Biomechanical investigation of astronaut's seat geometry to reduce neck and head injuries while landing impact

摘要

The present study aims at designing a seat position to preserve the safety of occupants under acceleration and impact loads of landing conditions. So, using astronaut multi-body dynamics, initially, the astronaut's dynamic response to sustained loads while landing impact is at work was determined. Next, by applying the sustained loads to the three-dimensional finite element model of the head, the dynamic response of the head to sustained loads was determined. Subsequently, the probability of occupants' being injured was assessed by changing the seat angles and using the neck-injury index and the head-tissue injury criteria. Furthermore, sensitivity analysis was carried out in order to evaluate the sensitivity of injuries to changed seat angles. Results indicate that changing the trunk angles leads to changes up to 12% and 108% in the probability of injuries to the head and neck, respectively. Moreover, changing the angles of head and neck leads to changes up to 10% and 192% in the probability of injuries to the head and neck, respectively. Results also indicate that the probability of injuries to the head and neck can be reduced up to 0.17 and 0.23, respectively, if the astronaut is seated in an optimal landing position.