An offset rigid barrier-based test: equivalence to the Insurance Institute for Highway Safety frontal offset impact safety test

Abstract

The current Insurance Institute for Highway Safety (IIHS) frontal offset impact safety assessment, which is similar to the European New Car Assessment Program (EuroNCAP), uses a fixed deformable barrier of aluminium honeycomb construction. The IIHS offset deformable barrier (ODB), designed to mimic an average collision partner during an accident, is however a relatively expensive and time-consuming representation for evaluating the safety of a given vehicle during frontal collisions. The repeatability of tests based on ODBs has also been questioned in some investigations reported in published literature. In the current paper, available finite element models of a compact car (Dodge Neon) and a full-size car (Dodge Intrepid) were first improved and validated against actual test results reported by the IIHS. Each of these validated models was next subjected to 40% offset impact against a rigid wall in lieu of the deformable IIHS barrier at a lower speed calculated on the basis of energy balance. The simulations were carried out with the aid of the explicit code LS-DYNA. It was shown that a remarkably good correlation can be obtained for occupant compartment intrusions for impact against an offset rigid barrier vis-à-vis the IIHS ODB. Thus, at a lower speed the offset rigid barrier can be a cost-effective and efficient alternative to the currently used ODB.