Use of MADYMO’s human facet model to evaluate the risk of head injury in impact

Fréchède, Bertrand; McIntosh, Andrew

MADYMO® rigid-body models are widely used in the automotive industry for a range of occupant protection related applications. These models have been evaluated at various levels against a range of experimental conditions including blunt impacts. To date the greatest focus for head impacts has been the study of severe impacts. It appears beneficial to broaden the field of validation of these models, and to expand the knowledge of tolerance limits associated with lower severity injury. In this case, mild traumatic brain injury (MTBI).

A simulation protocol was developed using MADYMO’s human facet models to reconstruct 27 real-life concussive head impacts from impact sports. The cases were selected from a set that had been studied previously using a video analysis protocol. The contact behaviour of the model was first evaluated against both experimental and numerical results available in the literature. The video impact cases were then reconstructed and simulated, allowing for the assessment of a range of global biomechanical parameters that have been shown to be correlated with injury risk. The reliability of these reconstructions was evaluated by means of a sensitivity analysis of the influence of several independent variables on these dynamic outputs.

The results showed that the use of MADYMO’s human facet model was adequate to obtain a representative estimate of head dynamics associated with soft to medium impact severities. They also hinted at the model’s limitations to accurately model short impact durations impacts. The following mean peak values for MTBI were obtained from the reconstruction of the real-life impacts: 103 g for the head centre of gravity linear acceleration, 8022 rad/s2 for the head angular acceleration and 359 for the HIC.

These values compare well with other studies and should contribute to the identification of the level at which injury first occurs.

Year

Entry

2002

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1993

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1993

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2000

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1980