This paper describes an analysis of microscopic traffic behaviour when entering a motorway. The study is part of the DRIVE II project ROSES, in which an integrated infrastructure based and on-board road and weather monitoring system is developed and tested.

A simulation model has been built, which incorporates the characteristics of vehicle performance and the driver control. For the subsequent phases of the entering procedure, a driver behaviour model has been designed.

One specific road lay-out is investigated, while traffic situation and road friction are varied in a number of scenarios. Simulation results show that in slippery conditions a reduction of the mainstream traffic speed is required in order to maintain a proper safety level.

The results of this study can be used in advanced traffic control and in-vehicle safety systems.