At the Munich meeting NHTSA/VRTC gave an update on its correlation study on BioRID injury criteria measures to PMHS injury (WCWID-2-06).
The BioRID seems adequately repeatable and reproducible based on Gen-X tests and production seat sled tests. However, the BioRID appears to exhibit poor biofidelity in flexion so that there is only a poor correlation between BioRID measures and PMHS flexion injuries. One reason is that the BioRID was initially designed and tuned to match extension kinematics (of volunteers).
This does not mean that the BioRID is not a suitable tool for advancing safety in rear impact. The use of seat performance criteria (e.g. EuroNCAP/JNCAP/IIHS) may be capable of
reducing whiplash injuries even though the criteria may not be directly linked to the injury mechanism.
NHTSA/VRTC is proposing a design change at the BioRID to perform more biofidelic with regard to flexion. The range of motion of BioRID cervical vertebrae in flexion shall be
expanded. This would take a while and sled tests with the modified BioRID would need to be re-conducted and in a longer term more PMHS tests would be needed to strengthen correlations. This work would take a much longer time than the schedule agreed by WP.29.
So an alternative way shall be explored.