What characterizes a free vehicle in an urban area?

Publisher's full text

The concept "free vehicle" is used widely in the transportation research literature, but as yet there is no common standard for a definition. In this article a standard is provided that is based on the assumption that a vehicle can be considered free, when its speed is not influenced by the speed of the vehicle traveling ahead. In order to determine empirically a threshold for free vehicles in urban areas, speed, distance headway, and time headway data of more than 100 000 vehicles were analyzed. Analyses showed that the speeds of two vehicles are linearly dependent on time headway for headways up to 6 s. It is important to distinguish between this value and the drivers' preferred headway, which is in the region of 2 s

MEET US


25-27
Aug

ICTTP 2020

ICTTP, International Conference on Traffic and Transport Psychology, is held in Gothenburg, Sweden.

LATEST NEWS


2018-11-19

Report regarding government commission on the costs of traffic to society has been submitted

Since 2013, the Swedish National Road and Transport Research Institute (VTI) has had several government commissions to produce documentation on the costs to society caused by traffic. On 1 November 2018, the agency reported its latest commission, Samkost 3....


2018-10-29

International standardisation efforts have many advantages

VTI participates in several international standardisation committees. The work is important because it helps to ensure that standards can be adapted to Swedish conditions and it also provides access to valuable contacts and networks.


2018-10-24

China wants to work with the best

Through the CTS cooperation, VTI is gaining valuable research contacts with China. The country is facing major challenges in the field of road safety but also has enormous potential.


2018-10-23

VTI participated in conference on electric roads

Systems with electrified roads are a relatively new concept and many projects have been launched in recent years. To stimulate the transfer of knowledge and collaboration, the Research and Innovation Platform for Electric Roads arranged its second...


2018-10-18

ADAS&ME is tackling the interaction between people and technology

ADAS&ME is a major EU project focused on automation, the human condition and the human environment. The budget is EUR 9.6 million and VTI is the coordinator.


2018-10-05

Users contribute to the development of train simulators

Apart from advanced driving simulators, VTI has developed several variations of train simulators which are used for training, education and research. In recent years, interest has increased drastically among major actors in the railway sector, and VTI has...