Manufacturing
Martec was contracted by a large
Canadian manufacturer of automobile accessories to
assist with the structural design of one of their
new product lines. This manufacturer produces accessories
that are supplied as original equipment with new automobiles.
One accessory that they manufacture is a bullbar for
sport utility vehicles (SUVs). Bullbars are tubular
structures that protect the front grills of SUVs in
minor impacts.
Recently, legislation has been introduced in Europe to protect pedestrians during frontal impact with vehicles. This has resulted in the European Experimental Vehicle Committee (EEVC) designing impact test requirements to be passed for all bullbars to be marketed and sold in Europe. The test requirements are very demanding and are based upon reducing the level of deceleration of critical pedestrian body components to a level where an impact with a vehicle at 40 km/h can be survived.
In order to reduce prototyping costs and time-to-market
to a competitive level, virtual prototyping was utilized
by Martec to assess current designs and to redesign
bullbar components. Martec used the special purpose
impact analysis program PamCrash to simulate the impact
tests and to ensure that the proposed designs would
pass the test requirements of the EEVC. Martec performed
compression tests on candidate materials to obtain
material response data required for the impact analysis.
Load displacement curves were obtained at various
rates in order to assess material response under dynamic
loading conditions. Tubular sections were designed
with various types of energy absorbing foams encased
in plastic shells. A design was derived that was capable
of passing the EEVC requirements.
|
