Advanced Finite Element Model Development of the Q1 Anthropomorphic Test Device

Anthropomorphic test devices (ATDs), commonly referred to as dummies or manikins, are used in simulated collisions of new vehicle design as mechanical surrogates of humans to develop and standardize safer occupant protective systems. The main goal of standards in the automotive as well as in the aerospace industry, is to prevent and mitigate the risk of severe injuries and the preservation of human life. At first, crash tests were conducted using corpses or volunteers. However, the problem of finding willing volunteers as well as dead bodies free from external injuries or internal damage, led engineers to focus on developing dummies designed to replicate human characteristics. Earlier versions of dummies were strictly used for loading the vehicle dynamically, focusing only on weight and size in their construction. In contrast, human physical characteristics such as size, shape, mass, stiffness, and energy absorption and dissipation are accurately mimicked, now. That is because current ATDs are engineered to replicate the dynamic impact response of the human body in terms of trajectory, velocity, acceleration, deformation, and articulation. In addition, they are designed to be biofidelic, enabling the evaluation of injury type and severity. This is allowed due to the measurement of the impact forces, accelerations, deformations, and loading of various body parts using advanced sensors and instrumentation integrated into the dummies. The increase in computational power have facilitated the integration of computational methods alongside experimental testing. The developement of a precise and reliable finite element model (FEM) offers many opportunities in the field of crash safety: these models facilitate the optimization of both vehicle and restraint system designs and simulated test setups can be quickly modified to evaluate responses under different conditions. The goal of this thesis is to assemble an accurate Q1 FEM for CRS (Child Restraint systems) and car crash safety analysis with the support of Phitec Ingegneria srl (PHITEC). The company develops and validates virtual models of the Q-Series, a family of child dummies of various ages and sizes that also includes the Q1. This study traces the entire FEM development process, from the meshing and connection of parts, through the assemblies validation tests, up to the final verification of the integrity of the model. In particular, the results of the validation tests, in terms of accelerations, forces, moments, etc., are compared with the sensor output data obtained from the same physical tests conducted in the laboratory as prescribed by the regulations. A sufficient overlap of the curves proves the correlation between the existing manikin and its numerical model, allowing the latter to be considered complete and suitable for use in numerical crash test simulations.