A mathematical human body model for frontal and rearward seated automotive impact loading

Mathematical modelling is widely used for crash-safety research and design. However, most occupant models used in crash simulations are based on crash dummies and thereby inherit their apparent limitations. Several models simulating parts of the real human body have been published, but only few describe the entire human body and these models were developed and validated only for a limited range of conditions. This paper describes a human body model for both frontal and rearward loading. A combination of modelling techniques is applied using rigid bodies for most body segments, but describing the thorax as a flexible structure. The skin is described in detail using an arbitrary surface. Static and dynamic properties of the articulations have been derived from literature. The RAMSIS anthropometric database has been used to define a model representing a 50th percentile male. The model has been validated using volunteer tests performed at NBDL ranging from 3-15 G severity, and using established dummy biofidelity requirements for blunt thoracic impact. A satisfactory prediction has been obtained for chest deflections, head kinematics and accelerations and for kinematics and accelerations at the upper thoracic vertebra. Recommendations are given for further development and validation of the model, and for validation of models of different body sizes.