To make ISA work, it is important to have a speed limit database or speed map. Within the following pages, some of the European and national initiatives are described, to discuss this issue and to make the construction of a European speed limit database possible.
Why a speed limit database?
In accordance with the White Paper “European Transport Policy for 2010: A Time to Decide” adopted by the European Commission in September 2001, one of the actions for achieving this objective is the promotion of new technologies to improve road safety: “Finally, as the volume of traffic increases, better vehicle-speed management is an essential aspect of safety that will also help tackle congestion. The most promising prospects here are offered by new technologies that can determine optimum speed at any moment with reference to traffic conditions, road features and external conditions (such as weather) and pass the information on to drivers by way of information display boards or on-board communication systems. Roads and vehicles throughout the Union need to be equipped with these new technologies as soon as possible, and information systems made accessible to everyone.”
As described above, an in-vehicle speed information and warning system is an application for highways, roads, towns, cities, housing areas or other sensitive environments in which traffic calming is currently a common method of speed restriction. In a first version, it would be possible for speed adaption systems to be used for all roads with general (implicit) speed limits and specific (explicit) speed limits. The system can be considered as one of the most promising examples of how the introduction of advanced technologies into road transport can improve safety and mobility across Europe.
A multitude of efforts in this field have been and are currently being carried out at national levels in different European countries.
based on documents of speedalert project