Principal Investigator: Thomas Seacrist, MBE, Children’s Hospital of Philadelphia

WHAT WAS THE PURPOSE OF THIS PROJECT?

The Strategic Highway Research Program 2 (SHRP2) is a large naturalistic driving study that recorded information from vehicles driven by 3,000 drivers over two years. SHRP2 ended in 2015 and, at that time, none of the vehicles involved in the study had automatic emergency braking (AEB). Therefore, the goal of this study was to look at the rear-end crashes in the SHRP2 database and re-create them using a mathematical simulation as if the vehicles had AEB.

WHY DID YOU FOCUS ON THIS ISSUE?

The most common crash scenario is when the case vehicle impacts the rear of another car, which is particularly troublesome for drivers at higher risk of crashing, including teens. Previous SHRP2 research found teens tend to be involved in rear-end crashes up to 10 times more often than experienced adult drivers. We wanted to see how effective AEB might have been in preventing these drivers from getting into rear-end crashes.

WHAT DID YOU FIND AND WERE ANY OF THE RESULTS SURPRISING?

We found AEB to be very effective; it would have prevented up to 79 percent, or 31 of the 39 rear-end crashes simulated in this project. Previous studies estimated that AEB would prevent up to 57 percent of the crashes and injuries but did not include the real-world data that SHRP2 provides, such as the exact speed of the vehicle, what the driver was doing at the time, and road conditions. So, our findings were a pleasant surprise. However, we did find that AEB was less effective during high-speed crashes or in bad weather.

WHAT ARE THE INDUSTRY IMPLICATIONS FOR THESE FINDINGS?

We hope automotive manufacturers will use the results to improve AEB to prevent crashes at higher speeds and in inclement weather. More importantly, we must also ensure that these vehicles with AEB get into the hands of teen drivers; this will require educational and promotional campaigns with teens and parents.

Co-Investigator

Helen Loeb, PhD, Children’s Hospital of Philadelphia

Student

Ridhi Sahani, Bucknell University