ACCELERATION PULSES AND CRASH SEVERITY IN LOW VELOCITY REAR IMPACTS – REAL WORLD DATA AND BARRIER TESTS

Dummy responses in a crash test can vary depending not only on the change of velocity but also on how the impact was generated. Literature reporting how acceleration pulses can vary in cars impacted in different configurations is limited. The aim of this study was to collect and categorise different acceleration pulses in 3 different types of rear collision. The acceleration pulse resulting from a solid, 1000 kg, mobile barrier test at 40% overlap and an impact velocity of 15 km/h was studied for 33 different cars. Seven cars were impacted at 100% overlap at higher impact velocities using the same mobile barrier. Acceleration pulses from two different car types in real-world collisions producing a similar change of velocity were also analysed.

The results from the barrier tests show that a similar change of velocity can be generated by a large variety of pulse shapes in low velocity rear impacts. The results from real-world collisions showed that a similar change of velocity was generated in different ways both in terms of peak and mean acceleration. The results of this study highlight the importance of knowing the acceleration pulse both when evaluating the severity of a real world crash and when designing test methods for evaluating vehicle safety performance in low velocity rear-end impacts, particularly in respect of soft tissue neck injuries.