Bicyclists‘ speed adaptation strategies when conducting self-paced vs. system-paced smartphone tasks in traffic

Publisher's full text
Lisa Palmqvist
Emeli Adell

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



Cost Benefit Analysis (CBA) workshop in Stockholm

An open seminar and workshop in Stockholm will be held on 25-26 April 2018. The workshop deals with the use of CBA as a basis for decision-making in the public sector. The workshop is organized by, among others, Professor Jan-Eric Nilsson, VTI.

The 6st Humanist Conference

The 6th HUMANIST Conference will take place 13-14 June 2018 in the Hague, The Netherlands. The scope of the conference covers a wide range of topics on Human Factors in Transport. Tania Willstrand and Alexander Eriksson will present their research results.



VTI will develop simulators for ambulance staff

VTI has initiated a pilot study for paramedics with the Centre for Teaching & Research in Disaster Medicine and Traumatology and Linköping University. The aim is to give ambulance staff the opportunity to practice critical medical tasks in a moving vehicle in...


Unique electrified road opens in Sweden

The world’s first electrified road recharging the batteries of cars and trucks while driving opened in Sweden. The Swedish Minister for Infrastructure, Tomas Eneroth, was at the formal inauguration of the electrified road on April 11, 2018. VTI is one of 22...


Swedish road safety spreads internationally

Sweden is a leading country in terms of road safety, and the research conducted by the Swedish National Road and Transport Research Institute (VTI) has contributed to increased safety. VTI’s remit includes disseminating research results and keeping up to date...


A greater understanding of cyclists' behaviour

Cyclists are often accused of not following traffic rules and being hooligans on the road. New research shows that there is no support for this perception. "Our observations reveal no such general anarchy" says Sonja Forward, researcher at VTI.


New technology for road surface measurement tested

VTI has tested a new scanning-laser technology for road surface measurement. The tests show the new technology for comprehensive transverse-profile measurement provides dependable values in measuring transverse profile and rut depth.


Ulf Sandberg has been presented with the TTI Lifetime Achievement Award 2018

VTI’s Senior Research Leader Ulf Sandberg has been presented with the TTI Lifetime Achievement Award 2018 for his work on research into tyres and road surface.