ISA system in the 2015 Ford Galaxy

EU Member States take an axe to digital speed limit map data

  • June 5, 2023

Digital maps of speed limit information are critical to safety systems such as Intelligent Speed Assistance and for automated vehicles.  The information needs to be updated regularly as speed limits change.  But EU Member States are attempting to delete proposed requirements to update changes to speed limits from the majority of European roads in upcoming negotiations over the EU Intelligent Transport Systems directive.

Mandatory updates to digital maps of speed limit and other traffic information such as bridge weight limits were first announced in a directive proposal published by the European Commission in December 2021. The Commission sensibly proposed that all roads should be covered. 

But in a Member State negotiating document seen by ETSC ahead of a key meeting on 8 June to discuss the final version of the rules, countries are calling for the requirements to only apply to motorways, some other main roads, and the central areas of less than 100 cities (known as ‘urban nodes’).  

Limiting the coverage so drastically would severely reduce the effectiveness and safety potential of digital speed limit maps.  Motorway speed limits also tend not to vary much, whereas national road speed limits often change as roads pass through town centres and rural areas.  Most urban and rural roads, where the vast majority of collisions occur, will not be covered if the changes go through.   

Since July 2022, all new types of car launched in the EU must be fitted with Intelligent Speed Assistance (ISA) technology, to help drivers stick to speed limits. The most basic systems use a windscreen-based camera to read speed signs, but these do not pick up on speed limit changes when signs are missing or when the speed limit is conditional on the type of vehicle driven.  Camera-only systems are also problematic when the speed limit is not signed but implied by the fact that the vehicle is traveling on a certain type of road.  

Digital maps, linked to GPS information, are essential in these situations and are used as a critical backup to cameras in ISA systems in many new vehicles.  Assisted driving systems and fully-automated vehicles also depend on accurate digital maps of speed limits combined with sign-recognition systems. 

Graziella Jost, a specialist in vehicle safety regulation at the European Transport Safety Council said: 

“EU Member States want to take an axe to digital maps of speed limit information.  This will weaken the potential of Intelligent Speed Assistance technology, annoy drivers, and limit road safety benefits.  We urge Member States to rethink this short-sighted approach, and support investments in digital technology that can save lives.”