Principal Investigator: Aditya Belwadi, PhD, Children’s Hospital of Philadelphia

WHAT WAS THE PURPOSE OF THIS PROJECT?

Families have choices in booster seats, which differ in design and belt routing. We aimed to examine how these different designs – including more portable booster seat designs – affect restraint capabilities in a crash.

In Year 1 of the project, we used an instrumented Q6 ATD to test various booster seat designs in a variety of laboratory test conditions. We observed important differences in the kinematic performance of these seats. This year, we focused on how test setup affected the results. We used computational models to look at how the results changed with two test changes that better reflect the real world: (1) vehicle seat versus test bench (including adding retractors/pretensioners to the belt) and (2) presence of a side curtain air bag.

WHAT DID YOU FIND OUT IN YEAR 2?

We continued to see differences in kinematics with the different booster seat designs, but we also found that the testing platform (bench versus vehicle seat) played an important role in the response of the occupant. For frontal tests, the addition of a retractor/pretensioner in the vehicle seat setup improved the interaction of the lap belt with the pelvis but reduced some of the unusual kinematics we observed with some newer booster seat designs in the Year 1 testing. For side impacts, the side curtain air bag showed encouraging benefits that deserve further study to quantify the nuances of the interaction of booster seats and the vehicle.

WHAT WILL YOU DO WITH THESE FINDINGS?

At the core of safety evaluation is how the specific test methodology mimics the real world. From the current study we identified the importance of testing on vehicle seats in part driven by the addition of a retractor/pretensioner. I hope these findings fuel new research in booster seat testing that better reflects real world vehicles.

Students

Nhat Duong, Drexel University; Jalaj Maheshwari, University of Pennsylvania; Shreyas Sarfare, University of Pennsylvania

IAB Mentors

Keith Nagelski, Britax Child Safety, Inc.; Emily Thomas, Consumer Reports; Mark LaPlante, Graco Children’s Products Inc.; Jerry Wang, Humanetics Innovative Solutions Inc.; Hiromasa Tanji, TK Holdings Inc.; Schuyler St. Lawrence, Toyota USA; Julie Kleinert, Emeritus Chair; Uwe Meissner, Technical Advisor