Development of restraint systems with considerations for equality of injury risk

Ridella, Stephen A.; McCann, Matthew J.; Turnbull, Roy C.; Bayley, Gregory S.

Occupant restraint system development continues to evolve as new regulations and consumer demand drive more complex solutions. Traditional seat belt and airbag designs are giving way to more intelligent systems that respond to crash and occupant conditions. In regulated vehicle compliance safety tests, occupant performance is usually judged against injury criteria that differ with respect to occupant size. While for a given test, two different occupant sizes may give results that pass the criteria, their probabilities of injury for a given body region may not be equal. It may be possible to change restraint configurations that not only demonstrate compliance to recognized injury criteria for a given occupant, but additionally demonstrate that for a given crash mode, an equal probability of injury exists for all body regions of a range of adult occupant sizes. This paper will discuss a computer modeling approach devised to analyze a particular vehicle environment and range of occupant sizes. A design of experiments was carried out that adjusted parameters of the restraint system including seat belt pretensioners, load limits, and various airbag components. For each analysis, the probability of injury by body region and occupant were compared to find the set of components that comprise a system to give equal probability of injury for each body region for each occupant. Results of the design of experiments, statistical analysis and impact on restraint system development will be discussed. This paper documents a new approach to restraint system development as it looks beyond specific injury criteria to injury risk comparisons.

Year

Entry

2003

Kent R, Patrie J, Poteau F, Matsuoka F, Mullen C. Development of an age-dependent thoracic injury criterion for frontal. In: Proceedings of the 18th International Technical Conference on the Enhanced Safety of Vehicles (ESV). May 19-22, 2003; Nagoya, Japan.

2001

Cuerden R, Hill J, Kirk A, Mackay M. The potential effectiveness of adaptive restraints. In: Proceedings of the 2001 International IRCOBI Conference on the Biomechanics of Impact. October 10-12, 2001; Isle of Man, UK.

1998

Foret-Bruno J-Y, Trosseille X, Le Coz J-Y, Bendjellal F, Steyer C, Phalempin T, Villeforceix D, Dandres P, Got C. Thoracic injury risk in frontal car crashes with occupant restrained with belt load limiter. In: Proceedings of the 42nd Stapp Car Crash Conference. November 2-4, 1998; Tempa, AZ. Warrendale, PA: Society of Automotive Engineers:331-352. SAE 983166.

1999

Eppinger R, Sun E, Bandak F, Haffner M, Khaewpong N, Maltese M, Kuppa S, Nguyen T, Takhounts E, Tannous R, Zhang A, Saul R. Development of Improved Injury Criteria for the Assessment of Advanced Automotive Restraint Systems - II. Washington, DC: National Highway Traffic Safety Administration (NHTSA); November 1999.

1998

Happee R, van Haaster R, Michaelsen L, Hoffmann R. Optimisation of vehicle passive safety for occupants with varying anthropometry. In: Proceedings of the 16th International Technical Conference on the Enhanced Safety of Vehicles (ESV). May 31–June 4, 1998; Windsor, Ontario, Canada.1919-1924.