Recent research on behind-armor blunt trauma (BABT) has focused on the personal protection offered by lightweight armor. A finite element analysis was performed to improve the biofidelity of the US Army Research Laboratory (ARL) human torso model to prepare for simulating blunt chest impacts and BABT. The overly stiff linear elastic material models for the torso were replaced with material characterizations drawn from current literature. FE torso biofidelity was determined by comparing peak force, force-compression, peak compression, and energy absorption data with cadaver responses to a 23.5 kg pendulum impacting at the sternum at 6.7 m/s. Nonlinear foam, viscous foam, soft rubbers, fibrous hyperelastic rubbers, and low moduli elastic material were considered as material models for the flesh, organs, and bones. Simulations modifying one tissue type revealed that the flesh characterization was most crucial for predicting compression and force, followed closely by the organs characterizations. Combining multiple tissue modifications allowed the FE torso to mimic the cadaveric torsos by reducing peak force and increasing chest compression and energy absorption. Limitations imposed by the Lagrangian finite element approach are discussed with potential workarounds described. Proposed future work is split between considering additional impact scenarios accounting for position and biomaterial variability.
Solving the magnetocardiography forward problem in a realistic three-dimensional heart-torso model
