The rollout of speed limiter technology on UK roads has been dealt a major blow after Britain's largest vehicle safety body revealed that it fails to accurately identify changes in legal speed limits up to one in four times. The Intelligent Speed Assistance (ISA) systems, set to become compulsory from July 2024, are supposed to alert drivers when they exceed the limit and even reduce engine power.
However, extensive testing on UK roads by the vehicle safety body has highlighted serious inaccuracies within these ISA systems. In some cases, the technology misinterprets speed limits, displaying an incorrect limit or failing to recognise a change in limit altogether. For example, it might continue to show a 30 mph limit even after entering a 40 mph zone.
The discrepancies were observed across various road types and conditions, suggesting a systemic issue rather than isolated incidents. The technology typically relies on camera recognition of speed signs and GPS data linked to digital maps. Experts say environmental factors such as poor weather or outdated map data could contribute to these inaccuracies.
With the potential for drivers to become confused or frustrated by incorrect guidance, there are concerns that ISA systems could lead to unintended speeding offences. While their intention is to enhance road safety and reduce accidents caused by speeding, the current level of inaccuracy raises significant questions about their reliability and effectiveness on British roads.
The vehicle safety body's findings will likely prompt calls for manufacturers and regulatory bodies to address these flaws before the full implementation deadline. With a July 2024 target for all new cars sold in the UK to be fitted with ISA systems, there is growing pressure to ensure they are robust and reliable.