Efforts to improve the safety of a driver of a racecar that is involved in a crash have been ongoing for a number of years. The Wayne State University Bioengineering Center has examined issues related to motorsports injury for over a decade. The Center has tested polypropylene tubes, automotive tires, foam and other non-rigid materials configured in various patterns as energy absorbing barriers. Presently, the Bioengineering Center is participating in development of the SAFER (Steel And Foam Energy Reducing) barrier for racetrack outer walls by providing biomechanical analysis of crash dummy data from crash tests conducted by the University of Nebraska–Lincoln Midwest Roadside Safety Facility. Associated with this effort is the examination of head and neck restraints such as the HANS (Head And Neck Support) device, seats with integrated headrests, and head net arrangements.
Due to the high speeds attained during racing and the highly restrained nature of the driver, racecar drivers are at particular risk to an injury known as basilar skull fracture. The risk of basilar skull fracture is increased as the neck axial tension force approaches 4100 N. This makes the axial tension load in the neck a critical measurement of safety device performance. The performance of head and neck restraints in crash sled tests using a Hybrid III 50th percentile dummy and a NASCAR style buck subjected to a 50 g crash pulse over a duration of 60 msec was evaluated. It was found that a driver not fitted with a head and neck restraint could experience a neck axial tension of 4900 N. However, it was shown that with a HANS device the neck axial forces were kept below 1500 N. Furthermore, tests using actual racecars that were pulled into barriers showed that the HANS along with other technologies provided a level of safety that previously was unavailable. By keeping HIC below 700 and the neck tension below 4100N, the HANS device along with the SAFER barrier, and a proper head rest with a well positioned head net, have been shown to be effective in racecar crash tests at 150 mph and an angle of 20 degrees.
This paper provides an overview of some of the more significant motorsports activities in which the Bioengineering Center is involved. Testing conducted during the development of the SAFER barrier is described. Included is a discussion of head and neck restraint system evaluation efforts.