Universidad de Zaragoza. Zaragoza (Spain)
May 18th, 2024
Summary:
The aim of this dissertation is to evaluate how Human Body Models (HBM) can be improved to accurately predict the chest deflection in oblique impact configurations and how the different personalization techniques influence the prediction. HBM, which can be modified to individual characteristics, are instrumental in study of the biomechanics. Accurately measuring chest deflection is crucial for evaluating thoracic biomechanics and injury risk. Therefore, this study aims to compare HBM predictions of chest deformation with real-world data to better understand how subject-specific factors impact chest motion and, consequently, safety systems.
To achieve these goals, the study conducted three sled tests in a nearside oblique impact scenario at the University of Zaragoza's Impact Laboratory. It used the SAFER HBM v8 model based on the THUMS v3 model as a reference point for assessing personalization techniques. Various versions of the model were employed, including the unmodified base model, and modified models with aligned spine curvature, mass and anthropometry adjustments to mimic individual post-mortem human subjects (PMHS). The research used the CORA rating to quantify the correlation between predicted responses and sled test results.
The subsequent chapters built upon these findings, each with a specific focus. Chapter 3 quantified the impact of personalization techniques on spinal kinematics during oblique impacts. The study compared predicted displacements from HBM simulations with actual spinal displacements recorded during physical tests. It identified factors contributing to disparities between predictions and measurements, including modelling limitations or age-related variations in body composition among others.
Chapter 4 centred on analysing the six degrees of freedom (6DOF) motion of the human spine during crash events. The study explored how personalization techniques influenced predictions of spinal bone rotations using HBM. The Finite Helical Axis (FHA) was used to model dynamic motion, with a focus on precision in motion descriptions. The study compared results from various HBM versions assessing their significance with statistical tests.
In Chapter 5, the research conducted an evaluation of chest deformation prediction capability of the models. It assessed how personalization techniques influenced the prediction. The study presents a sensitivity analysis of the chest deflection of the HBM in relation to the personalization techniques.
In summary, this dissertation's primary objective is to enhance the understanding in biomechanical responses during oblique automotive impacts, particularly in the thoracic and spinal regions. These oblique impacts are known to cause more significant chest deformations, making them crucial for injury prevention and safety standards. The research quantitatively assesses the influence of personalization techniques on spinal kinematics and chest deformation using HBM. It contributes to the understanding of these biomechanical responses and identifies areas for refinement in predictive modelling to enhance automotive safety.
Spanish layman's summary:
Este estudio investiga los Modelos del Cuerpo Humano (HBM) para predecir la deflexión torácica en impactos oblicuos. Mediante pruebas y técnicas de personalización, evalúa la precisión de los HBM en representar la biomecánica humana, buscando mejorar la seguridad al entender mejor las respuestas torácicas y espinales.
English layman's summary:
This study investigates Human Body Models (HBM) to predict chest deflection in oblique impacts. Using sled tests and personalization techniques, it evaluates HBM accuracy in representing human biomecçhanics, aiming to enhance safety systems by better understanding thoracic and spinal responses.
Descriptors: Bio-mechanics, Simulation
Citation:
A. Piqueras (2024), Comparative analysis of Human Body Model and post mortem human subjects in oblique impact: evaluating chest deformation and personalization techniques. Universidad de Zaragoza. Zaragoza (Spain).
