UCSD Research May Improve Automobile Safety

RESEARCHERS AT THE JACOBS SCHOOL have developed polymer composite materials to improve automobile safety during crashes. According to Structural Engineering Professor Vistasp Karbhari, "By using composite crash rails, the energy generated during impact can be absorbed and controlled, allowing the vehicle to withstand larger accidents with less injury to occupants and less damage to the critical structural elements."

Currently, crash rails run perpendicular to the front bumper and are typically made of steel. They receive a tremendous amount of energy during impact, at which time they buckle. This energy can be transferred to the passengers. In contrast, composite rails can be designed to fail in very precise ways through a sequence of damage mechanisms, absorbing and dampening the energy. "This technology can make these cars lighter but also safer – a combination that historically has not meshed well," explains Karbhari.

Karbhari and his students (one of whom, Jonathan Haller, now works at Ford in Detroit) have been working on these designs for many years. They have received one patent and are applying for two more. A number of automotive companies are interested in the research and one is testing a concept in which a composite rail shreds from within. The shredding mechanism has been designed to absorb about twice the energy of previous composite systems and fail in a predetermined sequence. This allows for gradual impact and a tailored transition, thereby ensuring that deceleration forces do not cause injury.