K. (2017). Comparison of a time- and a speed-based traffic light assistance system. Cognition, Technology & Work, 1-11
Open this publication in new window or tab >>Comparison of a time- and a speed-based traffic light assistance system
2017 (English)In: Cognition, Technology & Work, ISSN 1435-5558, E-ISSN 1435-5566, p. 1-11Article in journal (Refereed) Published
Abstract [en]

Traffic light assistance systems (TLASs) can be infrastructure based or on-board, and in the latter case they can inform the driver about the time remaining to green, or about the recommended speed for a smooth passage at green. A speed-based and a time-based on-board system prototype was compared against each other and against a baseline without any assistance system. Using a within-subjects design, 18 participants drove in a fixed-base simulator along a suburban road with signalised intersections, where the delay to green was set to zero (allowing a passage at the current speed), “half-speed” (requiring a clear speed reduction) and “stop” (requiring a substantial speed reduction). Driving behaviour, visual attention distribution and acceptance were evaluated. Both support systems improved driving efficiency and comfort over baseline, with the time-based system achieving higher scores in general. Both systems attracted a substantial amount of visual attention in the current setting; however, single-glance durations were below 1 s, and the number of glances forward were equal in the time-based condition compared to baseline, but lower in the speed-based condition. No red or amber light violations were registered in baseline, while some occurred with any of the systems. Acceptance for both systems was high, with higher scores for the time-based prototype. Overall, an on-board TLAS with a countdown timer to green has the potential to increase efficiency and comfort without strong indications for attention disruption, but the risk for increased red/amber light violations has to be addressed. Improved system design as a way to mitigate potential issues is discussed.

Place, publisher, year, edition, pages
Springer London, 2017
Keywords
Traffic light, Driver information, Time, Speed, Recommendations, Simulator (driving), Behaviour, Attention, Acceptability
National Category
Infrastructure Engineering
Research subject
20 Road: Traffic engineering, 22 Road: Traffic control and traffic information
Identifiers
urn:nbn:se:vti:diva-12764 (URN)10.1007/s10111-017-0458-7 (DOI)000425116800007 ()2-s2.0-85039756899 (Scopus ID)
Available from: 2018-05-24 Created: 2018-05-24 Last updated: 2018-06-12Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0002-1849-9722

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