Simulation analysis for the safety protection of cervical vertebra under unusual landing impact

The objective of this study was to analyse and evaluate the protection function and feasibility of two types of human neck safety equipment under unusual landings. Human head and neck dynamic responses were simulated by constructing a mechanical model of the human-seat system, which was equipped with two kinds of head support systems. The force and moment in the human neck were calculated. The protection function of the head support systems was evaluated according to the injury criteria HIC (head injury criterion) and N_ij (neck injury criterion). Two kinds of safety equipment were used under unusual landing. The results of the experiment showed that N_ij is smaller than the injury criterion limits under normal landings, and that the safety equipment provided effective protection. The safety equipment was confirmed to reduce the degree of neck injuries resulting from unusual landing impacts.