Finite Element Modeling of Passenger-side small overlap crash test with a view to correlate the right foot kinematics and injury of the Hybrid-III dummy.
2022-01-1043
03/29/2022
- Content
- In 2018, IIHS has added passenger-side(P-S) small overlap (SOI) test to the Top Safety Pick Plus(TSP+) ratings requirement, in addition to the existing driver-side (D-S) SOI test. Both the test protocols mandate the reduction of lower extremity injuries in addition to all the other overall injuries for Hybrid-III dummy. The safety of the passenger’s outboard right foot in a P-S SOI test is of more concern compared to the driver’s outboard left foot in the D-S SOI test. This is because, while the driver’s left foot rests on the foot rest, which is stiff and has sufficient offset from the toe pan to absorb the energy coming from the impact of the SOI barrier, the passenger’s right foot is positioned just above the carpet on the toe pan, and is closer to the barrier during an impact event. So it requires some countermeasures to reduce the lower extremity injuries of a passenger in P-S SOI tests. This paper describes a time efficient method to model the P-S SOI test using finite element modeling. The main objective of the study was to capture the kinematics of the right foot, its interaction with carpet and the other floor components and accurately correlate the lower tibia axial force with the test. Hence it was necessary to account for the dynamics of the complete Hybrid-III dummy model restrained by all the airbags and the seat belt system in the SOI mode. Finite element models of the Hybrid-III dummy, passenger airbag, knee airbag, seat belt system and other critical vehicle components and assemblies were modeled and incorporated. A detailed finite element model of the carpet assembly was also modeled, with different foam materials defined for its different layers. Since such detailed full car model with occupant and restraints models was computationally expensive, efforts were taken to create an efficient sled model for SOI mode using the full car structure model. The overall results of the sled model were compared with an internal SOI test. Both the kinematics and the loading of the lower tibia showed a good correlation, with a 60% reduction in simulation time. The study demonstrated that the method is effective and time efficient to understand the force on the lower extremity of the passenger dummy for a given intrusion rate of the toe pan.
- Citation
- Parab, M., Stahmer, E., and Mohammed, A., "Finite Element Modeling of Passenger-side small overlap crash test with a view to correlate the right foot kinematics and injury of the Hybrid-III dummy.," SAE Technical Paper 2022-01-1043, 2022, .