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Design Development of Energy Absorbing Ribs for Meeting FMVSS 201 Extended Head Impact
ISSN: 0148-7191, e-ISSN: 2688-3627
Published February 24, 1997 by SAE International in United States
Annotation ability available
Revisions to the FMVSS 201 head impact legislation have had a significant impact on the design and engineering of upper interior trim components of cars and light trucks. Structural performance with energy absorbing capability to prevent head injury is now a significant addition to these requirements. However, occupant visibility blockage limits the amount of packaging space available for implementing countermeasures in this area.
A novel approach to meeting the FMVSS 201 structural requirements, while keeping the interior trim on the vehicle minimally changed, has been developed. This approach requires the use of energy absorbing rib structures sandwiched between the trim panel and the inner body-in-white (B/W) sheet metal in A and B pillars. Heat staking is used to attach the rib structure to the interior trim panel. This design approach provides flexibility, particularly so for vehicle platforms that will be manufactured and sold in markets where no provision for head impact protection is required. In such cases, the same trim panel design can be used with no modifications, and the rib cartridge can be selectively included in those vehicles to be sold in North America.
Finite element (FE) models of all surrounding B/W structures were built to simulate the compliance of the entire system. Non-linear FE analysis was extensively used to develop the optimum design of the rib cartridge structure. High speed, true-stress/true-strain data were generated for the different materials used to obtain a fair degree of accuracy and correlation between the analytical simulation and testing. The FE analysis results indicate the rib cartridge system is able to meet the FMVSS 201 requirements.
CitationGandhe, G., Lorenzo, L., and Noritake, Y., "Design Development of Energy Absorbing Ribs for Meeting FMVSS 201 Extended Head Impact," SAE Technical Paper 970161, 1997, https://doi.org/10.4271/970161.
- Standard No. 201: Head Impact Protection: Final Rule, 49 CFR, Parts 571, 572 and 589 [Docket No. 92-98; Notice 4], RIN 2127-AB85, Federal Motor Vehicle Safety Standards, National Highway Traffic Safety Administration, Department of Transportation, 1995.
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- Laboratory Test Procedure for FMVSS 201: Occupant Protection in Interior Impact, Upper Interior Head Impact Protection, National Highway Traffic Safety Administration, Department of Transportation.
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