Crash prevention technologies that detect people who are walking – like automatic emergency braking systems that warn drivers when they’re at risk of hitting a person and apply the brakes to avoid or lessen the impact – are successful in preventing collisions, but only during the day or on well-lit roads. The systems do not make a difference in the dark.
Those are the main findings of a new study based on real-world crash data released on Thursday by the Insurance Institute for Highway Safety, a nonprofit financed by the insurance industry, that assessed the impact of pedestrian automatic emergency braking (AEB) on its ability to reduce the number of motor vehicle crashes with people.
Crash avoidance technology for walkers is critical, the safety group noted, as pedestrian crash deaths have risen 51% since 2009.
“This is the first real-world study of pedestrian AEB to cover a broad range of manufacturers, and it proves the technology is eliminating crashes,” Jessica Cicchino, vice president of research at the Insurance Institute and the study’s author, said in a statement. “Unfortunately, it also shows these systems are much less effective in the dark, where three-quarters of fatal pedestrian crashes happen.”
For the study, researchers looked at nearly 1,500 police-reported crashes involving a range of 2017-2020 model-year vehicles from different manufacturers. Pedestrian crash rates for identical vehicles with and without pedestrian AEB were compared. Crash severity, light conditions, speed limit, and whether the vehicles were turning or not were also assessed.
In all light conditions, the technology cut the pedestrian crash rates of all levels of severity by 27 % and the rate of pedestrian crashes with injuries by about 30%. But when researchers looked at crashes that occurred at night on roads without street lights, there was no difference in crash risk for vehicles equipped with and without pedestrian automatic emergency braking (AEB).
In addition to the analysis based on real-world crash data, the Insurance Institute undertook some nighttime testing of vehicles with pedestrian AEB systems to gauge their effectiveness.
For the tests, which are still in the development stage, eight small SUVs made by eight different manufacturers were evaluated in full darkness on a covered track. Each vehicle was tested twice — first with their high-beam headlights on and then their low beams.
The results of the preliminary track tests were consistent with those from the examination of real world data, the insurance institute said, and will be used as a foundation for a new ratings system.
In areas that were not lit, there was no difference in the odds of a nighttime pedestrian crash for vehicles with and without the crash avoidance technology, the safety group said. And slower speeds reduced the odds of a pedestrian crash, but speeds of 50 mph or higher and when a vehicle was turning resulted in no reduction at all.
However, on a positive note, there is some indication that some manufacturers are already improving the nighttime performance of their pedestrian AEB systems, David Aylor, manager of active safety testing at the Insurance Institute said in a statement.
The Insurance Institute plans to publish the first nighttime pedestrian crash prevention ratings later this year to encourage manufacturers to improve nighttime performance.
