Personalization of human body models to simulate obese occupants in automotive safety

Overview & Synopsis

The prevalence of obesity have been increasing for several decades and it is now estimated to affect close to 30% of population worldwide. The increased mass of adipose tissues of obese vehicle occupants can negatively affect the risk and severity of injuries sustained during a car crash. Human Body Models (HBM) are a useful tool for studying crash scenarios in order to design better safety systems, but they mainly target non-obese population. However, morphing has been suggested as an alternative to the costly development of new model. This thesis presents enhancements to existing morphing methods which allow using very detailed morphing targets to personalize not only the external shape of the body, but also the inside. The methods were implemented as open source software in the PIPER framework. They were then applied to create a detailed personalized HBM that describe both the subcutaneous fat and abdominal fold of three obese Post Mortem Human Surrogates (PMHS). Tests performed on the same PMHS to characterize the interaction of an obese abdomen with the safety belt were then simulated using the morphed models. The results show the importance of the abdominal fold, which was not accounted for in previous studies, to correctly capture the behaviour of the abdomen. Overall, these results bring new knowledge and methods allowing to better understand and simulate the restrains conditions of obese subjects in automotive environment. These should help in the future to design more efficient restrain systems