Ljudvarningar vid vägarbetsplatser för att uppnå sänkta hastigheter: Kartläggning och praktisk utvärdering

Susanne Gustafsson
Annika Jägerbrand

A project has been carried out to find methods that effectively decrease drivers’ speeds at road work sites through real-time audio warnings. The project consisted of two parts. First, a survey of existing studies took place. The results show that the characteristics of a successful audio alert are female voice, direct and informative messages, an interaction between semantics and acoustics, successively increased intensity, and the dimming of secondary audio distractions. Based on the results of the survey, a practical evaluation of the potential use of audio warnings at road work sites was carried out in a VTI driver simulator. Twenty-two car drivers drove 25 kilometer on a motorway where two road works were placed on the hard shoulder. Half of the subjects were given an audio warning before the first road work and the other half prior to the second roadwork. The audio warning consisted of a sound similar to that of a GPS warning signal, followed by a female voice saying "Warning! Road work within 500 meters. Adjust the speed!". The message was sent via the car's internal speaker system. The speed reducing effect is significant and the average decrease is estimated to be 9–17 km/h greater with audio warning than without. Furthermore, there was still a small effect (0.5–3.3 km h) left of the audio alert after the road works. More results of the simulation tests are presented along with the drivers’ subjective opinions of such systems.



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.



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.


Steps need to be taken to increase traffic safety of automated cars

Several steps are necessary to ensure that automated and connected cars will lead to increased traffic safety – everything from ensuring that technology takes vulnerable road users into account, to new forms of driver training. This has emerged in a position...


FALCON examines challenges in the transport sector

VTI is one of several important partners in the major FALCON project*, whose purpose is to create knowledge and insight regarding the transport sector. In an initial subproject, VTI has produced a manual on transport, logistics and multimodality.


VTI joined research cooperation in China

In December 2017 VTI became a member of China-Sweden Research Centre for Traffic Safety (CTS).


Swedish German research collaboration on Electric Road Systems

The project “Swedish-German research collaboration on Electric Road Systems” (CollERS) has now officially started. The goal of the project is to increase the common knowledge around Electric Road Systems by cooperation between Germany and Sweden and to...


Electric Road Systems Conference 2018

After a successful first conference in June 2017, the Swedish research and innovation platform for electric roads is arranging the second dedicated International Conference on Electric Road Systems (ERS) June 13th and 14th 2018.