Human Body Model and Passive Safety of Vehicles: Study of Injuries on Thoracoabdominal Organs

Traumatic injuries in accidents are measured using the Abbreviated Injury Scale (AIS), a risk to life scale. This project aims to study the injuries suffered by thoraco-abdominal organs during a crash and evaluate the subsequent AIS levels. Several injury mechanisms and criteria have been studied for the thoracic organs and strain-based metrics used for the evaluation of injuries. In the case of abdominal organs, a novel approach has been used in the creation of an Organ Trauma Model (OTM) based on Peak Virtual Power (PVP) method, an energy-based indicator, as it has a linear relationship with AIS. To validate the results, a real-life accident of a vehicle impacting against street furniture was simulated using a FEM software package, replicating the accident kinematics. An acceleration trace produced from this simulation was then applied to a virtual sled model with a positioned HBM occupant. From the results, strain-based metrics were used for injury prediction of the lungs as they were not assigned any AIS levels in the accident injury report; and virtual power was calculated for the organs to which AIS levels were assigned i.e., liver and spleen. Using strain thresholds, curves representing AIS 4 injury were then produced and scaled further to create a full set of AIS corridors. PVP values were extracted from the simulation performed at case impact velocity to produce AIS levels which were compared against the reported injury levels. Comparisons resulted in the matching of AIS levels for the liver and spleen along with valid evaluations of the lung injuries presented in the report.