Feasibility study of an adaptive energy absorbing system for passenger vehicles

Many car front crashes happen with an offset between the car and the obstacle (or the second car). In this case, present design of car front crash zone is made as a compromise reconciling requirements of frontal crash tests with and without offset. Using the principle of pyrotechnic detachable connectors, a control of car deceleration is possible. System controller recognizing initial pre-crash parameters (velocity, mass, stiffness and overlap) can choose several levels of dissipated energy for each absorber. Three methodologies with different levels of simplification have been chosen to calculate absorbed energy and levels of deceleration. A simplified analytical, numerical Lumped Mass – Spring (LMS) model and numerical FE explicit models of car front structures were created. Two crash scenarios were analyzed: full front crash and 50% offset crash for two cases: with an unmodified vehicle and when the absorbing structure was equipped in adaptive system. The objective of the system was to get similar levels of absorbed energy and crushing distance in both impact cases. A feasibility study of adaptive energy absorbing system has been performed based on comparison of crash analysis results.