Redesign of rear end of a car to minimise whiplash injury

Among automobile related injuries, whiplash injury is very common. Its occurrence is quite common as this can be caused even by collisions at very low speeds. It does not get as much attention as the injuries sustained during frontal collision even though these can be quite debilitating and have long term effects. In this project, with an aim to minimise the severity of whiplash injury to the occupants during rear end collisions, rear end of a car has been redesigned. Parts of rear end structure of a popular car have been redesigned to manage crash energy better during rear end collisions.

In the current project work, first a rear end collision between two models of Geo Metro, a popular automobile was simulated using explicit dynamic simulation. From the results of this simulation crash pulse, deceleration experienced by the car hit from behind, was obtained. This was used as “load’ in the multibody simulation of a sled test to assess the effect of collision on the physiology of the occupant and resulting injury levels. The simulation also provided in insight into the crash energy management of the components in the rear end. Designs of components of rear end structure for better energy management and reduced injuries to the occupants were developed and analysed. From among many designs, some designs were successful in bringing down the injury levels to the occupants within acceptable levels. This was checked for three very common types of rear end collisions-full width, 50% offset and 30º oblique conditions.