Passenger Vehicle Crash Test Procedure Developments in the Vc-compat Project

The project “Improvement of Vehicle Crash Compatibility through the development of Crash Test Procedures” (VC-Compat) is a research activity sponsored under the European Commission 5 Framework Programme. It consists of two parallel research activities, one focusing on car-to-car compatibility and the other on car-to-truck compatibility. The main objective of the car-to-car research is the development of crash test procedures to assess frontal impact crash compatibility. The carto-truck objective is to develop test methods to assess energy absorbing frontal underrun protection for trucks. The midterm project status of the car-to-car work program is reported in this paper. A survey of European passenger vehicles has been conducted to construct a database of common crashworthiness structures. A review of the detailed accident databases in Germany and UK has been used to identify a target population of accident victims that could benefit from improved vehicle compatibility. Testing and modelling activities have been conducted to improve the understanding of the relationship between crash behaviour in the candidate test procedures and car-tocar crashes. These research activities are helping to develop and evaluate candidate test procedures. To date, work has focused on the Full Width Deformable Barrier (FWDB) and Progressive Deformable Barrier (PDB) tests, which use two different approaches to assess a car’s compatibility. The FWDB test uses load cell wall force measurements whereas the PDB test uses barrier deformation measurements. The activities described herein will continue throughout the project and lead to draft test procedures with performance criteria and limits. * The car definition includes SUVs. INTRODUCTION Following the introduction of the European frontal and side impact Directives and EuroNCAP, car safety has made a major step forward. Even so, there are still over 38000 fatalities and 1.6 million injured people due to traffic accidents in Europe [1]. Passive safety equipment operates well under idealized crash test conditions. However, behaviour of car structures and safety systems during real world conditions is not always directly comparable to crash tested behaviour, especially in car-to-car crashes. The next step to further improve frontal impact protection is to improve compatibility. Crash compatibility will ensure that car frontal structures are more effectively utilized in car-to-car collisions. This should help reduce compartment intrusion in severe accidents and thereby lead to a decrease in the number of serious and fatal injuries. Compatibility is a complex issue but can be broken down into three subtopics: structural interaction, frontal force levels and compartment strength. Structural interaction is a measurement of how well vehicles interact in frontal impacts. If the structural interaction is poor, the energy absorbing front structures of the vehicle may not function as designed leading to a risk of compartment intrusion at lower than designed impact severities. In general, frontal force levels are currently related to vehicle mass[2]. As a consequence, small vehicles absorb more than their share of the impact energy as they are unable to deform the heavier vehicle at the higher force levels required. Matched frontal force levels would ensure that both vehicles in an impact absorb their share of the kinetic energy. This would reduce the risk of injury for the occupant in the lighter vehicle. Compartment strength is closely related to frontal force levels but is nevertheless distinguished since it is such an important issue for self-protection. In cases where the vehicle front structures do not absorb the amount of energy as designed or in cases where the vehicle is exposed to higher impact severity than it is designed for the compartment strength needs to be sufficiently high to resist a compartment collapse. VC-Compat[3] is a 3-year project, part financed by the European Commission which started in March 1 2003 and is split into two research legs; a car-to-car † EuroNCAP is the European New Car Assessment Programme which provides the consumer with car safety ratings