Relationship Between Speed And Lateral Position On Curves

Shauna L. Hallmark
Neal Hawkins
Omar Smadi

Lane departure crashes are a significant safety concern. The majority of lane departure crashes occur in rural areas, mostly on 2-lane roadways. A disproportionate number of these crashes occur on horizontal curves. Curve related crashes involve a number of roadway and driver causative factors. Understanding how drivers negotiate curves can assist in application of countermeasures.One aspect of curve negotiation that is not well documented is the relationship between lateral position and speed. This relationship was assessed by comparing the odds of a near lane crossing for vehicles traveling 5 or more mph over the advisory speed to those for vehicles traveling below that threshold. Data were collected using a “Z” configuration of road tubes at three rural 2-lane curves in Iowa (USA). Data were collected at various locations within those curves including the PC and center of curve. Data were compared for daytime and nighttime separately since driver behavior can vary during these time periods. When results were statistically significant, vehicles at higher speeds had greater odds of near lane crossings.



Millions for research into maritime transport and the environment

Maritime transport is a major source of emissions of harmful air pollutants and carbon dioxide. In a new project, a research team from the Swedish National Road and Transport Research Institute (VTI) and the University of Gothenburg has received SEK 6.4...


New research programme for more efficient travel

The Swedish National Road and Transport Research Institute (VTI) is playing an important role in a major new research programme to find radical solutions leading to fewer trips and more efficient travel, along with tools to enable better use of roads and...


Simulator used to practice emergency responses safely

Emergency responses of the police, ambulance, and rescue services are associated with a high risk of accidents, but practicing them in real traffic is neither safe nor permissible. A simulator-based method developed by the Swedish National Road and Transport...


Simulation of cut-in by manually driven vehicles in platooning scenarios

A study in a VTI-driving simulator has showed that a platoon will be able to handle a cut in from a manually driven car. The results of this study have recently been presented at two conferences in Japan.



The five-year anniversary of European Road Profile Users' Group (ERPUG) Forum will take place at Ramboll head quarter, Copenhagen, Denmark October 19-20, 2017.


Self-driving buses in Sweden next year?

A self-driving, fossil-free bus. This idea might become reality through a forthcoming collaborative project involving the Swedish National Road and Transport Research Institute (VTI), Linköping University and several other participants. The project group aim...