CURRENT FRONT STIFFNESS OF EUROPEAN VEHICLES WITH REGARD TO COMPATIBILITY 2001-06-0043

EuroNCAP tests are carried out since 1997. The test procedure in general is comparible to the EC Directive 96/79 with a test speed of 64 km/h. This increased test speed implies a higher frontal stiffness for new vehicle designs in order to achieve a high ranking. This frontal stiffness is one of the major factors for compatibility in car to car collisions.

To support the European 4th framework compatibility research activity, load cell barriers are used in ENCAP tests carried out at the TNO Crash Safety Centre and TRL.

In this paper global force displacement characteristics of a number of different vehicle classes are compared and analysed. It will be made clear that small vehicles in the past known not to be strong can produce comparable force levels as large cars. For compatibility this means that in small car against large car collisions the small car’s passenger compartment can stay stable and can offer better protection to the occupants, since from accident analyses it is known that serious injury often is caused by high intrusion into the passenger compartment.

For frontal impacts this means that ENCAP tests have driven small cars to increased compatibility for one aspect of compatibility (cabin integrety) at higher speed.

MPV’s with high masses and little crushable space show more aggressive force displacement characteristics. This car category is expected to behave less compatible hitting small cars or medium size passenger cars. A longer crushable space for this category is desired, which is in conflict with the special look for these vehicles.

This trend in stiffer vehicle fronts might result in future modifications of the European side impact barrier, which is currently based on average vehicle fronts of old vehicles. This item is only mentioned and will not be further discussed.