Lumbar load and dynamic response index (DRI) are two common lumbar response index used to assess passenger

lumbar injuries during emergency landing of aircraft. To elucidate the differences between these two metrics, firstly,

the seat-occupant finite element model and the occupant upper limb lumped parameter model were established in

this paper. Secondly, a comparative verification is conducted between the seat-occupant finite element model and

the occupant upper limb lumped parameter model. Finally, a parametric analysis was conducted on these two lumbar response index by changing the loading time and loading peak value. The results show that the DRI value calculated by floor acceleration is lower than that calculated by pelvic acceleration, and when the loading time is constant, the DRI value shows an increasing trend with the increase of loading peak value. When the loading peak value is constant, the DRI value shows the trend of increasing first and then decreasing with the increase of loading

time. When the speed change is constant, the DRI value shows an increasing trend with the increase of the loading

peak value. In summary, by sorting out and analyzing the principle of DRI, it is helpful to promote the continuous

improvement of the criteria for determining occupant lumbar injuries.

dynamic response index (DRI), lumped parameter model, lumbar injury