Research - Foot Impact

Gaurav Nilakantan

Research—Foot Impact

Anti tank (AT) mines pose a serious threat to the occupants of armored vehicles. High acceleration pulses and impact forces are transmitted to the occupant through vehicle-occupant contact interfaces, such as the floor and seat, posing the risk of moderate to fatal injury.

This research simulates the impact of a dummy’s feet by a rigid wall whose upward motion is comparable to the reaction of the floor of an armored vehicle to a mine blast directly underneath it. A 50^th percentile HYBRID III dummy is used to simulate the occupant. The dummy is seated in various positions to study the effect of occupant sitting position on the injury assessment. The explicit non-linear finite element software LS-DYNA is used to perform all numerical simulations.

The input pulses that control the motion of the rigid wall (acceleration, velocity or displacement control) are varied in a step wise manner to determine its effect on extent of injury. Data such as hip and knee moment, tibia axial compressive force and foot acceleration are collected from the dummy during the simulation and compared to allowable values from various references to assess injury.

By numerically simulating the impact of occupant lower leg during a mine blast under a vehicle, the significant cost of conducting live, full scale tests can be reduced.