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The objectives of this study are to generate validation data for human models intended for simulation of occupant kinematics in a pre-crash phase, and to evaluate the effect of an integrated safety system on driver kinematics and muscle responses. Eleven male and nine female volunteers, driving a passenger car on ordinary roads, performed maximum voluntary braking; they were also subjected to autonomous braking events with both standard and reversible pre-tensioned restraints. Kinematic data was acquired through film analysis, and surface electromyography (EMG) was recorded bilaterally for muscles in the neck, the upper extremities, and lumbar region. Maximum voluntary contractions (MVCs) were carried out in a driving posture for normalization of the EMG. Seat belt positions, interaction forces, and seat indentions were measured. During normal driving, all muscle activity was below 5% of MVC for females and 9% for males.

A Finite Element (FE) model of isolated head and neck complex was developed aiming to investigate the mechanisms of injury from axial impacts, in the sagittal plane, and the injury thresholds from experimental studies reported in the literature. The model was validated on a local and a global level, showing a significant correlation with experimental investigations and thereby having the potential to predict both reported injuries and dynamic buckling modes. The frequently reported Hangmans'' fracture was predicted to occur at an axial load of about 3.5 kN and at a local injury threshold of 191 MPa in the compact bone of C2. Also, when analyzing an experimentally designed inner roof of a vehicle, the FE model showed that an induced anterior translation of the head reduced both stress and forces of the cervical spine bone. Moreover, the recent FE model suggests that combined compression/flexion may result in less severe injuries compared to pure compression or compression extension.