Pedestrian detection technology could be less accurate with the use of reflective clothing, according to IIHS.

A new study conducted by the Insurance Institute for Highway Safety (IIHS) has shed light on potential issues with the performance of automatic emergency braking (AEB) systems when encountering pedestrians wearing reflective clothing.

The study, published this month, tested the AEB systems in 2023 model year Honda CR-V, Mazda CX-5, and Subaru Forester vehicles. The tests were conducted at speeds of 25 miles per hour with varying amounts of lighting in the crosswalk, according to the Federal Highway Administration's Visibility Research Program.

Each vehicle tested was equipped with automatic emergency braking. The dummy was moved across a street within a crosswalk to mimic a pedestrian in the tests. The dummy was dressed in different outfits, including black attire, a black outfit with reflective strips, a reflective jacket with black pants, and a white outfit.

In normal conditions, the AEB reduced pedestrian crashes by 27%, according to IIHS research. However, the study found that reflective strips on clothing can hinder the performance of some vehicles' AEB systems. Both the Mazda CX-5 and the Honda CR-V did not slow at all when the dummy was wearing reflective strips. The Subaru Forester performed well in tests, avoiding a collision in nearly every trial, but did not fully stop when the dummy was wearing reflective strips, reducing speed by 82%.

David Kidd, a senior research scientist at IIHS and co-author of the study, stated that the reflective strips likely "confounded" the sensors of the tested cars. The IIHS President, David Harkey, stated that it's untenable that safety clothing may make pedestrians harder for crash avoidance technology to recognize.

The results of the study suggest that some automakers need to tweak their pedestrian automatic emergency braking systems. According to the IIHS study report, Ford, Toyota, and Volkswagen need to adjust their pedestrian automatic emergency braking systems to reduce the impact of reflective stripes on system effectiveness. The study did not provide information about which specific automakers' AEB systems were affected by reflective strips, other than the Honda CR-V and Mazda CX-5.

It's important to note that the study did not mention any other potential factors affecting the performance of AEB systems in varied lighting conditions. The Mazda CX-5 slowed less when faced with the reflective jacket than it did when the dummy was wearing all black. This indicates that the AEB systems may be more effective in brighter conditions, but further research is needed to confirm this.

In conclusion, the IIHS study highlights a potential issue with the performance of AEB systems when encountering pedestrians wearing reflective clothing. It's hoped that this research will prompt automakers to address this issue and improve the safety of their vehicles for all road users.