SBIR-STTR Award

Corvid Technologies, LLC (Corvid) and the University of Virginia Center for Applied Biomechanics (UVA-CAB) propose to develop finite element models of mounted warfighters to evaluate injury risk in underbody blast (UBB) loading events and utilize these models to improve the performance of energy-attenuating (EA) seat safety. The proposed approach will utilize a high-fidelity computational physics-based method to model the human body and EA seat using techniques previously established and employed for UBB crew injury analysis. Corvid is uniquely positioned to efficiently accomplish the objectives of this topic due to its previous involvement with human body model development, years of experience in modeling and simulation of vehicle blast events, and its in-house, high performance computing (HPC) resources and software development capabilities. Partnership with UVA-CAB will provide valuable insight into pelvis, lumbar spine, and femur injury risk though their extensive cadaveric testing background in both the UBB and automotive loading environments.

Benefit:
Corvid and UVA-CAB will leverage experience in the modeling of military vehicle systems, assessment of human injury, and simulation-based design and optimization to demonstrate EA seat design improvement is possible when taking into account postural and anthropomorphic effects on occupant injury. The detailed modeling approach, and its specific implementation by the Corvid-UVA team, will provide a new and innovative solution to improve upon the injury assessment tools for the articulated 50th percentile male CAVEMAN model. Enhancing the injury understanding and modeling capability of mounted warfighters due to postural and anthropomorphic effects will allow for new, innovative EA system designs specifically optimized based on human injury risk to skeletal and soft tissues in the pelvis, lumbar spine, and femur.

Keywords:
skeletal and soft tissue, skeletal and soft tissue, combat vehicle, seat safety, injury, biomechanics, underbody blast

Corvid and the University of Virginia Center for Applied Biomechanics propose to continue the development of the CAVEMAN model as a tool to improve injury assessment capabilities for warfighters exposed to underbody blast loading events. To ensure proper performance of energy-attenuating (EA) seat safety for warfighters, these systems must be designed to function across the range of anthropometry and seated postures observed in the military. During the Phase I effort, enhancement of the CAVEMAN model proved capable of predicting differences in pelvis injury trends resulting from changes in seated posture, aligning with measured cadaveric test data. Phase II will continue to focus on the characterization and modeling of seated posture influence with an increased focus on lumbar spine injury risk as well as anthropometry induced injury changes. Development of a tool capable of warfighter injury risk prediction across anthropometric and seated posture variation is dependent on underlying injury biomechanics data sets which quantify the onset and severity of cadaveric injury in these configurations. The effect of the seated posture influence on lumbar spine injuries for UBB loading has yet to be evaluated. Thus, the Phase II effort will begin by expanding the component level pelvis testing protocols at UVA to include larger sections of the cadaveric spine to investigate and quantify changes in spinal injury risk as a function of seated posture. Additionally, the influence of anthropometry on injury will also be analyzed from past cadaveric experimentation. As cadaveric specimen availability allows, the updated UVA test protocol will be used to begin experimental testing of specimens outside of the standard 50th percentile anthropometry definition. Correlation of the CAVEMAN model response to these new datasets will ensure the final injury prediction tool is capable of highlighting changes in injury risk as a function of seated posture and anthropometry throughout the human body. The CAVEMAN model will be utilized to evaluate and optimize an example military EA seat design to ensure the best protection across the entire military population. Finally, a protype of the updated EA mechanism will be fabricated and tested at UVA to demonstrate the improvements to warfighter survivability achieved through use of the CAVEMAN model in the EA seat design process.

Benefit:
At the completion of the STTR program, the CAVEMAN model will provide the government with the capability to progress beyond a single 50th percentile male anthropomorphic test device (ATD) based safety evaluation and to investigate occupant injury risk for a range of Warfighter anthropometries and seated postures. The CAVEMAN model will supply detailed injury risk information relating to the location and severity of skeletal fractures in the pelvis, lumbar spine, and femur in addition to soft tissue injury risk. This information can be used to optimize energy-attenuating seat design to ensure maximum protection for all Warfighters in vehicle blast events.

Keywords:
Human Body Model, underbody blast, CAVEMAN, Injury Biomechanics