New mandatory speed assistance technology is failing motorists in everyday driving, according to new research from Thatcham Research. Intelligent Speed Assist (ISA) systems, which became compulsory on all new cars sold in the UK and EU from July 2024, are passing official approval tests despite making mistakes on real roads.
Accuracy Drops Significantly in Real-World Driving
Researchers tested the systems every time a speed limit changed during a journey. The results showed a significant difference. The worst-performing vehicle achieved 91.3 per cent accuracy under the current distance-based test. But when measured at every speed limit change, its accuracy dropped to just 74.3 per cent.
Yousif Al-Ani, Principal ADAS Engineer at Thatcham Research, said: "Systems should be aligned with the defined speed limit parameters for each market. Where readings fall outside those recognised limits, they should be filtered to avoid unintended responses."
Driver Trust at Risk
Jonathan Hewett, Chief Executive of Thatcham Research, said advanced driver assistance systems have huge potential to improve road safety, but only if drivers trust them. He said: "ADAS technologies represent one of the most significant opportunities we have to improve road safety, but that opportunity is only realised if the systems work correctly and earn the confidence of the people using them."
Speaking about ISA specifically, Mr Hewett added that while the intent behind the legislation "is sound, helping drivers stay within speed limits saves lives," the reality can be different. "A system that misreads limits, intervenes unexpectedly or presents drivers with speed data that bears no relation to the road they are on does not assist them, it frustrates and distracts them, and they turn it off," he said.
Call for Stricter Regulatory Standards
Mr Hewett went on to share: "The automotive industry has the capability to deliver ISA that is accurate, consistent and genuinely useful. What is needed now is a regulatory standard that demands exactly that."
The findings highlight a gap between laboratory testing and real-world performance, raising questions about the effectiveness of current approval processes. Drivers may be left with systems that do not function reliably, potentially undermining the safety benefits intended by the regulation.
