Advanced Force-Limiting Seat Belts for Occupant Crash Protection

One of the unintended consequences of seat belts in a crash are rib fractures from the belt loading. Rib fractures are most common for occupants with fragile skeletons, e.g., the elderly or women with osteoporosis. To combat this injury risk, some newer model cars are now being equipped with force-limiting seat belts – a very clever enhancement to standard seat belts which caps the force transmitted to the thorax in a crash. Force-limiting belts have the a number of drawbacks however: 1) they can only deploy once, and are hence ineffective in a multiple impact crash, (2) They also take a one-size-fits-all approach to crash protection. A 70-year old female driver with osteoporosis may require a much softer force-limiter than an 18-year old male with a stronger rib cage.

Hybrid-II Dummy with Advanced Belt System		Rib Fractures frequently follow line of belt loading

Our Objectives

1. Effectiveness. These systems have been heavily tested in the lab. Little is known however how well these systems reduce injuries in the real-world. This project will reconstruct real world crashes with cars with advanced systems to determine how will load-limiting belts are reducing injuries. Are there any unintended side effects?
2. Redeployable Load-Limiters. This project will design, build, and test an advanced force-limiting seat belt system which can redeploy after each impact in a multi-impact crash.
3. Adaptive Seat Belts. This project will design, build, and test an advanced force-limiting seat belt system which can 'adapt' to the occupant, i.e. lower loads for more frail drivers, and stronger loads for more robust drivers.