The response of the MiL-Lx leg fitted with combat boots under impact loading

Abstract

Anti-Vehicular Landmines (AVLs) or under-belly Improvised Explosive Devices (IEDs) or even a side-attack IEDs are found to be some of the major threat for military vehicles and their occupants. The lower extremities of the occupants are very prone to the injuries more especially during underbelly detonation of the AVL or IED due to their spatial proximity to the rapid deforming floor. Lower limb surrogate legs, such as a Hybrid III or Military Lower Extremity (MiL-Lx) are used to quantify the impulse loading on the lower extremity when subjected to the rapid deforming floor. Military boots could be used by the occupants to mitigate the blast loading impact on the lower extremities. This work present the response of the MiL-Lx leg fitted with two different combat boots (Meindl and Lowa) and exposed to typical blast loading conditions. The purpose of the work was to evaluate the potential load mitigation effects of the two boots using the MiL-Lx leg. The blast loading conditions were simulated using the modified lower limb impactor at several loading velocities spanning from 2.7-10.2 m/s. The MiL-Lx leg was instrumented with triaxial load cells located at the upper and lower tibia. The results shows that both combat boots attenuate the peak force only at the lower tibia while showing slight increase of the peak force at the upper tibia. Within the lower loading severities, the Meindl desert combat boot shows a better peak force attenuation than the Lowa desert combat boot at the upper tibia. Both boots shows a delay in time to peak force at both upper and lower tibia. The Meindl boot shows a longer delay in time to peak force than the Lowa desert combat boot. Both boots shows an increase in impulse determined at the upper and lower tibia and across the loading severities. The increase in impulse is attributed to the presence of the boot materials and the thicker boot showed a higher increase.